User Manual
Chapter 1
GFK-1742F
Jan 2020
Product Overview
11
Figure 3: Simplified Standard Mode Position Loop with Velocity Feedforward (Analog
Velocity Interface)
Follower Mode Operation
Figure 4 is a simplified diagram of the Follower mode Position Loop. It is like the Standard
mode Position Loop (see previous page) with the addition of a Master Axis input. The Master
Axis input is an additional command source producing a Master Axis Position and Master
Axis Velocity. Master Axis Position is summed with Commanded Position from the axis
Command Generator. Master Axis Velocity is summed with the Commanded Velocity
(Velocity Feedforward) output of the axis Command Generator. Therefore, the
servomotor’s position and velocity
are determined by the sum of the Command Generator
output and Master Axis input. The Command Generator and Master Axis input can operate
simultaneously or independently to create Servo Axis motion.
The DSM314 allows several sources for the Master Axis input:
•
Axis 1 Commanded Position
•
Axis 1 Actual Position (Axis 1 Encoder)
•
Axis 2 Commanded Position
•
Axis 2 Actual Position (Axis 2 Encoder)
•
Axis 3 Commanded Position
•
Axis 3 Actual Position (Axis 3 Encoder)
•
Axis 4 Commanded Position
•
Axis 4 Actual Position (Axis 4 Encoder)
The ratio at which a Servo Axis follows the Master Axis is programmable as the ratio of two
integer numbers. For example, a Servo Axis can be programmed to move 125 Position
Feedback units for every 25 Master Axis Position units. Each time the Master Axis Position
changed by 1 position unit; the Servo Axis would move (125 / 25) = 5 Position Feedback
units.