Difference between revisions of "SimpleMotion motion control strategies"

Send setpoint commands to a target drive with simple "write parameter" commands

• The easiest way to do point-to-point motion control
• Motion acceleration and velocity trajectories are produced by drive and can be set before motion is started
• Can modify any drive parameter on the fly
• Can be used together with other setpoint sources

• No multi-axis synchronization, all axes operate in point-to-point mode individually

List of positions are uploaded to drive command buffers and executed by drives based on clock

• Allow synchronizing multiple axes and running arbitrary motion paths
• Motion acceleration and velocity profiles are generated by user application
• Drives syncronize clocks so motion stays in sync infinitely
• Typical setpoint update rates are 250 Hz to 1000 Hz for 1 to 4 axis systems
• Use of Setpoint smoothingCIS smoothens any motion above 250 Hz to silky smooth

• Delay caused by buffering (0.1-1.0 sec buffering is recommended to avoid buffer underruns and stopping of motion)
• Can be complex to program
• Update rate will reduce as more axes are added to the system (due to bus bandwidth limit)

Position commands are sent to drives just like in parameter communication strategy, except in high update rate and from real-time host

• Allow synchronizing multiple axes and running arbitrary motion paths
• Motion acceleration and velocity profiles are generated by user application
• Use of Setpoint smoothingCIS smoothens any motion above 250 Hz to silky smooth
• There is virtually no delay between command and action

• Update rate will reduce as more axes are added to the system (due to bus bandwidth limit)
• For smooth unterrupted motion, need hard real-time host, such as RTLinux, PLC or microcontroller platform.
• USB RS458 converter may add uncertainty to timing, so use of other adapter may be necessary.