Trajexia System Architecture; Hardware Reference Manual - Omron GRT1-ML2 Hardware Reference Manual

System philosophy
The output speed gain can be useful for smoothing motions but will
generate high Following Errors. The output speed gain axis parameter is
called OV_GAIN.
• Speed feed forward gain
The speed feedforward gain K
proportional to the change in demand position P
Following Error at high speed.
O = K · ∆P
vff vff d
The parameter can be set to minimise the Following Error at a constant
machine speed after other gains have been set. The speed feed forward
gain axis parameter is called VFF_GAIN.
The default settings are given in the table along with the resulting profiles.
Fractional values are allowed for gain settings.
/i
Gain
Proportional gain
Integral gain
Derivative gain
Output speed gain
Speed feedforward gain
2.4

Trajexia system architecture

The system architecture of the Trajexia is dependant upon these
concepts:
• Program control
• Motion Sequence
• Motion buffers
• Communication
• Peripherals
These concepts depend upon the value set in the SERVO_PERIOD
parameter. The relationship between the value of SERVO_PERIOD and the
different concepts of the system architecture are describes as follows.

HARDWARE REFERENCE MANUAL

produces an output O that is
vff vff
and minimizes the
d
Default value
0.1
0.0
0.0
0.0
0.0
2.4.1 Program control
Programs make the system work in a defined way. The programs are written
in a language similar to BASIC and control the application of the axes and
modules. 14 Programs can be executed in parallel. The programs can be set
to run at system power-up, started and stopped from other programs and
executed from Trajexia Tools.
Programs execute commands to move the axes, control inputs and outputs
and make communication via BASIC commands.
2.4.2 Motion sequence
The motion sequence controls the position of all 16 axes with the actions as
follows:
• Reading the Motion buffer
• Reading the current Measured Position (MPOS)
• Calculating the next Demanded Position (DPOS)
• Executing the Position loop
• Sending the Axis reference
• Error handling
2.4.3 Motion buffers
Motion buffers are the link between the BASIC commands and the Axis
control loop. When a BASIC motion command is executed, the command is
stored in one of the buffers. During the next motion sequence, the profile
generator executes the movement according to the information in the buffer.
When the movement is finished, the motion command is removed from the
buffer.
2.4.4 Communication
All communication is carried out in the forth CPU task. A set of BASIC
communication commands are used to configure the communications.
When the Trajexia is a communication slave (as in the PROFIBUS
communication) it is only necessary to configure the communication in an
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