Hello,
there are tons of implementations of stewart platforms using servo motors as actuators. They all have one problem: they are very noisy on operation. For my usecase, I need the system to act as quietly as possible. Fast reaction and durability are also desired.
The System should be able to record an episode of movement to e.g. a sd-card and reproduce it later.
So seeing, what can be done with simplefoc and stepper motors, I came up with the idea to use a typical servo motor design but replace the six servo motors with nema 17 steppers equipped with magnetic encoders.
For the proof of concept, I chose a low cost setup with AS5600 and a I2C multiplexer from Adafruit (reason: all AS5600 have the same I2C address). For computation I took a Nucleo 64 / F401RE and the raw readings from all encoders seem to work fine.
The next problem is motor contol: For 6 nema 17 steppers, I need 6 x 4 = 24 pwm-outputs. So again some kind of multiplexing ist necessary. I found a 24ch pwm multiplexer on aliexpress, normaly used for LEDs and ordered it.
The longer I think of it, the more I get concerned about the needed computing power. So I need some imput from the community: Am I going in the right direction? Or should I try a completely other road by e.g. getting some cnc- or 3d-printer-boards that can handle up to 8 steppers?
Your thoughts are very welcome …
Martin