SINUMERIK 840D sl. Service - Functions. Manual (2018-2020)

Synchronous spindle

13.1 Brief description

When the coupling is switched on, the signals "Coarse synchronism" and "Fine synchronism" are

updated when setpoint synchronism is reached.

The size of the tolerance windows is set with machine data of the FS. Reaching of the

synchronism is influenced by the following factors:

• AV, DV: Position variance between FS and LS

• VV: Difference in speed between FS and LS

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Figure 13-3

Synchronism monitoring with COUPON and synchronism test mark WAITC with synchronization on a turning

leading spindle

Threshold values

The relevant position or velocity tolerance range for the following spindle in relation to the

leading spindle must be specified in degrees or 1 rev/min.

• Threshold value for "Coarse synchronism"

axis spec. MD37200: AV, DV: COUPLE_POS_TOL_COARSE

MD37220: VV: COUPLE_VELO_TOL_COARSE

• Threshold value for "Fine synchronism"

axis spec. MD37210: AV,DV: COUPLE_POS_TOL_FINE

MD37230: VV: COUPLE_VELO_TOL_FINE

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13.2 Programming

Speed/acceleration limits

In synchronous mode, the speed and acceleration limit values of the leading spindle are

adjusted internally in the control in such a way that the following spindle can imitate its

movement, allowing for the currently selected gear stage and effective speed ratio, without

violating its own limit values.

For example, the LS is automatically decelerated to prevent the FS from exceeding the maximum

speed in order to maintain synchronism between the spindles.

13.1.8

Dynamic offsets for synchronous spindles

ACCLIMA / ACC acceleration compensation

ACCLIMA acts with following spindles (1% to 200%).

ACCLIMA acts on the total motion of the spindle during spindle operation, i.e. also in the

uncoupled case.

VELOLIMA velocity correction

VELOLIMA (1% to 200%) acts with following spindles, limited to 100% for synchronous spindles.

VELOLIMA is cut off at 100% during spindle operation and acts on the total motion of the spindle,

i.e. also in the uncoupled case.

There is no programming of VELOLIMA for basic motion. This can be programmed using the

VELOLIM command.

Validity (part program, synchronized actions, etc.)

The dynamic offset values ACCLIMA, VELOLIMA, JERKLIMA can be programmed in the part

program or synchronized

actions. The last programming takes effect, regardless of whether it was carried out in the part

program or synchronized actions.

13.2

Programming

Coupling commands with leading-spindle programming

Command

Function

COUPDEF(FS, LS, ...)

Define coupling or change for configured coupling

COUPON(FS, LS, POSFS)

Switch the coupling on

COUPONC(FS, LS)

Activate coupling with transfer of the currently effective

speed of the following spindle

COUPOF(FS, LS, POSFS, POSLS)

Switch the coupling off

COUPOFS(FS, LS, POSFS)

Deactivate coupling with stop of the following spindle

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13.2 Programming

Command

Function

COUPDEL (FS, LS)

Delete coupling

COUPRES (FS, LS)

Reactivate configured coupling data

Coupling commands without leading-spindle programming

Command

Function

COUPOF(FS, POSFS, POSLS)

Switch the coupling off

COUPOFS(FS, POSFS)

Deactivate coupling with stop of the following spindle

COUPDEL(FS)

Delete coupling

COUPRES(FS)

Reactivate configured coupling data

See also

Spindles (Page 377)

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13.4 Special features

13.4.2

Restore synchronism of following spindle

Causes for a positional offset

When the coupling is reactivated after the drive enable signals have been canceled, a positional

offset can occur between the leading and following spindles if follow-up mode is activated. A

positional offset can be caused by:

• A part has been clamped or both spindles have been turned manually (machine area is open,

drives are disconnected from supply).

• After the spindle enable signals are canceled, the two spindles coast to standstill at different

speeds if they are not mechanically coupled.

• A drive alarm occurs (internal follow-up mode):

DB31, ... DBX61.3 (follow-up mode active) = 1

When the alarm is cleared, the NC must not trigger any synchronization motion.

• A synchronization was not executed due to a synchronization lock of the following spindle:

DB31, ... DBX29.5 (Disable synchronization)

Basic procedure

If the following and leading spindles have fallen out of synchronism, or failed to synchronize at

all, synchronism can be restored between them by the following measures:

1. Set the axis enable signals and cancel synchronization disable signal if this has been set.

2. Start following spindle resynchronization with the NC/PLC interface signal:

DB31, ... DBX31.4 (resynchronization)

Only after the resynchronization process is complete can the setpoint-end synchronism be

fully restored.

3. Wait until the coupled spindles have synchronized.

Enable resynchronization

Setting the enabling signals closes the coupling at the current actual positions. The two

following NC/PLC interface signals are set:

DB31, ... DBX98.1 (coarse synchronism)

DB31, ... DBX98.0 (fine synchronism)

The following requirements must be fulfilled for resynchronization to work:

• The axis enabling signal must be set for the following spindle.

• The PLC must not set any synchronization disables for the following spindle:

DB31, ... DBX31.5 (Disable synchronization)

Resynchronize following spindle

Resynchronization is started for the relevant following spindle and commences as soon as the

low-high edge of following interface signal is detected:

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13.4 Special features

DB31, ... DBX31.4 (resynchronization)

The NC acknowledges the detection of the edge by outputting the NC/PLC interface signal:

DB31, ... DBX99.4 (synchronization running)

The interface signal "Synchronization running" is reset if:

• synchronization of the following spindle has been completed up to the stage at which there

is synchronism at the setpoint end.

• the NST DB31, ... DBX31.4 (resynchronization) was reset.

Response of synchronous signals during additional movements for the following spindle

The superimposed component is calculated to establish the synchronism signals.

Example

Program code

Comment

N51 SPOS=0 SPOS[2]=90

N52 OUPDEF(S2,S1,1,1,"FINE","DV")

N53 COUPON(S2,S1,77)

N54 M0

; Offset=77°, "coarse", "fine" synchro-

nous run signals exist.

N55 SPOS[2]=0 FA[S2]=3600

; Difference in speed, synchronism sig-

nals "coarse", "fine" are reported

N56 M0

; (note tolerances, see above)

; Offset=0°, "coarse", "fine" synchro-

nous run signals exist.

N60 M2=3 S2=500

; difference in speed, synchronism sig-

nals "coarse", "fine" are reported.

; offset undefined, synchronism signals

"coarse", "fine" are reported.

N65 M0

; (Note tolerances, see above)

Note

The axis enable signals can be canceled to interrupt a movement overlaid on the following

spindle (e.g. SPOS). This component of the movement is not affected by IS "NC/PLC interface

signal" DB31, ... DBX31.4 (resynchronization), but is restored by the REPOS operation.

Supplementary condition

IS DB31, ... DBX31.4 (resynchronization) has any effect only if there is a defined offset position

between the following spindle and leading spindle.

This is the case following COUPON with offset positions such as COUPON(...,77) or SPOS,

SPOSA, M19 for the following spindle with a closed coupling..

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13.4 Special features

13.4.3

Synchronous mode and NC/PLC interface signals

Note

During synchronous operation, the effect of the associated interface signal for the leading (LS)

or following spindle (FS) on the coupling must always be considered.

Spindle override (DB31, ... DBB19)

Only the spindle override value of the LS is active in synchronous operation.

Spindle disable (DB31, ... DBX1.3)

coupling

Response

off

Setpoints are output

off

No setpoint output for FS

off

No setpoint output for LS

off

No setpoint output for LS and FS

Setpoints are output

Spindle disable not effective for FS

Spindle disable also effective for FS, no setpoint output

No setpoint output for LS and FS

Controller enable (DB31, ... DBX2.1)

LS: Resetting the "controller enable" during synchronous operation

If the controller enable of the LS is reset during synchronous operation for active setpoint

coupling, a control-internal switching is made to the actual value coupling. If the controller

enable is reset while the LS is traversing, the LS is stopped and an alarm issued. Synchronous

operation remains active.

LS and FS: Selection of synchronous operation without controller enable

If the "controller enable" for LS and FS is not set for selected synchronous operation, it will be

activated. LS and FS, however, are not traversed until controller enable for LS and FS has been

granted.

LS and FS: Setting the "Controller enable"

The position assumed by a spindle with setting the "controller enable" depends on DB31, ...

DBX1.4 == <value> (follow-up operation):

<value>

Assumed spindle position

Position when controller enable is canceled

Current position

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13.4 Special features

Note

It is recommended for synchronous spindles during a block search, to write the DB31, ... DBX2.1

interface signal (controller enable) always together for FS and LS. If this is not done, the block

search, for example, stops after a FS machining because the controller enable of the LS is not

pending.

Note

Synchronism error

If the DB31, ... DBX2.1 interface signal (controller enable) is canceled for the FS after Spindle

Stop without the coupling being deactivated beforehand, then any synchronism error resulting

from external intervention will not be compensated when the "controller enable" is activated

again. This causes any programmed angular relationship between FS and LS to be lost.

The angular relationship can be restored by resynchronizing: DB31, ... DBX31.4 = 1

(resynchronization)

Follow-up mode (DB31, ... DBX1.4)

For follow-up operation, the set position is regularly set to the current actual position:

DB31, ... DBX1.4 == 1 (follow-up operation) AND DB31, ... DBX2.1 == 0 (controller enable)

⇒ Cyclic: Set position = actual position

Note

DB31, ... DBX1.4 (follow-up operation) is relevant only for DB31, ... DBX2.1 == 0 (controller

enable)

Position measuring system 1/2 (DB31, ... DBX1.5 and 1.6)

Switchover of the position measuring system for the FS and LS is possible during synchronous

operation. The coupling is retained.

Note

It is recommended to switchover the position measuring system for FS and LS only for

deselected synchronous operation.

Delete distance-to-go / spindle reset (DB31, ... DBX2.2)

LS: Setting spindle reset during synchronous operation

The setting of spindle reset causes the LS to be braked to standstill with the parameterized

acceleration. Synchronous operation remains active.

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13.4 Special features

Any superimposed movement, other than together with COUPON / COUPONC, will be completed

as fast as possible.

Spindle stop (feed stop) (DB31, ... DBX4.3)

LS and FS: Setting spindle stop during synchronous operation

The setting of "spindle stop" for FS or LS causes both spindles to be braked synchronous to

standstill. Synchronous operation remains active.

Resetting spindle stop

Once "spindle stop" has been reset for both spindles, reacceleration is made to the last valid

speed setpoint.

Application example

Bring FS and LS to a standstill when a protection door is opened during synchronous operation.

Signal characteristic for LS and FS:

1. Stop: DB31, ... DBX4.3 = 1 (spindle stop)

2. Waiting for standstill: DB31, ... DBX61.4 == 1

3. Stopping: DB31, ... DBX2.1 = 0 (controller enable)

Delete S value (DB31, ... DBX16.7)

LS: Delete S value during synchronous operation

If "delete S value" is set, the LS is braked to a standstill using a ramp. Synchronous operation

remains active.

FS: Delete S value during synchronous operation

The control interface signal does not have any function for the FS in synchronous operation.

Resynchronize spindle 1/2 (DB31, ... DBX16.4 and 16.5)

LS: Resynchronizing the position measuring system during synchronous operation

Note

It is recommended to resynchronize the position measuring system of the LS only for deselected

synchronous operation.

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13.4 Special features

Resynchronize (DB31, ... DBX31.4)

FS: Restoring the programmed angular offset

If synchronism between FS and LS is lost or not performed, the programmed angular offset can

be restored.

