How to tune Advanced Sensorless Startup?

The question was

So how can one check if their hardware supports ass or not?

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AFAIK, ass works on all VESC based hardware running the latest builds. That said, it runs much better on designs which feature switchable phase filters.

For now it looks like that is the VESC6 MKV, VESC HD and STORMCORE 60D+

To the best of me knowledge it should run on other hardware but how well is anyone’s guess?

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I have this, so it should work. Awesome.

Nope, A.S.S requires special filtering. If the HW doesn’t support it, it will not work.

So then the question is more important than ever.

@Trampa Are you suggesting the only way to know is to cross-reference a list?

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is this what you mean?

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If the hardware “doesn’t support it”, you can easily (or not so easily) add the necessary capacitors yourself, depending on your soldering ability.

I reccomend a value of 15nF.
The capacitor goes in parallel with the bottom side resistor on the phase voltage divider.

It should not have adverse affects outside of ASS if everything else is working properly in firmware.
Though now that I think about, it may cause a kick leaving high speed coast if firmware doesn’t compensate for it, so please do a lot of testing if you decide to attempt this.

Nevermind, it would be best to simply leave the hardware alone as the firmware is sensitive to minor changes in hardware.

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The question-dodging is crazy around these parts

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Nope, you need to be able to adjust the filtering wile you start up the motor.

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Which entails adding an additional capacitor so that the cutoff frequency of the filter rejects PWM.

In fact having a capacitor soldered directly would work better since you dont have the very high on resistance of the analog switch in the way.

Basically all ASS is doing is lowering the minumum speed for BEMF to work by trying to eliminate inverter nonlinearities from the voltage terms. Hence why Vedder himself said it works best on a motor that is already spinning.

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If the HW isn’t specified to support this new method, I would assume it is not prepared HW wise.

So the intention is the only thing that makes you hesitate to say its compatible? If a new ESC running VESC6 firmware was designed from the ground up to run A.S.S would you acknowledge it?

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They need to test it out and see if it works. I can only speak for our HW.

I see

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I can’t find A.S.S support in their description. I assume they would advertise it if it would support it.

also this

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Can A.S.S fuck you up like field weakening can? Is it risky to test?

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No, there is a much lower risk.

Just dont test it at an intersection.

The HFI blip might launch you backwards.

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Soooo?

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