System Philosophy; Introduction - Omron TJ1-DRT Hardware Reference Manual

System philosophy

2 System philosophy
2.1

Introduction

The system philosophy is centred around the relationship between:
• System architecture
• Cycle time
• Program control and multi-tasking
• Motion sequence and axes
• Motion buffers
A clear understanding of the relationship between these concepts
is necessary to obtain the best results for the Trajexia system.
2.1.1 Glossary
Motion sequence
The Motion Sequence is responsible for controlling the position of
the axes.
Servo period
Defines the frequency at which the Motion Sequence is executed.
The servo period must be set according to the configuration of the
physical axes. The available settings are 0.5ms, 1ms or 2ms.
Cycle time
Is the time needed to execute one complete cycle of operations in
the TJ1-MC__. The cycle time is divided in 4 time slices of equal
time length, called "CPU Tasks". The cycle time is 1ms if
SERVO_PERIOD 0.5ms or 1ms and 2ms if the
SERVO_PERIOD=2ms.
HARDWARE REFERENCE MANUAL
AXIS CONTROL LOOP
TJ1-MC16
Buffer &
Buffer &
Position
Position
Program Buffer
profile
profile
Loop Loop
generator
gererator
TJ1-ML16
BASIC PROGRAMS
Process 1
Process 2
Process 3
...
Process 14
Co mms
TJ1 FL02
MC I/O
Ethernet
TJ1-PRT
FINS
Ethernet Profibus
Via
BUILT-IN TJ1-ML16
fig. 1
AXIS TYPE AXIS TYPE AXIS TYPE
Servo drive.
Position
Position Loop
Loop
Speed Loop
Speed Loop
Torque
Torque Loop
Loop
-
Servo drive.
Speed Loop
Torque Loop
ENC
All other
Servo
drives
MOTOR
ENC
MOTOR
14