Steer by wire concept with brushless motors/servos FOC, help with PWM noise

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Hey guys, I am trying to learn more about how modern car steering systems work (steer by wire).

So I built this prototype.

Im using two brushless motors of different sizes, each equipped with an AS5048 absolute encoder for position feedback.

I can vary the ratio between motors, so 1 turn on one equals 3 turns on the second one, and when I move one motor, the other motor moves too, yet if I block the second motor, then the first motor shows more torque to be turned... giving feedback on what is happening on the other side.

I believe this could be of work for example on a remote control car, where the steering input could give some feedback on whats going on at the wheels of the car, just like real steering systems provide feedback to the drivers.

Video is here:Arduino Steer by wire attempt using brushless gimball motors and AS5048 Arduino Mega - YouTube

Can someone help me to eliminate the PWM noise? its currently around 1.6kHz, and really annoying, is there a way of doing this at 20kHz or more so I cant listen to it?

thanks!

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Juanpablocanguro:
Can someone help me to eliminate the PWM noise? its currently around 1.6kHz, and really annoying, is there a way of doing this at 20kHz or more so I cant listen to it?

You have not provided any information that we could use to help you.

Presumably you have some BLDC controllers between your Arduino and the motor. Post a link to the datasheet for the controllers and post your Arduino program.

There is probably a lot more that you know and we don't so please don't be shy about giving us info.

...R

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The BLDC controller I used for this example is the L6234, yet I dont think it is that relevant as analogWrite uses its standard frequency, no matter what power stage you use, but if what you want is more info on how to drive a BLDC using FOC, I have a thread in Motor Control Group.

Anyways, I was able to completely eliminate the noise on a similar setup but with an Arduino UNO using the following commands:

TCCR0B = TCCR0B & B11111000 | B00000010;
TCCR1B = TCCR1B & 0b11111000 | 0x01; 
TCCR2B = TCCR2B & 0b11111000 | 0x01; 
ICR1 = 255

It works like a charm... I can make the motor behave as a position servo, as a haptic device providing feedback, control the torque and generate different "clack" positions at will, mmmh, hard to explain, I will make a video soon.