• Requirement: DB31, ... DBX31.4 = 1 (resynchronization)

• Acknowledgment: DB31, ... DBX99.4 == 1 (synchronization running)

Traverse keys for JOG (DB31, ... DBX4.6 and 4.7)

The "plus and minus traversing keys" for JOG are not disabled in the control for the FS in

synchronous operation, i.e. the FS executes a superimposed motion if one of these keys is

pressed.

Note

If superimposed traversing movements are to be precluded, they must be locked out by

measures in the PLC user program.

NC Stop axes plus spindles (DB21, ... DBX7.4)

"NC Stop axes plus spindles" in synchronous operation decelerates the coupled spindles in

accordance with the selected dynamic response. They continue to operate in synchronous

mode.

NC Start (DB21, ... DBX7.1)

(See Section "Response of the synchronous-spindle coupling for NC Start (Page 513)")

Note

NC Start after NC Stop does not deselect synchronous operation.

13.4.4

Differential speed between leading and following spindles

When does a differential speed occur?

A differential speed develops, e.g. with turning machine applications, when two spindles

oppose one other. Through the signed addition of two speed sources, a speed component is

derived from the leading spindle via the coupling factor. In addition to this, for the following

spindle a speed (S...) and a direction of rotation (M3/M4) can be programmed.

Generally, to achieve synchronous operation, a coupling factor is used with a value of '-1'. This

sign reversal then results in a differential speed for the following spindle as compared to an

additional programmed speed.

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13.4 Special features

This typical behavior in relation to the NC is illustrated in the following diagram.

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Example

Program code

Comment

N01 M3 S500

; S1 rotates in the positive direction with 500 rpm

; the master spindle is spindle 1

N02 M2=3 S2=300

; S2 rotates in the positive direction with 300 rpm

N05 G4 F1

N10 COUPDEF(S2,S1,-1)

; Coupling factor -1:1

N11 COUPON(S2,S1)

; Activate coupling. The speed of the following spindle

S2 results from the speed of the leading spindle S1 and

the coupling factor.

N26 M2=3 S2=100

; Programming the differential speed, S2 is the follow-

ing spindle.

Application

Manufacturing operations with positioned leading spindle and rotating tools require exact

synchronism with the counter spindle which then functions like a following spindle. A turret

rotating about the following spindle allows parts to be machined with different tool types.

The following diagram shows an application in which the tool is positioned parallel to the main

spindle.

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13.4 Special features

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Preconditions

Basic requirements for differential speed programming:

• Synchronous spindle functionality is required.

• The dynamic response of the following spindle must be at least as high as that of the leading

spindle. Otherwise, the system may suffer from reduced quality, for example, rigid tapping

without a compensating chuck G331/G332.

• The differential speed must be programmed in the channel in which the following spindle is

also configured. The leading spindle can be programmed in a different channel.

• The differential speed must be enabled for the following spindle by the PLC via IS "Enable

overlaid movement" (DB31, ... DBX26.4). If the enable signal has not been set, alarm 16771

"Channel% Following axis% Overlaid movement not enabled" is output. This alarm is cleared

when IS "Enable overlaid movement" (DB31, ... DBX26.4) is set or the coupling is opened.

Note

Positioning motion such as SPOS, SPOSA, M19 and axis motion do not have to be enabled.

Note

The differential speed does not therefore affect the coupling process.

The following or leading spindle cannot change gear stages while a coupling is active.

Activate coupling with COUPONC

When the coupling is activated, the following spindle is accelerated, as before, to the leading

spindle speed through application of the coupling factor. If the following spindle is already

rotating (M3, M4) when the coupling is activated, it continues with this motion after coupling.

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13.4 Special features

Deactivate coupling

If the coupling is deactivated, the following spindle continues to rotate at the speed

corresponding to the sum of both speed components. The spindle behaves as if it had been

programmed with the speed and direction transferred from the other spindle. When

deactivating, there are no differences to the previous behavior.

Differential speed

A differential speed results from the renewed programming of the following spindle (in the

example, S2=...) or M2=3, M2=4 in speed control mode during an active synchronous spindle

coupling or by adopting the speed of the following spindle for COUPONC.

Condition:

Speed S... must also be re-programmed with direction of rotation M3 or M4. Otherwise alarm

16111 "Channel% Block% Spindle% No speed programmed" is displayed.

Read offsets of following spindle

The current offset always changes when a differential speed is programmed. The current offset

can be read at the setpoint end with $AA_COUP_OFFS[Sn] and at the actual value end with

$VA_COUP_OFFS[Sn].

The last offset programmed returns the variable $P_COUP_OFFS[Sn].

Display differential speed

The programmed difference component is displayed as the speed setpoint for the programmed

differential speed (in our example, corresponds to 100 rpm).

The actual speed refers to the motor speed. In the example, the actual speed is 500 rev/min * (-1)

+ 100 rpm = -400 rev/min.

IS, NC to the PLC

Following spindle in speed-controlled operation

The IS "Spindle in setpoint range" (DB31, ... DBX83.5) is set for the following spindle by the NC

if the programmed speed difference (see previous example, N26 with M2=3 S2=100) is reached.

If a differential speed is programmed and not enabled by the PLC, this VDI interface signal is not

set.

Even if a differential speed has been programmed, the following spindle remains under position

control if this is required by the coupling.

Note

The axial VDI interface signal NC → PLC IS "Superimposed motion" (DB31, ... DBX98.4) is set

when the differential speed programming creates setpoints in addition to the coupling

setpoints.

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13.4 Special features

Actual direction of rotation clockwise (DB31, ... DBX83.7)

IS "Actual direction of rotation clockwise" (DB31, ... DBX83.7) refers to the resulting motor

direction.

IS PLC to the NC

Influence on following spindle via PLC interface

The effect of the axial VDI interface signals on the following spindle with differential speed in

speed control mode is described below:

Delete distance to go / Spindle Reset (DB31, ... DBX2.2)

The programmed differential speed and direction can be terminated by IS "Delete distance-to-

go / Spindle Reset" (DB31, ... DBX2.2). To delete the programmed speed only, it is possible to set

IS "Delete S value" (DB31, ... DBX16.7).

Resynchronize spindle 1/2 (DB31, ... DBX16.4 and 16.5)

The IS "Resynchronize spindle 1/2" (DB31, ... DBX16.4/16.5) are not locked. Any positional

offset is not compensated automatically by the coupling.

Invert M3/M4 (DB31, ... DBX17.6)

IS "Invert M3/M4" (DB31, ... DBX17.6) only inverts the additional programmed speed

component for the following spindle.

The motion component generated by the synchronous spindle coupling remains unaffected.

Spindle override (DB31, ... DBB19)

The "Spindle override" VDI interface (DB31, ... DBB19) only affects the additional programmed

speed component for the following spindle. If the spindle override switch is transferred to all

axial inputs, then any change in the spindle override value is applied twice to the following

spindle:

• once indirectly by a change in speed for the leading spindle and

• once in the programmed component of the following spindle.

The offset value can be adjusted accordingly in the PLC program.

Deselecting the coupling

If the coupling is deactivated, the following spindle continues to rotate at the speed

corresponding to the sum of both speed components. The motion transition upon coupling

deselection is at continuous speed.

With COUPOF , the spindle behaves as if it had been programmed with the speed and direction

transferred from the other spindle. In the example, this would be M4 S400.

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13.4 Special features

When COUPOFS is programmed, the following spindle is decelerated to standstill from the

current speed.

Activate additional functions

The following spindle can also be a master spindle. In this case, it is capable of additional

functions.

• Rotational feedrate with G95, G96 and G97. With G96 S2=... the "constant cutting speed" can

be activated for the following spindle.

The speed dependent on the position of the transverse axis is the setpoint speed for the

speed interpolator of spindle 2 and is therefore included in the total speed of S2.

• Rigid tapping without compensating chuck with G331, G332.

13.4.5

Behavior of synchronism signals during synchronism correction

Effect of synchronism correction

New synchronism signals are produced by comparing the actual values with the corrected

setpoints. Once a correction process has been undertaken, the synchronism signals should be

present again.

13.4.6

Delete synchronism correction and NC reset

Variable $AA_COUP_CORR[Sn] returns the value zero for different situations in which the

synchronism correct is deleted:

• Once a synchronized spindle coupling has been activated for the following in question

with COUPON(..)/COUPONC(..), an existing synchronism correction is adopted in the setpoint

position.

• A synchronism correction active during NC reset but not at the parts program end is adopted

in the setpoint position. This does not affect the synchronism signals.

• At M30, an existing synchronism correction is retained

• At the user end, the correction value can also be deleted at any early point by describing the

variable $AA_COUP_CORR with the value zero. The synchronism correction is removed

immediately and using a ramp with reduced acceleration rate if larger values are involved.

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13.4 Special features

13.4.7

Special points regarding start-up of a synchronous spindle coupling

Spindle start-up

The leading and following spindles must be started up initially like a normal spindle. The

corresponding procedure is described in:

Further information

Commissioning Manual CNC: NC, PLC, drive

Spindles (Page 377)

Requirements

The following parameters must then be set for the synchronous spindle pair:

• The machine numbers for the leading and following spindles

(for permanently configured coupling with channel-specific machine data MD21300

$MC_COUPLE_AXIS_1[n])

• The required coupling mode (setpoint, actual value or speed coupling)

(for permanently configured coupling with channel-specific machine data

MD21310 $MC_COUPLING_MODE_1[n])

• The gear stage(s) of FS and LS for synchronous operation

• The following coupling properties are still applicable for permanently configured

synchronous spindle coupling:

- Block change response in synchronous spindle operation:

MD21320 $MC_COUPLE_BLOCK_CHANGE_CTRL_1

- Coupling cancellation response:

MD21330 $MC_COUPLE_RESET_MODE_1

- Write-protection for coupling parameters:

MD21340 $MC_COUPLE_IS_WRITE_PROT_1

- Transformation parameters for synchronous spindle coupling:

SD42300 $SC_COUPLE_RATIO_1[n]

Command behavior of FS and LS for setpoint coupling

In order to obtain the best possible synchronism in setpoint couplings, the FS and LS must have

the same dynamic response as the response to setpoint changes. The axial control loops

(position, speed and current controllers) should each be set to the optimum value so that

variances can be eliminated as quickly and efficiently as possible.

The dynamic response adaptation function in the setpoint branch is provided to adapt

different axis dynamic responses without loss of control quality (see also Function Manual

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13.4 Special features

"Monitoring and Compensating", Section "K3: Compensations"). The following control

parameters must each be set optimally for the FS and LS:

• K_V factor (MD32200 $MA_POSCTRL_GAIN)

• Feedforward control parameters

MD32620 $MA_FFW_MODE

MD32610 $MA_VELO_FFW_WEIGHT

MD32650 $MA_AX_INERTIA

MD32800 $MA_EQUIV_CURRCTRL_TIME

MD32810 $MA_EQUIV_SPEEDCTRL_TIME

Behavior during loss of synchronism:

• Axis-specific MD32620 $MA_FFW_MODE

We recommend setting the feedforward control mode of the following axis to speed

feedforward control with Tt balancing MD32620 = 3.

This feedforward control mode can be further optimized for a more secure balancing process by

changing the axis-specific machine data:

Machine data

Meaning

MD32810 EQUIV_SPEEDCTRL_TIME

Equivalent time constant speed control loop for

feedforward control

MD37200 COUPLE_POS_TOL_COURSE

Threshold value for "Coarse synchronism"

MD37210 COUPLE_POS_TOL_FINE

Threshold value for "Fine synchronism"

MD37220 COUPLE_VELO_TOL_COURSE

Velocity tolerance 'coarse'

MD37220 COUPLE_VELO_TOL_FINE

Velocity tolerance 'fine'

In such cases, higher threshold values for the synchronism signals and larger position and/or

speed tolerances result in more stable results.

