Hi,
Is it possible to control 2 motors at once using the pololu serial 8 servo controller?
I am controlling them via matlab but have noticed that i need to insert a pause command (for around 0.3 seconds) bewteen sending position commands
(in pololu mode) otherwise the motors do not respond accurately or correctly. It seems that the message is not correctly recieved.
Is there a way to send it a command to move both motors at the same time via matlab?
Cheers
Hello.
There aren’t any specific commands for simultaneous commands to multiple channels, but just sending commands back to back will result in the motors moving practically simultaneously. If your back to back commands are causing weird behavior, you’re probably not sending them correctly. In what sense are the servos not responding “accurately or correctly”?
- Jan
Hello.
The behavior you’re describing could also be the result of insufficient power (if both servos start straining simultaneously, they draw more power than if they move one after the other). What is your power source?
- Ben
Sorry for the late reply. Thanks for your input.
I am using a power supply (although i am using the same supply to power the servo’s and the servo controller).
The servo’s do not strain with the commands, it just seems that when i send one command after the other
(without a pause) its as if the message is not recieved correctly. If i remember correctly the red (?) LED flashes
to indicate that the message was out of range etc. and the servo’s do not move to their correct positions.
If i insert a suitable pause though i do not get this problem (i think it was a pause of around .3 seconds, anything less
and the problem would occur).
This is all using a baud rate of 9600. Could this be the problem? if so does it matter what baud rate i choose and what
would you recommend?
I will test this out again to let you know precisely what they are doing wrong.
Cheers
The baud rate shouldn’t matter, other than limiting your maximum rate of commands. I think your problem is going to be with how you’re sending commands to the controller, and there isn’t much I can help with that. It’s difficult enough to troubleshoot other people’s problems without going off of recollections of what might have happened, so I don’t think you’ll get much more of a response until you can describe what’s going on with more confidence. By the way, no need to apologize for late replies: it’s not as if we’re waiting on pins and needles for your updates. However, if you do figure out what your problem is, we’d appreciate your posting about it in case it helps others in the future.
- Jan
