VESC current control problem

ESK8 Electronics
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1

Hi folks! I try to control my VESC 6 using an arduino nano.

I use FOC with “Current” setting and the latest firmware. The motor direction test spins the motor very nice and smoothly. The RT app display in vesc tool shows the correct input values and the motor spins up once.

However the motor does not spin up again after ppm is set to neutral (1500). I have to reverse it (1400) or turn it in the opposite direction manually.

Could you please confirm that VESC 6 does work using the servo library and maybe provide some debug tips? Thank you very much!

#include <Servo.h>
Servo servo;
int ppmOut = 11;
int ppmTestValue = 1500;

void setup() {
  Serial.begin(9600);
  servo.attach(ppmOut);
}

void loop() {
  if (Serial.available() > 0) {
    int ppmTestValue = Serial.parseInt();  
    if(ppmTestValue > 0){
      Serial.print("I received: ");
      Serial.println(ppmTestValue, DEC);
      servo.writeMicroseconds(ppmTestValue);
    }
  }
}
2

Doesn’t matter what VESC u use.

Check the open source remotes for reference. FeatherRemote, firefly remote… all work with ppm and VESC 6

3

I see, so the servo library should work. I reuploaded the firmware to clear the settings and reconfigured everything but the problem remains.

Do you think the arduino setup is fine if the vesc tool shows the correct ppm values?

4

Share your code… it should work normally.

5

See my first post for the code.

I chose “Current” mode and send 1600 which worked!

I discovered when I send 1500 which is neutral I am not able to drive the motor anymore afterwards except I send 1440 or less. Please note that i set safe start to false.

This basically means that i have to reverse the direction (brake) or turn the motor backward manually to spin the motor up a second time.

6

Sounds like you’ve set your ppm endpoints wrong in vesc tool.

7

Do you mean “Pulselength Start, End and Center” ? I went with the default settings. Vesc tool always shows the correct values but the motor doesn’t spin up again as described above.

8

Post a screenshot please.

10

Try turning on the pulselength mapping option at the bottom, then using the arduino to send both maximum and minimum commands.

11

test It’s so strange. Could it be a hall sensor problem? I think I got the mapping correct.

12

Did you apply the new pulselength settings?

13

yes i did.

1500, 1600, 1700 works like it should

1500, 1600, 1400, 1600 spins up twice as it’s supposed to

1500, 1600, 1500, 1600 does spin up only once, second 1600 gets ignored

1500, 1600, 1500, manually turn the motor in the opposite direction, then 1600 works

14

Hmm, weird. I’ll mull it over some more, but I gotta hit the hay for tonight.

15

thank you for trying to help :slight_smile:

18

I noticed the arrow key motor control also works in PPM mode if the arduino isn’t connected or if it does not run “servo.attach(ppmOut)” at all.

With the arduino connected arrow key control in vesc tool doesn’t work, no matter what output pin i choose. Can anyone confirm this behaviour?

19

You don’t need to ground any ADC. How do you connect the Arduino to the VESC? Isn’t the problem that you connect the servo signal to the ADC pin on the COMM port rather than to the servo port?

20

No i checked the connections. After trying ADC (and the comm port) i switched back to PPM (with the servo pin). I don’t know why i have to turn the motor backwards before it spins up again.

21

This is related to current control types. In duty cyles control types i don’t experience the problem.

22

Solved it by using “Current No Reverse With Brake”