Little FOCer! 84V 5kW VESC-Based Controller

Hey @shaman. Great work and congrats on the accomplishment of the Little FOCer V3!

I’m looking to replace my OneWheel controller with a VESC and was wondering if you had considered adding light bar support to the Little FOCer. I talked to @surfdado about this on discord and he mentioned that currently the VESC open source spec/software doesn’t have support for lights, but if you added hardware support for it he would happily add firmware support for it.

But yeah, it would be nice to have GitHub - thankthemaker/rESCue: rESCue - add more safety and control to your VESC based vehicle built into the little FOCer so it would be truly plug and play replacement.

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So the Little FOCer’s onboard voltage supplies don’t quite have enough power for a light bar but the spare GPIO pins are there as a way to control external lights if wanted. So if the lights can be powered from a source other than the Little FOCer, then the Little FOCer can control the lights via the GPIO pins with special firmware.

Hmmm, something like this? https://www.amazon.com/Module-Supply-Converter-Non-Isolated-Stabilizer/dp/B09G56C9X5?th=1

Would I also need a mosfet to turn it off when the board is off?

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Have you looked into the rESCue?

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Finally got a new belt on:

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ooooo boyyyy these are the numbers i was looking for. got a full parts list for this? im looking to replicate this somehow

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This is awesome! Unlocking the full potential of 250A to the motor. Excellent thermal management!

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Well I hope to make a how to video of the water block on the focer but other than that I have a razor wiki where most of my parts and advice are at the moment:

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Thanks bud. I may tweak some values to try and get more performance out of it later but for now, it’s pretty fun. Thermals look good eh?

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What is the wheel sprocket fabrication?

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Oh, it’s a 3d printed rear and custom aluminum front. Hoping to have a kit available for others to use one day.

Brilliant work overall. Great to see 3D print holding up to the torque. What is the material?

Oh, thanks bud. It’s pla. I molded it around the old sprocket.



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Hi. I just wanted to place an order in the EU eShop and they are out of stock. Is restocking planned soon?

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The EU will be restocked as soon as possible. I got hit again by the chip shortage so I couldn’t restock the EU with v3.0 since it can’t be made again.

I’ve got v3.1 prototypes on hand right now being tested. That will go into production after I’m done evaluating it.

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So the v3.1 has different gate drivers, current sense amps, buck converter, IMU, and CAN transceiver. It also has more copper in the PCB for better thermals when pushing higher battery amps. So far everything checks out. Special thanks to @NuRxG for adapting the LSM6DS3 code to the slightly different LSM6DS3TR-C that I’m using now. A little more tuning to the gate driver stuff and it should be ready for high-current bench testing and then field testing.

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Keep up the good work! When you have an idea of how many battery amps it can do be sure to let me know :smiley:.

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Found a weird bug when being extra mean to the prototype. If I hammer it with sudden back and forth changes of motor direction on a unloaded motor (completely unrealistic scenario IMO) then it sometimes acts as if it losses calibration with one of the current sense inputs. Resetting the controller then fixes it. I stabilized the 15V rail with some extra capacitance and then wasn’t able to recreate the issue again. So the idea here is that if it can handle me brutalizing it on the bench, then chances are it does fine in the field if operated correctly.

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