Dynamic response adaptation

To obtain a good control behavior, FS and LS must have the same dynamic response. The

following error for FS and LS must be equal at any given speed. For dynamically different

spindles, a matching via the dynamic response adaptation can be achieved in the setpoint

branch. The difference of the equivalent time constants between the dynamic "weakest" spindle

to the associated other spindle must be entered as time constant of the dynamic response

adaptation.

Example

When the speed feedforward control is active, the dynamic response is primarily determined by

the equivalent time constant of the "slowest" speed control loop.

• Equivalent time constant LS: MD32810 $MA_EQUIV_SPEEDCTRL_TIME[<LS>] = 5 ms

• Equivalent time constant FS: MD32810 $MA_EQUIV_SPEEDCTRL_TIME[<FS>] = 3 ms

• Time constant of dynamic response adaptation for FS: MD32910

$MA_DYN_MATCH_TIME[<FS>] = 5 ms - 3 ms = 2 ms

• Activation of the dynamic response adaptation for FS: MD32900

$MA_DYN_MATCH_ENABLE[<FS>] = 1

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13.4 Special features

The following error for FS and LS is identical for correctly set dynamic response adaptation:

Operating area "Diagnostics" > "Service axes"

For the optimization, it may be necessary to adjust servo gain factors or feedforward control

parameters slightly.

Position control parameter sets

In the case of spindles, each gear stage is assigned a position-control parameter set. These

parameter sets can be used to adapt the dynamic response for LS and FS in synchronous

operation. This requires that a different gear stage is used for speed and positioning operation

and synchronous operation. The associated gear stage must be switched before activating the

associated operating mode.

Control parameters

The following control parameters must be set identically for the FS and LS:

• MD33000 $MA_FIPO_TYPE (fine interpolator type)

• MD32400 $MA_AX_JERK_ENABLE (axial jerk limitation)

• MD32402 $MA_AX_JERK_MODE (filter type for axial jerk limitation)

• MD32410 $MA_AX_JERK_TIME (time constant for the axial jerk filter)

• MD32412 $MA_AX_JERK_FREQ (blocking frequency of the axial jerk filter)

• MD32414 $MA_AX_JERK_DAMP (damping of the axial jerk filter)

• MD32420 $MA_JOG_AND_POS_JERK_ENABLE (release jerk limitation)

• MD32430 $MA_JOG_AND_POS_MAX_JERK (axial jerk)

FS: Automatic parameterization of the control parameters

The control parameters of the following spindle can be set as follows using this machine data:

MD30455 $MA_MISC_FUNCTION_MASK

Bit 5=0: Synchronous spindle coupling, following spindle:

Position control, feedforward control and parameter block are set for the following spindle.

Bit 5=1: Synchronous spindle coupling:

The control parameters of the following spindle are set as in an uncoupled scenario.

Further information

Velocities, setpoint/actual value systems, closed-loop control (Page 135)

Automatic transfer of the LS parameters for synchronous operation

For the automatic dynamic response adaptation for FS and LS, for synchronous operation, the

parameter values for the position control, feedforward control and parameter records of the FS

can be transferred from the LS:

MD30455 $MA_MISC_FUNCTION_MASK, Bit 5

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13.4 Special features

Separate dynamic response for spindle and axis operations

In spindle and axis operations, dynamic programming FA, OVRA, ACC and VELOLIMA can be set

separately from one another with the following MD:

MD30455 $MA_MISK_FUNCTION_MASK Bit 6=0

Assignment is undertaken by the programmed axis or spindle name. For example, in spindle

operation, VELOLIMA[S1]=50 therefore only reduces the maximum speed to 50% and in axis

operation, VELOLIMA[C]=50 only reduces the maximum speed to 50%.

If, for example, VELOLIMA[S1]=50 and VELOLIMA[C]=50 are to have the same effect as before

with this machine data, the programming of FA, OVRA, ACC and VELOLIM have an effect

regardless of the programmed names:

MD30455 $MA_MISK_FUNCTION_MASK Bit 6=1

Knee-shaped acceleration characteristic

For the leading spindle, the effect of a knee-shaped acceleration characteristic on the following

spindle is identified by the following axis-specific machine data:

• MD35220 $MA_ACCEL_REDUCTION_SPEED_POINT (speed for reduced acceleration) and

• MD35230 $MA_ACCEL_REDUCTION_FACTOR (reduced acceleration).

If MD35242 $MA_ACCEL_REDUCTION_TYPE is present, it is also used to configure the type of

acceleration reduction. Otherwise a hyperbolic drop in acceleration is assumed.

If the dynamic response of a following spindle is lower than that of the leading spindle when the

coupling factor is taken into account, the leading spindle dynamic response is reduced to the

required level while the coupling is active.

The acceleration should be constant over the entire speed range for the following spindle.

However, if a knee-shaped acceleration characteristic is also stored in the above-mentioned

machine data for the following spindle, this is only taken into account when the spindles are

coupled in. The setpoints of the following spindle are applied for the specified knee-shaped

acceleration characteristic.

Further information

Acceleration and jerk (Page 79), knee-shaped acceleration characteristic

Actual value coupling

In an actual value coupling (AV), the drive for the FS must be considerably more dynamic than

the leading spindle drive. The individual drives in an actual value coupling are also set optimally

according to their dynamic response.

An actual value coupling should only be used in exceptional cases.

Speed coupling

The velocity coupling (VV) corresponds internally to a setpoint coupling (DV), but with lower

dynamic requirements of the FS and LS. A position control servo loop is not required for the FS

and/or LS. Measuring systems are not required.

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13.4 Special features

Threshold values for coarse/fine synchronism

After controller optimization and feedforward control setting, the threshold values for coarse

and fine synchronism must be entered for the FS.

• Threshold value for "Coarse synchronism"

Axis-spec. MD7200: AV, DV: COUPLE_POS_TOL_COARSE

MD37220: VV: COUPLE_VELO_TOL_COARSE

• Threshold value for "Fine synchronism"

Axis-spec. MD37210: AV, DV: COUPLE_POS_TOL_FINE

MD37230: VV: COUPLE_VELO_TOL_FINE

The values of the FS must be calculated according to the accuracy requirements of the machine

manufacturer, and the PLC interface must be checked via the service display.

Angular offset LS/FS

If there must be a defined angular offset between the FS and LS, e.g. when synchronous

operation is activated, the "zero degree positions" of the FS and LS must be mutually adapted.

This can be done with the following machine data:

• MD34100 $MA_REFP_SET_POS

• MD34080 $MA_REFP_MOVE_DIST

• MD34090 $MA_REFP_ MOVE_DIST_CORR

Further information

Homing (Page 31)

Service display for FS

In the "Diagnostics" operating area, when commissioning in the synchronous mode, the

following values are displayed for the following spindle:

• Actual deviation between setpoints of FS and LS

Value displayed: Position offset in relation to leading spindle (setpoint)

(value corresponds to angular offset between FS and LS that can be read with axis variable

$AA_COUP_OFFS in the part program)

• Actual deviation between actual values of FS and LS

Value displayed: Position offset in relation to leading spindle (actual value)

Further information

Operating Manual

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13.6 Examples

13.5

Boundary conditions

Availability of the "synchronous spindle" function

The function is an option ("synchronous spindle/multi-edge turning" or the corresponding

optional version of the generic coupling), which must be assigned to the hardware via the

license management.

Note

For information on the different versions of generic coupling, see:

Further information

Axis couplings (Page 537)

13.6

Examples

Programming example

Program code

Comment

; Leading spindle = master spindle = spindle 1

; Following spindle = spindle 2

N05 M3 S3000 M2=4 S2=500

; Master spindle rotates at 3000 rpm

; FS: 500 rpm

N10 COUPDEF (S2, S1, 1, 1, "No",

; Def. of coupling, can also

"Dv")

; be configured

N70 SPCON

; Include leading spindle in the position con-

trol

; (setpoint value coupling).

N75 SPCON(2)

; Bring following spindle into closed-loop po-

sition control

N80 COUPON (S2, S1, 45)

; On-the-fly coupling to offset position = 45

degrees

N200 FA [S2] = 100

; Positioning speed = 100 degrees/min

N205 SPOS[2] = IC(-90)

; Traverse with 90° overlay in negative direc-

tion

N210 WAITC(S2, "Fine")

; Wait for "fine" synchronism

N212 G1 X.., Y.. F...

; Machining

N215 SPOS[2] = IC(180)

; Traverse with 180° overlay in positive direc-

tion

N220 G4 S50

; Dwell time = 50 revolutions

; of master spindle

N225 FA [S2] = 0

; Activate configured velocity (MD)

N230 SPOS[2] = IC (-7200)

; 20 rev. with configured velocity

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13.7 Data lists

Program code

Comment

; in neg. direction

N350 COUPOF (S2, S1)

; On-the-fly decoupling, S = S2 = 3000

N355 SPOSA[2] = 0

; Stop FS at zero degrees

N360 G0 X0 Y0

N365 WAITS(2)

; Wait for spindle 2

N370 M5

; Stop FS

N375 M30

13.7

Data lists

13.7.1

Machine data

13.7.1.1

NC-specific machine data

Number

Identifier: $MN_

Description

10000

AXCONF_MACHAX_NAME_TAB

Machine axis name

13.7.1.2

Channelspecific machine data

Number

Identifier: $MC_

Description

20070

AXCONF_MACHAX_USED

Machine axis number valid in channel

21300

COUPLE_AXIS_1

Definition of synchronous spindle pair

21310

COUPLING_MODE_1

Type of coupling in synchronous spindle mode

21320

COUPLE_BLOCK_CHANGE_CTRL_1

Block change behavior in synchronous spindle operation

21330

COUPLE_RESET_MODE_1

Coupling abort behavior

21340

COUPLE_IS_WRITE_PROT_1

Coupling parameters are write-protected

13.7.1.3

Axis/spindlespecific machine data

Number

Identifier: $MA_

Description

30455

MISK_FUNCTION_MASK

Axis functions

30550

AXCONF_ASSIGN_MASTER_CHAN

Reset position of channel for axis change

32200

POSCTRL_GAIN

Servo gain factor (K_V factor)

32400

AX_JERK_ENABLE

Axial jerk limitation

32410

AX_JERK_TIME

Time constant for axial jerk filter

32420

JOG_AND_POS_JERK_ENABLE

Initial setting for axial jerk limitation

32430

JOG_AND_POS_MAX_JERK

Axial jerk

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13.7 Data lists

Number

Identifier: $MA_

Description

32610

VELO_FFW_WEIGHT

Feedforward control factor for speed feedforward control

32620

FFW_MODE

Feedforward control mode

32650

AX_INERTIA

Moment of inertia for torque feedforward control

32800

EQUIV_CURRCTRL_TIME

Equivalent time constant current control loop for feed-

forward control

32810

EQUIV_SPEEDCTRL_TIME

Equivalent time constant speed control loop for feedfor-

ward control

34080

REFP_MOVE_DIST

Reference point approach distance

34090

REFP_MOVE_DIST_CORR

Reference point offset

34100

REFP_SET_POS

Reference point value

35000

SPIND_ASSIGN_TO_MACHAX

Assignment of spindle to machine axis

37200

COUPLE_POS_TOL_COARSE

Threshold value for "Coarse synchronism"

37210

COUPLE_POS_TOL_FINE

Threshold value for "Fine synchronism"

37220

COUPLE_VELO_TOL_COARSE

Speed tolerance "coarse" between leading and following

spindles

37230

COUPLE_VELO_TOL_FINE

Speed tolerance "fine" between leading and following

spindles

13.7.2

Setting data

13.7.2.1

Channelspecific setting data

Number

Identifier: $SC_

Description

42300

COUPLE_RATIO_1

Transmission parameters for synchronous spindle operation

13.7.3

System variables

System variable

Description

$P_COUP_OFFS[following spindle]

Programmed offset of the synchronous spindle

$AA_COUP_OFFS[following spindle]

Position offset for synchronous spindle (setpoint)

$VA_COUP_OFFS[following spindle]

Position offset for synchronous spindle (actual value)

For exhaustive explanations of the system variables, see:

Further information

List Manual System Variables

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14.1

Coupled motion

14.1.1

Brief description

14.1.1.1

Function

The "coupled motion" function enables the definition of simple axis links between a master axis

and a slave axis, taking into consideration a coupling factor.

