System philosophy
HARDWARE REFERENCE MANUAL
8
Revision 5.0
2
System philosophy
2.1
Introduction
fig. 1
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 0.25ms, 0.5ms, 1ms or 2ms.
Cycle time
Is the time needed to execute one complete cycle of operations in the
TJ2-MC__. The cycle time is divided in 4 time slices of equal time length,
called "CPU slots". The cycle time is 1ms if
SERVO_PERIOD
=0.25ms,
0.5ms or 1ms and 2ms if the
SERVO_PERIOD
=2ms.
AXIS TYPE
AXIS TYPE
MOTION SEQUENCE
Position
Loop
Servo Drive
MOTOR
Speed Loop
Torque
Loop
Loop
Servo Drive
MOTOR
ENC
Speed Loop
Position
Loop
Torque
Loop
ENC
Speed Loop
Torque
Loop
Program Buffer
BASIC PROGRAMS
Process 0
Process 1
Process 2
…
Process 21
Comms
TJ2-MC64
AXIS TYPE
Ethernet
FINS
Ethernet
MC I/O
Profibus
DeviceNET
CANopen
Built-in
Via TJ1-ML__ / TJ2-ECT__
PLC TASKS
TJ1-PRT/DRT/CORT
TJ1-ML__
TJ2-ECT__
TJ1-FL02
All other
Servo
Drives
Buffer &
profile
gererator
Position
Loop