with the unity under active development, i thought we could persuade @Deodand to finally address the locking brakes issue for larger diameter wheels in FOC.
@thisguyhere, you ordered a unity, and have a board that exhibits this behavior? When you have your unit in hand mind spending a couple hours with me debugging/solving the issue? Basically get the board setup with the issue active, we will test a few config settings, if that doesn’t work then I’ll send you some modified FW to test with different fixes. Once I find a fix I’ll open an issue on Vedder’s git so it gets fixed there as well.
If anyone with a beta unit has the issue I could start testing sooner.
Detailed descriptions of the problem, and also if it occurs in FOC/BLDC, Sensored/unsensored, and what is wheel diameter motor kv and gearing would be helpful.
Yup, all my builds have this and I have learned to live with it. I just don’t understand how it is like this going forward but “slowing down” and stopping while in reverse doesn’t produce it. If that makes sense.
One thing that I’ll be implementing is scaling the plethora of erpm based settings based on motor flux-linkage during config. Essentially the flux linkage determines the amount of volts for a given ERPM, the amount of volts determines the signal quality that the unity has, and so for instance when to switch over from hall sensors to sensorless should just scale with the motor flux linkage and not require an additional config setting to work properly.
I’ve always had this issue to some degree regardless of gearing/wheel size on my FOC sensored 10S setup. I’ve learned to live with it, but it would be great to not have to deal with it.
I’m not hip to how this stuff works, but talk of scaling something based on the back emf/erpm or whatever sounds sexy… This issue is one of those SUDDEN type things, and if it were even to just ramp slowly into the locking brakes that would be so much nicer.
Are you talking about the full short braking when you reach a certain eRPM threshold? I thought there was a setting for this in 2.xx firmware which seems to be missing in 3.xx; or at least i can’t find it.
I got used to the locking brakes but would love to get rid of it. My bigger problem is when riding really steep downhill with my MTB with full braking, often the wheels block 100% and I start slipping or fall. This is really annoying. I have Vesc6 FW 3.38 with 149kv 6374’s running in FOC (12s) with 1:5 gearing on 8" wheels.