Coupled motion has the following features:

• Any axis of the NC can be defined as a master axis.

• Any axis of the NC can be defined as a coupled axis with a specific coupling factor.

• The master axis and coupled motion axis or axes together form a coupled axis grouping.

• Any number of coupled motion axes can be assigned to a master axis.

• A total of 2 leading axes may be assigned to each coupled motion axis.

• A coupled motion axis can be the master axis of a further coupled axis grouping.

• Traversing movements of the master axis are executed in synchronism on all slave axes based

on the coupling factor.

• Coupled motion axes can be moved independently of the master axis while the coupling is

active (overlaid movements).

• The master and coupled motion axes of a coupled axis grouping are defined, and the coupling

switch on/switch off, by programming instructions in the part program or by synchronized

action.

• Coupled motion is also possible in the following manual modes: JOG, JOG REF, JOG INC, etc.

14.1.1.2

Preconditions

"Coupled motion" function

The "Coupled motion" function is a fixed component of the NC software.

Generic coupling

The coupled motion functionality is also available in the generic coupling.

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14.1 Coupled motion

However, for basic operation of generic coupling, the following restrictions apply:

• The maximum number of coupled motion groupings is limited to 4.

• Only 1 leading axes may be assigned to each coupled motion axis.

• Cascading is not possible.

Note

These restrictions do not apply when NC software is supplied with the relevant options of

generic coupling (refer to " Preconditions (Page 609) " in the "Brief description" of generic

coupling).

14.1.2

General functionality

The "Coupled motion" function allows the definition of simple axis couplings. Coupling is

performed from one leading axis to one or more following axes, the so-called coupled motion

axes. A separate coupling factor can be specified for each coupled motion axis.

Coupled axis grouping

The leading axis and all the coupled motion axes assigned to it together form a coupled axis

grouping. If the leading axis is traversed, all coupled motion axes traverse in accordance with

their coupling factors.

A coupled axis grouping can consist of any combination of linear and rotary axes.

Leading axes

Any axis of the NC, including simulated axes, can be used as leading axis.

Coupled axes

Any axis of the NC can be used as coupled motion axis.

Coupling factor

The ratio in which the coupled motion axis moves in relation to the leading axis is specified via

the coupling factor:

Coupling factor K = motion of the coupled motion axis / motion of the leading axis

Negative coupling factors (motion of the coupled motion axis in the opposite direction) are also

permitted.

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14.1 Coupled motion

;

Leading axis

Coupled-motion axis

Coupling factor

Coupled-motion Y axis

V axis

grouping ①

Coupled-motion Z axis

W axis

-1

grouping ②

Figure 14-1

Application example: Two-sided machining

Multiple couplings

Up to 2 leading axes can be assigned to one coupled motion axis. The traversing movement of

the coupled motion axis then results from the sum of the traversing movements of the leading

axes.

Dependent coupled motion axis

A coupled motion axis is a "dependent coupled motion axis" when it traverses as a result of a

leading axis movement.

Independent coupled motion axis

A coupled motion axis is an "independent coupled motion axis" when it traverses as a result of

a direct traverse instruction. The traversing movement resulting from the coupled motion axis

is then the sum total of the traversing movements as a "dependent" and an "independent"

coupled motion axis.

Coupled motion axis as leading axis

A coupled motion axis can at the same time be the leading axis of a further coupled axis

grouping.

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14.1 Coupled motion

Coordinate system

Coupled axis motion is always executed in the base coordinate system (BCS).

Activating/deactivating

Coupled motion can be activated/deactivated via the part programs and synchronous actions. In

this context please ensure activating/deactivating is undertaken with the same programming:

• Activate: Part program → Deactivate: Part program

• Activate: Synchronous action → Deactivate: Synchronized action

Synchronization on-the-fly

If switch on is performed while the leading axis is in motion, the coupled motion axis is first

accelerated to the velocity corresponding to the coupling. The position of the leading axis at the

time the velocities of the leading and coupled motion axes are synchronized then serves as the

start position for further coupled motion.

Operating modes

Coupled motion is effective in the AUTOMATIC, MDA and JOG modes.

Reference point approach

The following applies for referencing of axes of a coupled axis grouping:

• Leading axes

When referencing the leading axis of a coupled axis grouping, the coupling to all coupled

motion axes is retained. The coupled motion axes move in synchronism with the leading axis,

as a function of their coupling factors.

• Coupled motion axis: JOG/REF mode

When referencing a coupled motion axis of a coupled axis grouping, the coupling to the

leading axis is cancelled. If the coupling is canceled, the following alarm is displayed:

Alarm 16772 "Channel Channel No. Block Block No. Axis Axis No. is following axis, coupling

is opened."

The coupling is not activated again until JOG/REF mode is cancelled.

The display of this alarm can be suppressed using the following machine data:

MD11410 $MN_SUPPRESS_ALARM_MASK, Bit 29 = 1 (mask supporting special alarm

generation)

CAUTION

No coupling

When the coupled motion axis is referenced, the coupling to the leading axis is cancelled.

If referencing is executed immediately with the leading axis, i.e. without changing JOG/REF

mode, the coupled motion axis does not traverse with the leading axis.

• Coupled motion axis: Part program command G74

It is not possible to reference a coupled motion axis of a coupled axis grouping using the G74

programming instruction.

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14.1 Coupled motion

Distance-to-go: Coupled-motion axis

The distance-to-go of a coupled motion axis refers to the total residual distance to be traversed

from dependent and independent traversing.

Delete distance-to-go: Coupled-motion axis

Delete distance-to-go for a coupled motion axis only results in aborting of the independent

traversing movement of the leading axis.

Response to NC Start

The behavior of the coupled-axis groupings during NC Start depends on the setting in the

machine data:

MD20112 $MC_START_MODE_MASK (definition of initial control settings for NC-START)

Bit

Value

Meaning

Coupled-axis groupings are maintained in NC Start.

Coupled-axis groupings are phased out in NC Start.

Response to RESET/part program end

The behavior of the coupled-axis groupings during RESET/ part program end depends on the

setting in the machine data:

MD20110 $MC_RESET_MODE_MASK (definition of initial control settings after RESET / TP end)

Bit

Value

Meaning

Coupled-axis groupings are invalidated on RESET / part program end.

Coupled-axis groupings remain active even beyond RESET/part program end.

Note

If with NC RESET or end of part program in a channel, the leading axis is not stopped as well

(cross-channel coupling, command axis, PLC axis, etc.), the requested RESET cannot be

completed.

Because of traversing of the leading axis, the coupled-motion axis is still active for the channel

in which the RESET is requested. With suitable actions (NC RESET in the channel of the leading

axis, stopping of the command or PLC axis), the leading axis must also be stopped in parallel to

the coupled-motion axis.

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14.1 Coupled motion

14.1.3

Programming

14.1.3.1

Definition and switch on of a coupled axis grouping (TRAILON)

Definition and switch on of a coupled axis grouping take place simultaneously with

the TRAILON part program command.

Programming

Syntax:

TRAILON(<coupled motion axis>, <leading axis>,

[<coupling factor>])

Effectiveness:

modal

Parameters:

Coupled motion Type: AXIS

axis:

Range of values: All defined axis and spindle names in the channel

Leading axis:

Type: AXIS

Range of values: All defined axis and spindle names in the channel

Coupling factor: The ratio of the traversing movement of the coupled motion axis to the

leading axis is specified via the optional coupling factor:

Coupling factor = Path of the coupled-motion axis/path of the leading

axis

A negative coupling factor results in motion in opposite directions for

the leading and coupled motion axis.

Type: REAL

Range of values: ± (2,2 * 10-308 … 1,8 * 10+308)

Default value:

+1.0

Example:

Program code

Comment

TRAILON(V,Y,2)

; Definition and switch on of the coupling of the

coupled-motion axis V with leading axis Y. The

coupling factor is 2.

14.1.3.2

Switch off (TRAILOF)

Switch off of the coupling of a coupled-motion axis with a leading axis takes place through

the TRAILOF part program command.

Programming

Syntax:

TRAILON(<coupled motion axis>, <leading axis>)

TRAILOF(<coupled-motion axis>)

Effectiveness:

modal

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14.1 Coupled motion

Parameters:

Coupled motion Type: AXIS

axis:

Range of val- All defined axis and spindle names in the channel

ues:

Leading axis:

Type: AXIS

Range of val- All defined axis and spindle names in the channel

ues:

Example:

Program code

Comment

TRAILOF(V,Y)

;

Deactivation of the coupling of the coupled-motion

;

axis

V to leading axis Y.

14.1.4

Effectiveness of PLC interface signals

Independent coupled motion axis

All the associated channel and axis specific interface signals of the coupled-motion axis are

effective for the independent motion of a coupled-motion axis, e.g.:

• DB21, ... DBX0.3 (Activate DRF)

• DB31, ... DBX0.0 - 0.7 (feedrate override)

• DB31, ... DBX1.3 (axis blocking)

• DB31, ... DBX2.1 (control system enable)

• DB31, ... DBX4.0 - 4.2 (activate handwheel)

• DB31, ... DBX4.3 (feed stop)

•

…

This allows the speed to be changed for the independent motion of a coupled motion axis using

a feedrate override or a DRF offset to be defined using the handwheel in AUTOMATIC and MDA

modes.

Dependent coupled motion axis

With respect to the motion of a coupled motion axis, which is dependent on the leading axis,

only the coupled-motion axis interface signals that effect termination of the motion (e.g. axis-

specific feed stop, axis inhibit, control system enable, etc.) are effective.

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14.1 Coupled motion

Leading axis

When a coupled axis grouping is active, the interface signals (IS) of the leading axis are applied

to the appropriate coupled motion axis via the axis coupling, i.e.

• A position offset or feed control action of the leading axis is applied via the coupling factor to

effect an appropriate position offset or feed control action in the coupled motion axis.

• Shutdown of the leading axis as the result of an interface signal (e.g. axis-specific feed stop,

axis inhibit, servo enable, etc.) causes the corresponding coupled motion axis to shut down.

Position measuring system 1/2 (DB31, ... DBX1.5/1.6))

Switch-over of the position measuring system for the leading and coupled motion axes is not

inhibited for an active coupled axis grouping. The coupling is not canceled.

Recommendation: Switch-over when the coupling is deactivated.

Tracking (DB31, ... DBX1.4)

Activation of tracking for an axis is done via the PLC program by setting the following NC/PLC

interface signals:

DB31, ... DBX2.1 = 0 (control system enable)

DB31, ... DBX1.4 == 1 (tracking mode)

When activating tracking mode for a coupled axis grouping, the specified NC/PLC interface

signals must be set simultaneously for all axes (master and slave axes) of the coupled axis group.

