I have been using a Dynamixel MKR Shield to control 12 XL330-M288 actuators. Is it possible to overload this board, e.g. by simultaneously moving all the actuators at max speed? While experimenting, I accidentally sent the wrong instructions, causing all the actuators to jump to extreme positions. After that, the shield no long seems to be detecting or communicating with any of the servos.
Unfortunately, a similar thing had happened to me too. An XL-330 had a short, and this power event had propagated to 2 other XL-330s and my OpenRB-150, destroying them all.
So FIRST, unhook everything, DXL MKR Shield and XL-330s. Then ideally, if you have a way to power each of the XL-330s one by one and then check each of them via a U2D2 and Dynamixel Wizard to see if any of them survived. Hopefully, they just need firmware recovery. Or can you check to see if you get proper Voltages at the VDD and GROUND pins on each of the 3-pin DXL connectors on the DXL MKR Shield without any actuator connected?
Do you have just ONE other WORKING actuator that you can use to test if the DXL MKR Shield is working any more? Or a back up DXL MKR Shield to use?
Hopefully, the Arduino Controller that you used with this DXL MKR Shield is still OK?
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Hey, thanks roboteer for your response. I don’t think I shorted anything, but maybe? Hope not. I’ve ordered a couple of extra shields, just in case, and I do have some other servos, but need to find a JST to Molex cable. I know I have one, but need to dig it out.
A follow up question is whether it would be wise to put some kind of current limiter between the power source and the MRK shield? How likely is it to burn out if 12 XL330’s are pushed to their limits? I mean, they’re not very powerful things.
Hmmh! Why do you need a JST to Molex cable, when you are only using XL-330s? Just regular X3P extension cables should work.
Are you daisy-chaining in series all your XL-330s? You could use these X3P hubs to parallelize your power and control circuits into groups of 4 or 3 XL-330s per “branch” out of the DXL MKR Shield - if your robot physical setup allows this procedure. That should help.
Come to think of it, I should use a current limiter on my robots too. Previously, when my XL-330 failed, it created a short so my XL-330 melted down at its DXL connector and also it was smoking!.
Also read this post, it has some other relevant discussions:
I have some older Dynamixels that use the Molex connectors.
30A sounds like there should be a lot of head-room, even for 12 servos.