Hi, I'm trying to connect 4 vesc controllers over the can-bus interface and run them synchronous. I have removed the resistor on the two vescs in the middle, leaving the first and fourth with a resistor. But the issue is that the motors are not running very well, they are stuttering and locking up.
I have tried and successfully runned two and two, but not 3 and 4 together.
For me it seems like there is a communication problem when running more than two vesc controllers over can-bus. Has anyone successfully gotten 4 vesc to run synchronous?
I'm using the standard single vesc from trampa boards.
Thanks
Did you only connect CAN H and CAN L? No other interconnections in between the 4 Units?
Yes, only CAN H and CAN L
Here is a picture of the setup:
Thanks
Are they in current control mode? You could try the setup with all wheels in the air. 4 wheels down on the ground create a mechanical coupling and depending on the mode that can cause issues. If you use a speed controller the ESCs would start to work against each other, due to tolerances in the system. Basically one motor would try to speed another one up and that motor then tryies its best to work against that. Tiny differences then build up fast....
They are in speed control mode, and when testing, all 4 wheels have been running freely in the air.
Speed control will likeley cause issues with the wheels down. Did you detect each motor separately and did you use the latest BETA VESC-Tool?
https://vesc-project.com/node/2859
Dear all, have you found a solution on that issue? I've got the same problem with 3 VESC parallel with CAN-Bus. I am using latest firmware 6.2 and CAN-Cables with 120 Ohm at both ends.
I got four Flipsky 75/100s running over a breadboard CAN bus
about a month ago. So it's possible. Didn't do any real load testing but the motors didn't stutter. Currently switching to using an Arduino to control the VESCs using VESCUART. It also supports CAN control but the documentation is not great. Sometimes just re-running the motor wizard will fix your problems.
https://github.com/SolidGeek/VescUART
Edit: Note that the VESC devices have built in 220 ohm terminators, probably because they assumed you'd only have two devices on a bus so they'd be pre-terminated. The problem is that with four ESCs a VESC Express, you're looking at 5+ terminations on the CAN bus. Not sure if that's a problem or not but you may want to also try lowering the CAN rate.
I am having this issue with three or four flipsky 75100 and hoverboard motors in current mode wherls down, mostly at medium and up torque Low seems smoother. Do I need to remove some built in resistors? They do all share the same battery. Any other ideas?
ahanktcd