If tracking mode is activated for the master axis only, a permanent offset results within the

coupling.

Whether and which axis is a leading or a following axis can be seen from the following NC/PLC

interface signals and system variables:

DB31, ... DBX99.0 (leading axis/spindel active)

DB31, ... DBX99.1 (following axis/spindel active)

$AA_COUP_ACT[axis name] (see: Status of coupling)

14.1.5

Status of coupling

The coupling status of an axis can be determined using the following system variables:

$AA_COUP_ACT [axis name]

Value

Meaning

No coupling active

1, 2, 3

Tangential tracking

Synchronous spindle coupling

Coupled motion active

Master value coupling

Following axis of electronic gearbox

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14.1 Coupled motion

Note

Only one coupling mode may be active at any given time.

14.1.6

Dynamics limit

The dynamics limit is dependent on the type of activation of the coupled axis grouping:

• Activation in part program

If activation is performed in the part program and all leading axes are active as program axes

in the activating channel, the dynamic response of all coupled-motion axes is taken into

account during traversing of the leading axes to avoid overloading the coupled-motion axes.

If activation in part program takes place with leading axes that are not active as program axes

in the activating channel ($AA_TYP ≠ 1), then the dynamics of the coupled motion axes is not

considered while traversing the leading axes. This can result in an overload for coupled

motion axes with a dynamic response which is less than that required for the coupling.

• Activation in synchronized action

If activation is performed in a synchronous action, dynamics of the coupled motion axes is

not taken into account during traversing of the leading axis. This can result in an overload for

coupled motion axes with a dynamic response which is less than that required for the

coupling.

CAUTION

Axis overload

If a coupled motion grouping

• in synchronized actions

• is activated in the part program with leading axes, that are not program axes in the

channel of the coupled motion axes,

it is the special responsibility of the user/machine manufacturer to provide suitable

measures to ensure that an overload of the coupled motion axes does not occur through

traversing of the leading axis.

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14.1 Coupled motion

14.1.7

Supplementary conditions

Control system dynamics

It is recommended to align the position control parameters of the leading axis and the coupled

motion axis within a coupled axis group.

Note

Alignment of the position control parameters of the leading axis and the coupled motion axis

can be performed via a parameter set changeover.

14.1.8

Examples

Application Example: Two-sided machining

;

Example 1

Example of an NC part program for the axis constellation shown in Fig.:

Program code

Comment

TRAILON(V,Y,1)

; Activation of 1st coupled axis group

TRAILON(W,Z,-1)

; Activation of 2nd coupled axis group

G0 Z10

; Infeed Z and W axes in opposite axial directions

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14.2 Curve tables

Program code

Comment

G0 Y20

; Infeed of Y and V axes in same axis

direction

G1 Y22 V25

; Superimpose dependent and independent movement of coupled

motion axis "V"

TRAILOF(V,Y)

; Deactivate 1st coupled axis group

TRAILOF(W,Z)

; Deactivate 2nd coupled axis group

Example 2

The dependent and independent movement components of a coupled motion axis are added

together for the coupled motion. The dependent component can be regarded as a co-ordinate

offset with reference to the coupled motion axis.

Program code

Comment

N01 G90 G0 X100 U100

;

N02 TRAILON(U,X,1)

; Activation of coupled axis group

N03 G1 F2000 X200

; Dependent movement of U, Upos=200, UTrail=100

N04 U201

; Independent movement, Upos=U201+UTrail=301

N05 X250

; Dependent movement of U, UTrail=UTrail(100)+50=150,

Upos=351

N06 G91 U100

; Independent movement of Upos(351)+U100=451

N07 G90 X0

; Dependent movement of U, Upos=Upos(451)-UTrail(250)=201

N10 TRAILOF(U,X)

14.2

Curve tables

14.2.1

Product brief

14.2.1.1

Function

The "curve tables" function can be used to define the complex sequence of motions of an axis in

a curve table.

Any axis can be defined as a leading axis and a following axis can be traversed by taking a curve

table into account.

The command variable in these motion sequences is an abstract master value, which is

generated by the control or derived from an external variable (e.g. simulated position of an axis).

Creating curve tables is performed via part program sequences.

The curve tables in the static NC memory remain valid after the part program has been been

closed or after POWER DOWN.

Curve tables can be saved in dynamic NC memory for faster access. Please note that tables need

to be reloaded after run-up.

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Axis groupings with curve tables must be reactivated independently of the storage location of

the curve table after POWER ON.

Linear curve table segments are stored in separate areas to save memory space.

14.2.1.2

Preconditions

Memory configuration

Static NC memory

Memory space for curve tables in static NC memory is defined by machine data:

MD18400 $MN_MM_NUM_CURVE_TABS (number of curve tables)

MD18402 $MN_MM_NUM_CURVE_SEGMENTS (number of curve segments)

MD18403 $MN_MM_NUM_CURVE_SEG_LIN (number of linear curve segments)

MD18404 $MN_MM_NUM_CURVE_POLYNOMS (number of curve table polynomials)

Dynamic NC memory

Memory space for curve tables in dynamic NC memory is defined by machine data:

MD18406 $MN_MM_NUM_CURVE_TABS_DRAM (number of curve tables)

MD18408 $MN_MM_NUM_CURVE_SEGMENTS_DRAM (number of curve segments)

MD18409 $MN_MM_NUM_CURVE_SEG_LIN_DRAM (number of linear curve segments)

MD18410 $MN_MM_NUM_CURVE_POLYNOMS_DRAM (number of curve table polynomials)

14.2.2

General functionality

Curve table

A functional relation between a command variable "master value" and an abstract following

value is described in the curve table.

A following variable can be assigned uniquely to each master value within a defined master

value range.

Curve segment

The functional relation can be subdivided into separate sections of the master value axes, called

curve segments.

Within a curve segment, the relation between the master value and following value is generally

described by a polynomial up to the third order. Polynomials up to the 5th degree are also

permissible.

Further information: NC Programming Programming Manual

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Curve segments are used if:

• Polynomials or circles are programmed

• Spline is active

• Compressor is active

• Polynomials or circles are generated internally (chamfer/rounding, approximate positioning

with G643, TRC, etc.)

Tool radius compensation

Curve tables are available in which it is possible to specify the tool radius compensation in the

table definition even if polynomial blocks or blocks with no motion for an axis, or jumps for the

following axis, occur in the curve table (G41/G42/G40 in the table definition).

The equidistant curve (tool center point path of tool radius compensation) of a curve consisting

of polynomials can no longer be displayed exactly using polynomials. The associated curve

tables must be approximated stepwise, using polynomials in this case. This means that the

number of segments in the curve table no longer matches the number of programmed

segments. The number of segments required for the curve table is defined by the bend of the

curve. The larger the curvature for the programmed curve, the more segments are required for

the curve table.

On account of tool radius compensation for curve tables, more memory may be required.

Selection option of the memory type should not produce shortage of static NC memory.

Selection of memory type

While defining a curve table, it can be defined whether the curve table is created in the static or

dynamic NC memory.

Note

Table definitions in the static NC memory are available even after control system run-up. Curve

tables of the dynamic NC memory must be redefined after every control system run-up.

14.2.3

Memory organization

Memory configuration

The storage place available for the curve table in the static and dynamic NC memory is defined

during memory configuration (see Section "Memory configuration (Page 551)").

Memory optimization

In a curve table with linear segments, the linear segments can be stored efficiently in the

memory only if the two following machine data items are > 0:

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MD18403 $MC_MM_NUM_CURVE_SEG_LIN (number of linear curve segments in the static NC

memory)

MD18409 $MC_MM_NUM_CURVE_SEG_LIN_DRAM (number of linear curve segments in the

dynamic NC memory)

If no memory areas are created with this machine data, then the linear segments are stored as

polynomial segments.

Alarm in case of insufficient memory

If memory has been configured for tables with linear and polynomial segments via machine data

and memory for linear segments runs out when generating a linear table, the the memory for

polynomial segments is used for the linear segments (if available). In this case, memory is

"wasted", as a polynomial segment requires an unnecessary amount of memory to store a linear

segment. This circumstance is conveyed through an alarm, which also discloses the number of

unnecessarily used polynomial segments. The alarm only displays awarning and does not result

in the interruption of the program or the generation of the curve table.

If a curve table consists of linear segments and polynomials of a high degree, a memory area for

linear segments and a memory area for polynomial segments is required for the storage of the

curve table. An alarm is output if insufficient memory is available in the relevant areas. The alarm

parameters can be used to detect the resources that are insufficient.

Insufficient memory

If a curve table cannot be created, because sufficient memory is not available, then the newly

created table is deleted immediately after the alarm.

If insufficient is available, then one or more table(s) that is/are no longer required can be deleted

with CTABDEL or, alternatively, memory can be reconfigured via machine data.

Temporary curve table

When a curve table is created, a temporary curve table is set up first in memory, which is then

extended block by block. Finally (CTABEND), the table is checked for consistency. The temporary

table is converted to a table that can be used in a coupling only if it is found to be consistent.

Same table number

A new curve table may have the same number as an existing table. The new curve table then

overwrites the existing table with the same number. This is done only if the new curve table does

not contain any errors. If an error is detected in the new table, the old table is not overwritten.

If the user wishes to have the option of overwriting an existing curve table without deleting it

first, then he will need to dimension the table memory so that there is always enough extra

memory to accommodate the table to be overwritten.

Overwriting curve tables

Curve tables that are not active in a master value coupling and are locked with CTABLOCK() may

be overwritten.

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Deleting curve tables

Curve tables that are not active in a master value coupling and are locked with CTABLOCK() may

be overwritten.

14.2.4

Commissioning

14.2.4.1

Memory configuration

A defined storage space is available for the curve tables in the static and dynamic NC memory,

which is defined through the following machine data:

Static NC memory

MD18400 $MN_MM_NUM_CURVE_TABS

Defines the number of curve tables that can be stored in the

static NC memory.

MD18402 $MN_MM_NUM_CURVE_SEGMENTS

Defines the number of curve table segments that can be stored

in the static NC memory.

MD18403 $MN_MM_NUM_CURVE_SEG_LIN

Defines the maximum number of linear segments in the static

NC memory.

MD18404 $MN_MM_NUM_CURVE_POLYNOMS

Defines the number of curve table polynomes that can be

stored in the static NC memory.

Dynamic NC memory

MD18406 $MN_MM_NUM_CURVE_TABS_DRAM

Defines the number of curve tables that can be stored in the

dynamic NC memory.

MD18408 $MN_MM_NUM_CURVE_SEGNENTS_DRAM

Defines the number of curve table segments that can be stored

in the dynamic NC memory.

MD18409 $MN_MM_NUM_CURVE_SEG_LIN_DRAM

Defines the maximum number of linear segments in the dy-

namic NC memory.

MD18410 $MN_MM_NUM_CURVE_POLYNOMS_DRAM

Defines the number of curve table polynomes that can be

stored in the dynamic NC memory.

Note

A curve table with linear segments can be stored efficiently in the memory only if:

MD18403 > 0 or MD18409 > 0

If no memory areas are created with this machine data, then the linear segments are stored as

polynomial segments.

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14.2.4.2

Tool radius compensation

MD20900

Tool radius compensation can produce segments for which the following axis or leading axis

have no movement. A missing movement of the following axis does not normally represent any

problem. As against this, a missing movement of the leading axis requests a specification as to

how such discontinuities are to be handled, i.e., whether or not a curve table should be

generated in these cases. This specification is done in the machine data settings:

MD20900 $MC_CTAB_ENABLE_NO_LEADMOTION (curve tables with discontinuity of the

following axis)

Value

Description

No curve tables that contain a discontinuity in the following axis are produced. Alarm 10949 is

output and program processing is aborted.

