Configuration of a Slave Axis Group (Channels 21 to 24)
(Original Document)
About us
Introduction
A slave axis group is a collection of axes, composed of slave axes (a maximum of 6), which follow the movements of a master axis.
The master axis may be a real axis, an imaginary axis or an external setpoint. The slave axes are real or imaginary axes.
The rules to be observed for a TSX CSY 85 module using the new interpolation functions are as follows:
Configuration Screen
The configuration screen of a slave axis group appears below. It features 7 zones, which are used to configure the master axis and the 6 possible slave axes.
Master
This field is used to define the number of the master axis (1 to 16). The value N indicates that the master axis has not been chosen.
Slave Zones
The 6 slave zones (1 to 6) are identical. They are only active when the master number is defined.
Slave Zone Parameters
Description
Parameter
Description
Slave 1 (to 6)
Used to set the number of the slave axis (axes 1 to 12).
Measurement
When this button is checked, the slave axis follows the measured position of the master axis. This button operates alternately with the Setpoint button.
Setpoint
When this button is checked, the slave axis follows the position of the master axis setpoint. This button operates alternately with the Measurement button.
Gearing
When the button is checked, the slave axis follows the master axis in Ratio mode; that is to say following a ratio determined by the Ratio field. This button operates alternately with the Cam button.
Cam
When this button is checked, the slave axis follows the master axis in Cam mode; that is to say following the cam profile whose number is selected in the No. field. This button operates alternately with the Gearing button.
Ratio
In Ratio mode, these 2 fields are used to input the numerator and the denominator, which define the ratio between the master axis and the slave. These values are entered as floating points.
Start
Used to select the start condition:
  • Immediate
  • When the master position, increased by the offset value, reaches the threshold value defined in the Trigger field (CW travel)
  • When the master position plus the offset value, reaches the threshold value defined in the Trigger field (CCW direction)
  • When the master position plus the offset value is greater than or equal to the threshold value defined in the Trigger field
  • When the master position plus the offset value is less than or equal to the threshold value defined in the Trigger field
No.
In Cam mode, this field is used to select the cam profile number (between 25 and 31).
Offset
In Cam mode, this field is used to input an offset value, which will be added to the master position, in order to define the position of the slave.
The resulting position of the slave will be given by the index in the cam profile master table. This index is equal to the current position of the master + offset (for example, a cam profile defined from 0 to 1000 for the master coordinates). To start following a master position equal to 100000, the offset value should be equal to -100000.0.
This offset is used, for example, to define a sine and cosine function from the same cam profile. This value is entered as a floating point.
Bias remains (residual)
When this box is checked:
  • A dynamic offset is added automatically to the master position in order to define the position of the slave.
  • The additional slave movements are not halted when the link with the master is removed.
Trigger
When the start condition is dependent on the position of the master axis in relation to a threshold, this field is used to input the threshold value. This value is entered as a floating point.
Activation will take place when the current position of the master + offset > (or <, >, <) the value of the threshold (Trigger).
Stop on follow-on
When this box is checked, confirming the link between the master and the slave will stop any possible additional movement of the slave axis, following a deceleration profile determined automatically.
Stop master/flt
When this box is checked, the master stops when there is a contour discrepancy (fault) between the master and the slave.
Position of a Slave Axis
When an axis is a slave, its position depends solely on that of the master axis, which it is following. The configuration parameters of the axis (position limits, maximal speed, maximal acceleration, etc.) are ignored. To safeguard the application, configure these (security) parameters in the servodrive.
Scale Factor
In a group of slave axes, the scale factor is unrelated to the units used for the axes, when these are of the same type (Linear, Angular, etc.). For example, if the master axis is configured in m and the slave axe in cm (different units but the same type: Linear), and if a scale factor of 1/1 is used, this means that for every 1 mm traveled by the master, the slave will also move 1 mm.
If the master and slave units are of different types, the units must be converted into the reference unit of the type of unit (mm for the linear type, inch for the linear English type, rev for the angular type). For example, if the master is configured in m and the slave in revs (units of different types: Linear and Angular) the slave is to complete 1 revolution when the master moves 1 m, the scale factor will have to be defined as follows:
Therefore, the scale factor = 1000/1 (when the master travels 1000 mm, the slave completes 1 revolution).