12-06-2010 12:28 PM
I have four Zaber motors connected to a single driver. I was wondering if there was a way to send commands to two motors to execute simultaneously without any errors in the same VI.
12-07-2010 10:00 AM
Hello bilaln:
You are able to sychronize your motor movements by ensuring that the axes are defined as a part of the same vector space. You can also choose the multi-start feasture within the Start Motion VI. These steps are detailed in the following Knowledgebase article:
http://digital.ni.com/public.nsf/allkb/D0B76B3150083B39862571DB0064B1F6?OpenDocument
Best of luck!
12-14-2010 02:33 PM
Hi bilaln and Sarci1,
Although Zaber motors are stepper motors, most of them have integrated controllers, so you communicate with them using a serial port instead of step-and-direction pulses. That makes controlling them simpler, but some things like synchronizing multiple axes become harder. The simplest technique is to send a command to one device and then immediately send a command to the other device. There will be a delay of a few milliseconds between the two commands because of the time it takes to transmit a command over the serial port.
You can get closer to simultaneous commands by sending a command to device number zero. Both devices will receive the command at the same time, but there will still be a slight delay because their timing crystals are not synchronized with each other. Also, this only works if you want both devices to make the same move. You can get tricky by starting them both in the same direction and then immediately changing the target position of one of them.
yours,
Don Kirkby
Zaber Technologies