Curve tables with a discontinuity in the following axis can be generated. If a segment contains

a discontinuity in the following axis, Alarm 10955 is output but program processing is contin-

ued.

Curve tables with a discontinuity in the following axis can be created without an alarm being

output.

Note

In the case of a curve table that contains segments without leading axis movement (this means

that the following axis jumps at this point), the following axis can only make a jump within its

dynamic limits (max. velocity and max. acceleration). This means that there is always a deviation

from the programmed curve.

14.2.4.3

Specification of memory type

MD20905

If there is no memory specification while defining or deleting a curve table, the memory type can

be determined through the following machine data:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE (default memory type for curve tables)

Value

Description

Curve tabels are normally created in the static NC memory.

Curve tabels are normally created in the dynamic NC memory.

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14.2.5

Programming

Definition

The following modal language commands work with curve tables: (The parameters are

explained at the end of the list of functions.)

• Beginning of definition of a curve table:

CTABDEF(following axis, leading axis, n, applim, memType)

• End of definition of a curve table:

CTABEND()

• Deleting curve table(s):

CTABDEL(n)

; curve table n

CTABDEL(n, m)

; [n < m], more than one in the range of numbers

; it is deleted in static "SRAM" and in dynamic "DRAM" of NC memory.

• CTABDEL(n, m, memType)

; Delete with memory specification:

Those curve tables with the numbers in the range, which are in the specified memory type,

will be deleted. All other curve tables are retained.

Delete all tables in a particular memory type:

CTABDEL(, , "DRAM")

CTABDEL(, , "SRAM")

CTABDEL()

; all in DRAM or

; all in SRAM:

; all, irrespective of memory type

• Read the following value for a master value

CTAB(master value, n, degrees, [following axis, lead axis])

• Read the master value for a following value

CTABINV(following value, approx. master value, n, degrees, [following axis, leading axis])

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Access to curve table segments

• Read start value (following axis value) of a table segment

CTABSSV(leading value, n, degrees, [following axis, leading axis])

• Read end value (following axis value) of a table segment

CTABSEV(master value, n, degrees, [following axis, master axis])

Note

If curve table functions such as CTAB(), CTABINV(), CTABSSV() etc., in synchronized

actions are used, only main traverse variable, e.g. $AC_PARAM[ ... ] or $R[ ... ] is permissible

for the return value and the argument "degrees" of the function.

Example:

ID=1 WHEN TRUE DO $R1 = CTABSSV(10, 1, $R2)

ID=1 WHEN TRUE DO $AC_PARAM[1] = CTABSSV(10, 1, $AC_PARAM[2])

Enable/cancel blocking

The following functions can be used to enable or cancel deletion and overwrite blocks for parts.

programs.

• Enable deletion and overwrite block.

General form: CTABLOCK(n, m, memType)

• Cancel deletion and overwrite block.

CTABUNLOCK releases the tables locked with CTABLOCK. Tables involved in an active

coupling remain locked, i.e. they cannot be deleted. However, the CTABLOCK command is

cancelled, i.e. the table can be deleted as soon as the coupling is deactivated. It is not

necessary to call CTABUNLOCK again.

General form: CTABUNLOCK(n, m, memType)

Applications of the forms:

Curve table with number n

CTABLOCK(n)

Curve tables in the number range n to m.

CTABLOCK(n, m)

All curve tables, irrespective of memory type

CTABLOCK()

All curve tables in the specified memory type

CTABLOCK(, , memType)

Curve table with number n

CTABUNLOCK(n)

Curve tables in the number range n to m.

CTABUNLOCK(n, m)

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All curve tables, irrespective of memory type

CTABUNLOCK()

All curve tables in the specified memory type

CTABUNLOCK(, , memType)

Other commands for calculating and differentiating between curve tables for applications for

diagnosing and optimizing the use of resources:

•

Number of defined tables irrespective of memory type

CTABNO()

•

Number of defined tables in SRAM or DRAM of NC memory

CTABNOMEM(memType)

•

Number of possible curve tables in memory memType.

CTABFNO(memType)

•

Table number of nth curve table.

General form: CTABID(n, memType)

Generates the table number of the nth curve table with memory type memType. CTABID(1,

memType) is used to read out the highest curve number (105) of the memory type specified.

CTABID(n)

Generates the table number of the nth curve table in the memory specified using the

following machine data:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE (default memory type for curve tables)

CTABID(p)

Generates the ID (table number) of the curve table entered in the memory as the pth curve

table.

Note

If for example, the sequence is changed between consecutive calls of CTABID(),

then CTABID(n, ...) can be used to provide a different curve table than the one provided

before the change.

•

Indicates the block state of curve table number n.

CTABISLOCK(n)

•

Checks curve table number n.

CTABEXISTS(n)

•

Returns the memory in which curve table number n is stored.

CTABMEMTYP(n)

•

Returns the table periodicity.

CTABPERIOD(n)

•

Number of curve segments already used in memory memType.

CTABSEG(memType, segType)

•

Number of curve segments used in curve table number n

CTABSEGID(n, segType)

•

Number of still possible curve segments in memory memType.

CTABFSEG(memType, segType)

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• Maximum number of possible curve segments in memory memType.

CTABMSEG(memType, segType)

• Number of polynomials already used in memory memType.

CTABPOL(memType)

• Number of curve polynomials used by curve table number n.

CTABPOLID(n)

• Number of still possible polynomials in memory memType.

CTABFPOL(n)

• Maximum number of possible polynomials in memory memType.

CTABMPOL(n)

Boundary values of curve tables

Behavior of the leading axis/following axes on the edges of the curve table:

• The value at the beginning of the curve table is read by a following axis.

CTABTSV(n, degrees, F axis), following value at the beginning of the curve table

• The value at the end of the curve table is read by a following axis.

CTABTEV(n, degrees, F axis), following value at the end of the curve table

• The value at the beginning of the curve table is read by the leading axis.

CTABTSP(n, degrees, F axis), master value at the beginning of the curve table

• The value at the end of the curve table is read by the leading axis.

CTABTEP(n, degrees, F axis), master value at the end of the curve table

• Determine the value range of the following value.

CTABTMIN(n, F axis), minimum following value of curve table

CTABTMAX(n, F axis), maximum following value of the curve table

Parameter

• Following axis:

Name of axis via which the following axis is programmed in the definition.

• Leading axis:

Name of axis via which the leading axis is programmed.

• n, m

Numbers for curve tables.

Curve table numbers can be freely assigned. They are used exclusively to uniquely identify a

curve table.

In order to delete a curve table area using the command CTABDEL(n, m) must be greater

than n.

• p

Entry location (in memType memory area)

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•

applim:

Behavior at the curve table edges.

0 non-periodic (table is processed only once, even for rotary axes).

–

1 periodic, modulo (the modulo value corresponds to the LA table values).

–

2 periodic, modulo (LA and FA are periodic).

•

Master value

Position value for which a following value is to be determined.

•

Slave value

Position value for which a master value is to be calculated.

•

aproxmastervalue

Position value that can be used to determine a unique master value in the case of an

ambiguous reversing function of the curve table.

•

degrees

Parameter in which the pitch of the table function is returned.

•

memType

Optional parameter for specifying memory type to be used n curve tables.

Possible values:

"SRAM" curve table is created in static NC memory.

"DSRAM" curve table is created in dynamic NC memory.

If an invalid type is entered, the value -2 is returned.

If the parameter is omitted, then the memory type set via the following machine data takes

effect:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE (default memory type for curve tables)

•

segType

Optional parameter for entry of segment type

Possible values:

segType "L" linear segments

segType "P" Polynomial segments

Further information: NC Programming Programming Manual

Restrictions

The following restrictions apply when programming:

• It is not permissible that the NC block generates a preprocessing stop.

• No discontinuities may occur in leading axis motion.

• Any block that contains a traverse instruction for the following axis must also include a

traverse for the leading axis.

• The direction of motion of the leading axis must not reverse at any point in the rule of motion,

i.e. the position of the leading axis must always be unique within the sequence of motions.

The programmed contour may not move perpendicular to the leading axis.

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• Axis names from gantry axis groups cannot be used to define a table (only leading axis are

possible).

• Depending on the following machine data, jumps in the following axis may be tolerated if a

movement is missing in the leading axis:

MD20900 $MC_CTAB_ENABLE_NO_LEADMOTION (curve tables with discontinuity of the

following axis)

The other restrictions listed above still apply.

Axis assignment

Does not take effect until coupling is activated with curve table.

Note

The dynamic limit values of the motion commands for a curve table are not checked until

activation or interpolation.

Starting value

The first motion command in the definition of a curve table defines the starting value for the

leading and following value.

All instructions that cause a preprocessing stop must be hidden.

Example 1

Without tool radius compensation, without memory type

Program code

Comment

N100 CTABDEF(AX2, AX1, 3.0)

; Start of the definition for the non-

; periodic curve table no. 3

N110 AX1=0 AX2=0

; 1st motion instruction specifies the start value

; leading value: 0, Following value: 0

N110 AX1=20 AX2=0

; 1st curve segment: Master value: 0...20,

; following value: Starting value …0

N120 AX1=100 AX2=6

; 2nd curve segment: Master value: 20...100,

; following value: 0...6

N130 AX1=150 AX2=6

; 3rd curve segment: Master value: 100...150,

; following value 6

N130 AX1=180 AX2=0

; 4th curve segment: Master value: 150...180,

; following value: 6...0

N200 CTABEND

; end of the definition, the curve table

; is generated in its internal representation.

; the advance is reorganized to the status

; at the start of N100

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Example 2

Example of a curve table with active tool radius compensation:

Prior to definition of a curve table with CTABDEF(), tool radius compensation must not be active;

otherwise alarm 10942 is generated. This means that tool radius compensation must be

activated within the definition of the curve table. Similarly, it must be deactivated again before

the end of the curve table definition, using CTABEND.

Program code

Comment

N10 CTABDEF(Y, X, 1, 0)

; Start of the definition for the non-

; periodic curve table no. 1

N20 X0 Y0

N30 G41 X10 Y0

; Tool radius compensation on

N40 X20 Y20

N50 X40 Y0

N60 X60 Y20

N70 X80 Y0

N80 G40 X90 Y0

; Tool radius compensation off

N90 CTABEND

Tool radius compensation is activated in block N30; this causes the approach movement for

radius compensation to be made in this block. Similarly, the approach movement for

deactivation of the radius compensation is made in block N80.

Note

The value pairs between CTABDEF and CTABEND must be specified for precisely the axis names

that have been programmed in CTABDEF as the leading axis name and following axis name. In

the case of programming errors, alarms or incorrect contours may be generated.

14.2.6

Access to table positions and table segments

Reading table positions

With the program commands CTAB and CTABINV the following value for a master value (CTAB)

can be read from the part program and from synchronized actions, or alternatively the master

value can be read off for a following value. The pitch value can be used to calculate the speed of

the following axis or leading axis at any position in the table.

Reading segment positions

Segment positions of a curve table for the value for the following axis can be read using the

CTABSSV and CTABSEV calls.

The language commands CTABSSV and CTABSEV generally provide the start and end values of

the internal segments of the curve tables for the following axis. These values only agree with the

programmed values of the curve tables if the programmed segments can be converted 1:1 to the

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internal segments of the curve table. This is always the case if only G1 blocks or axis polynomials

are used to define the curve tables and no other functions are active.

