Omron TJ1/GRT1 Hardware Reference Manual page 25

System philosophy
2.3.2 Internal operation of the TJ1-MC__
Inferred closed loop systems occupy the mainstream in modern servo
systems applied to positioning devices for industrial applications. The figure
shows the basic principle of the servo system as used in the TJ1-MC__.
1. The TJ1-MC__ performs actual position control. The main input of the
controller is the Following Error, which is the calculated difference
between the demand position and the actual measured position.
2. The Position Controller calculates the required speed reference output
determined by the Following Error and possibly the demanded position
and the measured position. The speed reference is provided to the
Servo Driver.
3. The Servo Driver controls the rotational speed of the servo motor
corresponding to the speed reference. The rotational speed is
proportional to the speed reference.
4. The rotary encoder generates the feedback pulses for both the speed
feedback within the Servo Driver speed loop and the position feedback
within the TJ1-MC__ position loop.
The labels in the figure are:
A. TJ1-MC__.
B. Servo system.
C. Demand position.
D. Position control.
E. Speed reference.
F. Speed control.
G. Motor.
H. Encoder.
I. Measured speed.
J. Measured position.
2.3.3 Motion control algorithm
The servo system controls the motor by continuously adjusting the speed
reference to the Servo Driver. The speed reference is calculated by the
motion control algorithm of the TJ1-MC__, which is explained in this section.
HARDWARE REFERENCE MANUAL
fig. 15
A
2
3
C E
1
D F
J
B
G
4
I
H
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