20bit incremental encoder supported?

I’m this close :pinching_hand: to buying 3 nos ac servo motors for cheap (for my driver I’m developing), they have 20 bit incremental encoders, and I’m wondering if simplefoc support’s 20bit encoders.

Hey @Franz_Schmidt

That is an interesting question :smiley:
The biggest PPR I’ve worked with so far is 8192, being quadrupled to 32000 impulses(CPR) per revolution. With this CPR you can get your motor to spin smoothly under 0.1 per second :smiley:

But this kinds of encoders rule out Arduinos and similar MCUs. In my experience even with the stm mcus, with 32000 cpr I was not able to reach the full motor speed.
The issue is the interrupt based encoder implementation, to use the full potential of the 20bit encoder we’d need to implement the hardware counter based encoder implementation.

It is not too difficult to do, but it would not scale well to different architectures unfortunately, so so fat we have not opted to go in this direction. But I would be interested to support and help any development and anyone who would be interested to contribute to this. :smiley:

I’m using a esp32, if i end up buying them i always could change out the encoder for a as5047 or something.

So i just bought all 3 for 200€ 2.3nm at 3000rpm 230v ac,

I’m really curious if the encoder will work.:crossed_fingers:

:clap: :clap: :clap:

Damn… :bowing_man:

Seams like the people on ebay only want the fanuc servos, they are going for 300€ a piece for roughly the same spec, the ones I bought are Schneider electric.🤷😂

There are also some more obscure German ones that probably go tomorrow for the starting bid at around 30€ maybe I will get some too.

Most stm32s have some form of hardware quadrature counter. Teensy also has 3.

You’ll also likely need to use a 64bit integer to store the count so you don’t get rollover.

I’m going to make my board modular so i don’t have to redo the whole thing when I want to try a new mcu