Under the following conditions, the programmed segments may not be converted unchanged

into the internal segments of the curve table:

• Circles or involutes are programmed

• Chamfering or rounding (CHF, RND) is active

• Smoothing with G643 is active

• Compressor function (COMP...) is active

• Tool radius compensation is active for polynomial interpolation

In these cases, the language commands CTABSSV and CTABSEV may not be used to query the

start and end points of the programmed segments.

CTABINV

When using the inversion function for the curve tables CTABINV, it must be noted that the

following value mapped to the leading value may not be unique.

Within a curve table, the following value can assume the same value for any number of master

value positions. In order to resolve this ambiguity, the program command CTABINV requires a

further parameter, in addition to the following value, which it uses to select the 'correct' master

value. CTABINV always returns the master value that is closest to this auxiliary parameter. This

auxiliary value can, for example, be the master value from the previous interpolator clock cycle.

Note

Although the auxiliary parameter permits calculation of a unique result for the reversal function

of the curve table, it should be noted that numerical inaccuracies may give rise to contours,

which can cause the reversal function to produce results that deviate from those that would be

obtained in a calculation where the accuracy is unrestricted.

Optional parameters

The functions CTAB, CTABINV, CTABSSV and CTABSEV have optional parameters for the leading

and following axes. If one of these parameters is programmed, the master value and following

value are modified using the scaling factors of the relevant axes.

This is particularly important if axes have been configured with different length units (inch/

metric). If no optional parameters are programmed, the master value and following value are

treated as path positions in the conversion from external to internal representation. This means

that the values are multiplied according to the configured resolution (decimal places) and the

remaining decimal places are truncated.

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Identifying the segment associated with master value X

Example of reading the segment starting and end values for determining the curve segment

associated with master value X = 30 using CTABSSV and CTABSEV:

Program code

Comment

N10 DEF REAL STARTPOS

; Beginning of the definition for the

start position of the curve table

N20 DEF REAL ENDPOS

N30 DEF REAL GRADIENT

N100 CTABDEF(Y,X,1,0)

; Start of table definition

N110 X0 Y0

; Start position, 1st table segment

N120 X20 Y10

; End position, 1st table segment =

; Start position 2nd table segment

N130 X40 Y40

N140 X60 Y10

; 3rd curve segment

N150 X80 Y0

; 4th curve segment

N160 CTABEND

; End of table definition

N200 STARTPOS=CTABSSV(30.0,1,GRADIENT)

; Start position Y in segment 2 = 10.

N210 ENDPOS=

; End position Y in segment 2 = 40

CTABSEV(30.0,1,GRADIENT)

; Segment 2 belongs to LW X = 30.0

&OE

4UBSU

Figure 14-2

Determining the curve segment associated with master value X = 30

Reading values at start and end

The values of the following axes and of the master axis at the start and end of a curve table can

be read with the following calls:

R10 =CTABTSV(n, degrees, F axis, following value at the beginning of the table)

R10 =CTABTEV(n, degrees, F axis, following value at the end of the table)

R10 =CTABTSP(n, degrees, L axis, master value at the beginning of the table)

R10 =CTABTEP(n, degrees, L axis, master value at the end of the table)

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Value range of the following value

The following example illustrates how the minimum and maximum values of the table are

determined using CTABTMIN and CTABTMAX:

Program code

Comment

N10 DEF REAL STARTVAL

; Beginning of the definition for the start

and initial values of the curve table

N20 DEF REAL ENDVAL

N30 DEF REAL STARTPARA

N40 DEF REAL ENDPARA

N50 DEF REAL U_MINVAL

N60 DEF REAL U_MAXVAL

N70 DEF REAL GRADIENT

…

N100

CTABDEF(Y,X,1,0)

; Start of table definition

N110

X0 Y10

; Start value, 1st table segment

N120

X30 Y40

; End position, 1st table segment =

; Start position 2nd table segment

N130

X60 Y5

; End position, 2nd table segment …

N140

X70 Y30

; End position, 3rd curve segment …

N150

X80 Y20

; End position, 4th curve segment …

N160

CTABEND

; End of table definition

N200

STARTPOS=CTABTSV(1,GRADIENT)

; STARTPOS = 10

; Start position of table as well as

N210

ENDPOS=CTABTEV(1,GRADIENT)

; ENDPOS = 20

; End position of table

N220

STARTPARA=CTABTSP(1,GRADIENT)

; STARTPARA = 0

; Master value at beginning of curve table

N230

ENDPARA=CTABTEP(1,GRADIENT)

; ENDPARA = 80

; Read master value at the end of the curve

table from the value range of the following

axis

N240

U_MINVAL=CTABTMIN(1)

; Minimum value when Y = 5 and

N250

U_MAXVAL=CTABTMAX(1)

; Maximum value when Y = 40

.BYJNVN

WBMVF

'JOBM WBMVF

4UBSU WBMVF

.JOJNVN

WBMVF

Figure 14-3

Determining the minimum and maximum values of the table

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14.2 Curve tables

14.2.7

Activation/deactivation

Activation

The coupling of real axes to a curve table is activated through this command:

LEADON (<Following axis>, <Leading axis>, <n>)

with <n> =Number of the curve table

Activation is possible:

• In the part program

• in the definition of a synchronous action

Example:

N1000 LEADON(A,X,3)

; Axis A follows the master value X according to the rule

of motions defined in Curve Table No. 3

Deactivation

The switch off of the coupling to a curve table takes place through the following command:

LEADON (<Following axis>, <Leading axis>)

Deactivation is possible:

• In the part program

• in synchronized actions

Note

While programming LEADOF, the abbreviated form is also possible without specification of

the leading axis.

Example:

N1010 LEADOF(A,X)

; The coupling of Axis A with its leading axis is canceled

Multiple use

A curve table can be used several times in a single part program to couple different channel axes.

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14.2 Curve tables

14.2.8

Modulo-leading axis special case

Position is absolute

When an axial master value coupling is active, the position of the following axis via a curve table

is unique, i.e. an absolute assignment to the master axis exists.

This means that, when a modulo rotary axis is used as the master axis, the position of the master

axis is absolute. In other words, the position of the modulo rotary axis entered in the curve table

is absolute, and not modulo-reduced.

Example

Let the position of a modulo rotary axis with LEADON be 210°. The position 210° degrees is used

as the starting value in the curve table. After one rotation of the modulo axis, the axis position

is again displayed as 210°. The absolute position 570° is however taken as the input value in the

curve table:

210° + 1 round (360°) = 570°

14.2.9

Behavior in AUTOMATIC, MDA and JOG modes

Activation

An activated curve table is functional in the AUTOMATIC, MDA and JOG modes.

Basic setting after run-up

No curve tables are active after run-up.

14.2.10

Effectiveness of PLC interface signals

Dependent following axis

With respect to the motion of a following axis that is dependent on the leading axis, only the

following axis interface signals that effect termination of the motion (e.g. axis-specific feed stop,

axis inhibit, servo enable, etc.) are effective.

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14.2 Curve tables

Leading axis

In an activated axis group, the interface signals move the leading axis through the axis coupling

to the associated following axis, i.e.:

• feed control of the leading axis causes a corresponding feed control of the following axis.

• A shutdown of the leading axis through interface signals (e.g., axis-specific feed stop, axis

inhibit, servo enable etc.) causes the corresponding following axis to shut down.

The effect of the axis inhibit of the leading axis on the following axis can be prevented through

the following MD setting:

MD37160 $MA_LEAD_FUNCTION_MASK, Bit 1 = 1

Position measuring system 1/2 (DB31, ... DBX1.5/1.6))

Switch-over of the position measuring system for the leading and following axes is not inhibited

for an active coupled axis group. The coupling is not canceled.

Recommendation: Switch the measuring system over when the coupling is deactivated.

14.2.11

Diagnosing and optimizing utilization of resources

The following functions allow parts programs to get information on the current utilization of

curve tables, table segments and polynomials.

One result of the diagnostic functions is that resources still available can be used dynamically

with the functions, without necessarily having to increase memory usage. The description of the

parameters in Chapter "Programming Curve Tables" also applies to the following functions.

a) Curve tables

• Determine total number of defined tables.

The definition applies to all memory types (see also CTABNOMEM)

CTABNO()

• Number of defined tables in SRAM or DRAM of NC memory.

CTABNOMEM (memType)

If memType is not specified, the memory type specified in the following machine data:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE (default memory type for curve tables)

Result:

>= 0: Number of defined curve tables

-2: Invalid memory type

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14.2 Curve tables

• Determine number of curve tables still possible in memory.

CTABFNO(memType)

If memType is not specified, the memory type specified in the following machine data:

MD220905 $MC_CTAB_DEFAULT_MEMORY_TYPE

Result:

>= 0: Number of possible tables

-2: Invalid memory type

• Determine the table number of the pth table in the memory type specified optionally

CTABID(p, memType)

If memType is not specified, the memory type specified in the following machine data:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE

Result:

Table number or

Alarm for invalid p or memType

When using the CTABID(p, memType) function, no assumptions should be made regarding

the sequence of the curve tables in the memory. The CTABID(p, ...) function supplies the

ID (table number) of the curve table entered in memory as the pth curve table.

If the sequence of curve tables in memory changes between consecutive calls of

CTABID()CTABID(), e.g. due to the deletion of curve tables with CTABDEL(), the

CTABID(p, ...) function can supply a different curve table with the same number.

To prevent this from happening, the curve tables concerned can be locked, using the

CTABLOCK(...) language command. In this case, it should be noted that the curve tables

concerned are then unlocked with CTABUNLOCK().

•

Determine block condition

Table n

CTABISLOCK(n)

Result:

> 0: Table is blocked

Reason for block:

1: by CTABLOCK()

2: by an active coupling

3: by CTABLOCK()and by an active coupling

= 0: Table is not blocked

- 1: Table does not exist

• Check whether the curve table exists

CTABEXISTS(n)

Result:

1: Table exists

0: Table does not exist

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14.2 Curve tables

•

Determine memory type of a curve table

CTABMEMTYP(n)

Result:

0: Table in static SRAM NC memory

1: Table in dynamic "DRAM" NC memory

-1: Table does not exist

• by an active coupling periodic

CTABPERIOD(n)

Result:

0: Table is not periodic

1: Table is periodic in the leading axis

2: Table is periodic in the leading and following axes

-1: Table does not exist

b) Curve table segments

•

Determine number of used curve segments of the type memType in the memory range.

•

CTABSEG(memType, segType)

•

If memType is not specified, the memory type specified in the following machine data:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE

Result:

>= 0: Number of curve segments

-2: Invalid memory type

If segType is not specified, the sum is produced via linear and polynomisl segments in the

memory type.

-2: segType not equal "L" or "P"

•

Determine number of used curve segments of the type memType in the memory range

CTABSEGID(n, segType)

Result:

>= 0: Number of curve segments

-1: Curve table with number n does not exist

-2: segType not equal "L" or "P"

•

Determine number of free curve segments of the type memType in the memory range

CTABFSEG(memType, segType)

If memType is not specified, the memory type specified in the following machine data:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE

Result:

>= 0: Number of free curve segments

-2: Invalid memory type, segType not equal "L" or "P"

•

Determine maximum number of possible curve segments of the type segType in the memory

CTABMSEG(memType, segType)

If memType is not specified, the memory type specified in the following machine data:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE

Result:

>= 0: Maximum number of possible curve segments

-2: Invalid memory type, segType not equal "L" or "P"

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14.2 Curve tables

c) Polynomials

• Determine the number of used polynomials of the memory type

CTABPOL(memType)

If memType is not specified, the memory type specified in the following machine data:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE

Result:

>= 0: Number of polynomials already used in the memory type

-2: Invalid memory type

• Determine the number of curve polynomials used by a curve table

CTABPOLID(n)

Result:

>=0: Number of used curve polynomials

-1: Curve table with number n does not exist

• Determine the number of free polynomials of the memory type

CTABFPOL(memType)

If memType is not specified, the memory type specified in the following machine data:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE

Result:

>= 0: Number of free curve polynomials

-2: Invalid memory type

• Determine the maximum number of polynomials of the memory type

CTABMPOL(memType)

If memType is not specified, the memory type specified in the following machine data:

MD20905 $MC_CTAB_DEFAULT_MEMORY_TYPE

Result:

>= 0: Maximum number of possible curve polynomials

-2: Invalid memory type

14.2.12

Supplementary conditions

Transformations

Transformations are not permissible in curve tables. TRAANG is an exception.

TRAANG

If TRAANG is programmed, the rule of motion programmed in the basic co-ordinate system is

transformed to the associated machine co-ordinate system. In this way it is possible to program

a curve table as Cartesian co-ordinates for a machine with inclined linear axes.

The condition that stipulates that "the direction of motion of the leading axis must not reverse

at any point of the rule of motion" must then be met in the machine co-ordinate system. Please

note that this condition in the basic co-ordinate system does not have the same meaning as in

the machine co-ordinate system, since the contour tangents are changed by the transformation.

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14.2 Curve tables

14.2.13

Examples

Definition of a curve table with linear sets

%_N_TAB_1_NOTPERI_MPF

;$PATH=/_N_WKS_DIR/_N_KURVENTABELLEN_WPD

; Def.TAB1 0-100mm Kue1/1 notperio.

N10 CTABDEF(YGEO,XGEO,1,0)

; FA=Y LA=X Curve No..=1 Not

period.

N1000 XGEO=0 YGEO=0

; Start values

N1010 XGEO=100 YGEO=100

CTABEND

M30

Definition of a curve table with polynomial sets

%_N_TAB_1_NOTPERI_MPF

;$PATH=/_N_WKS_DIR/_N_KURVENTABELLEN_WPD

; Def.TAB1 0-100mm Kue1/1 notperio.

N10 CTABDEF(Y,X,1,0)

; FA=Y LA=X Curve

No..=1 Not period.

N16 G1 X0.000 Y0.000

N17 POLY PO[X]=(31.734,0.352,-0.412) PO[Y]=(3.200,2.383,0.401)

N18 PO[X]=(49.711,-0.297,0.169) PO[Y]=(7.457,1.202,-0.643)

N19 PO[X]=(105.941,1.961,-0.938) PO[Y]=(11.708,-6.820,-1.718)

N20 PO[X]=(132.644,-0.196,-0.053) PO[Y]=(6.815,-2.743,0.724)

N21 PO[X]=(147.754,-0.116,0.103) PO[Y]=(3.359,-0.188,0.277)

N22 PO[X]=(174.441,0.578,-0.206) PO[Y]=(0.123,1.925,0.188)

N23 PO[X]=(185.598,-0.007,0.005) PO[Y]=(-0.123,0.430,-0.287)

N24 PO[X]=(212.285,0.040,-0.206) PO[Y]=(-3.362,-2.491,0.190)

N25 PO[X]=(227.395,-0.193,0.103) PO[Y]=(-6.818,-0.641,0.276)

N26 PO[X]=(254.098,0.355,-0.053) PO[Y]=(-11.710,0.573,0.723)

N27 PO[X]=(310.324,0.852,-0.937) PO[Y]=(-7.454,11.975,-1.720)

N28 PO[X]=(328.299,-0.209,0.169) PO[Y]=(-3.197,0.726,-0.643)

N29 PO[X]=(360.031,0.885,-0.413) PO[Y]=(0.000,-3.588,0.403)

CTABEND

N30 M30

Definition of a periodic curve table

Table No: 2

Master value range: 0 - 360

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14.3 Master value coupling

The following axis traverses from N70 to N90, a movement from 0 to 45 and back to 0.

N10 DEF REAL DEPPOS

N20 DEF REAL GRADIENT

N30 CTABDEF(Y,X,2,1)

N40 G1 X=0 Y=0

N50 POLY

N60 PO[X]=(45.0)

N70 PO[X]=(90.0) PO[Y]=(45.0,135.0,-90)

N80 PO[X]=(270.0)

N90 PO[X]=(315.0) PO[Y]=(0.0,-135.0,90)

N100 PO[X]=(360.0)

N110 CTABEND

N130 G1 F1000 X0

; Testing the curve by coupling Y to X

N140 LEADON(Y,X,2)

N150 X360

N160 X0

N170 LEADOF(Y,X)

N180 DEPPOS = CTAB(75.0,2,GRADIENT)

; Reading the table position at master

value 75.0 from the curve table with

Table No. 2

N190 G0 X75 Y=DEPPOS

; Positions of leading and following

axis

N200 LEADON(Y,X,2)

; No synchronization of the following

axis is required after the coupling

is activated

N210 G1 X110 F1000

N220 LEADOF(Y,X)

N230 M30

14.3

Master value coupling

14.3.1

Product brief

14.3.1.1

Function

The "axial master value coupling" function can be used to process short programs cyclically with

close coupling of the axes to one another and a master value that is either generated internally

or input from an external source.

The master value can, for example, be derived from a conveyor belt or a vertical shaft.

The axial master value coupling can be switched on and off in the NC part program or via

synchronized action.

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14.3 Master value coupling

14.3.1.2

Preconditions

The option "Master Value Coupling and Curve Tables Interpolation" or the relevant option of

generic coupling (refer to " Preconditions (Page 609) " in the "Brief description" for generic

coupling) is a prerequisite for utilization of the function.

14.3.2

General functionality

Curve table

With the axial master value coupling, a leading and a following axis are moved in synchronism.

It is possible to assign the position of the following axis via a curve table or the resulting

polynomial uniquely to a position of the leading axis - simulated if necessary.

Master value object

The master value object is the input variable for the curve table.

The following can be defined as the position of the master value object:

• The axis actual position (actual value measured by transmitter)

• The setpoint position (calculated from interpolator) (default)

If the leading axis is interpolated by the same NCU, the setpoint coupling delivers a better follow-

up response than is possible for actual value coupling (in the same IPO cycle).

Virtual leading axis / simulated master value

If the leading axis is not interpolated by the same NCU, the interpolator that is implemented in

the NCU for this particular leading axis can be used for master value simulation. The following

machine data settings must be defined for this:

MD30132 $MA_IS_VIRTUAL_AX[n] = 1 (axis is virtual axis)

MD30130 $MA_CTRLOUT_TYPE[n] = 0 (simulation as output type of setpoint)

Properties of master value simulation:

• Separation of IPO and servo.

• Actual values of the axis are recorded.

• Setpoint values are produced by IPO but not passed on to the servo motor.

• When switching over to master value coupling, the simulation can be programmed with the

last actual value read, whereas the path of the actual value is generally outside the control

of the NCU.

• If, for purposes of master value simulation, the master value object is switched from actual

value coupling to setpoint value coupling and a traversing command is issued for the leading

axis in the same interpolator clock cycle, the interpolator for the axis is initialized by the NC

so that the master value produces a constant path in the first derivation.

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14.3 Master value coupling

Note

Virtual axes assigned to a real drive must remain unblocked.

Offset and scaling

The setpoint value for the following axis can be offset and scaled. The following setting data is

used for this:

SD43102 $SA_LEAD_OFFSET_IN_POS (offset of master value with coupling to this axis)

SD43104 $SA_LEAD_SCALE_IN_POS (scaling of master value with coupling to this axis)

SD43106 $SA_LEAD_OFFSET_OUT_POS (offset of function value of the curve table)

SD43108 $SA_LEAD_SCALE_OUT_POS (scaling of function value of the curve table)

If (x) is a periodic curve table and this is interpreted as oscillation, the offset and scaling can also

be interpreted as follows:

SD43102 $SA_LEAD_OFFSET_IN_POS[Y] offsets the phase of the oscillation.

SD43106 $SA_LEAD_SCALE_OUT_POS[Y] affects the amplitude.

SD43108 $SA_LEAD_OFFSET_OUT_POS[Y] offsets the center of the oscillation

If the coupling is activated and synchronous, the new set position is approached as soon as

values are written to this setting data.

4"@-&"%@4$"-&@*/@104<'">

4"@-&"%@4$"-&@065@104<'">

5IF JOQVU WBMVF JT NVMUJQMJFE

5IF PVUQVU WBMVF JT NVMUJQMJFE

4FUUJOH EBUB JT F꫻FDUJWF PVUTJEF PG UIF UBCMF EF꫼OJUJPO BMTP JO

UIF OFHBUJWF EJSFDUJPO

JO NN

8JUI */ 4$

"-& IBT OP

8JUI 065

4$"-& IBT

F꫻FDU PVUTJEF PG UIF 5"#

JO NN

5BCMF EF꫼OJUJPO GPS FYBNQMF

࢕

$5"#%&' '" -" $5"#/3

-" '"

࢕

$5"#&/%

Figure 14-4

Master value coupling offset and scaling (multiplied)

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14.3 Master value coupling

4"@-&"%@0''4&5@*/@104<'">

4"@-&"%@0''4&5@065@104<'">

5IF DBMDVMBUFE QPTJUJPO PG UIF MFBEJOH BYJT JT P꫻TFU XJUI UIF

5IF DBMDVMBUFE QPTJUJPO PG UIF GPMMPXJOH BYJT JT P꫻TFU XJUI UIF

TQFDJ꫼FE JODSFNFOUT

*G UIF 5"# JT NPWFE PVUTJEF PG UIF '" -&"%0/ QPTJUJPO -"%

DBOOPU CF TXJUDIFE PO 4FUUJOH EBUB JT F꫻FDUJWF PVUTJEF PG UIF

UBCMF EF꫼OJUJPO BMTP JO UIF OFHBUJWF EJSFDUJPO

/FX -" XJUI

JO NN

࢕

8JUI */ 0''

4&5 IBT

8JUI 065 0''4&5 IBT

F꫻FDU PVUTJEF PG UIF 5"#

࢕

JO NN

Figure 14-5

Master value coupling offset and scaling (with increment offset)

Reaction to Stop

All leading value coupled following axes react to channel stop and MODE GROUP stop.

Master value coupled following axes react to a stop due to end of program (M30, M02) if they

have not been activated by static synchronized actions (IDS=...). The following machine data

is to be observed in this connection:

MD20110 $MC_RESET_MODE_MASK (definition of initial control settings after RESET / TP End)

MD20112 $MC_START_MODE_MASK (definition of initial control settings for NC-START)

Leading axis and following axis must always interpolate in the same channel. A following axis

located in a different channel cannot be coupled (axis replacement).

START and mode change enable a following axis in the master value coupling that has been

stopped.

RESET also enables a stopped following axis in master value coupling. If enabling by RESET is not

desired, or if it is dangerous (e.g. because the following axis is coupled to an external master

value not controlled by the NC), then MD20110 must be programmed such that master value

couplings are switched off with RESET (=2001H, i.e. bit 13 set to 1).

Axial functions

Actual value coupling causes a position offset between the leading and following axis. The cause

of this is the IPO cycle-based dead time in the position controller, which lies between the actual

value of the leading axis and the following axis.

Normally, the position offset and the following error is compensated by a linear extrapolation of

the master value to the extent of this dead time, i.e. dead time compensation is active in master

value coupling. The following MD setting is defined to deactivate the dead time compensation:

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SINUMERIK 840D sl. Service - Functions. Manual (2018-2020) - page 11