Stm32 custom encoder platformio

drajwer · December 5, 2023, 2:15am

Hi friends,

I’m about do integrate my custom encoder driven by SPI.

What are main changes in code I have to do while adding my specific encoder, apart from parametrizating a device? Have you encountered any difficulties??

VIPQualityPost · December 5, 2023, 3:25am

runger · December 6, 2023, 2:07pm

Hi @drajwer , welcome to SimpleFOC!

May I ask wich sensor it is you are integrating?

drajwer · December 9, 2023, 10:08pm

I’m using some magnetic sensor with more complex features.

drajwer · December 9, 2023, 10:14pm

Thanks, so I make all the necessary functions between my stm and sensor to communicate and read data constantly and then I just get data from those previous functions inside “readMySensorCallback”??

Or I rather should simply read specific variable through SPI inside the "readMySensorCallback?

float readMySensorCallback(){
 // read my sensor
 // return the angle value in radians in between 0 and 2PI
 return ...;
}

void initMySensorCallback(){
  // do the init
}

VIPQualityPost · December 9, 2023, 10:39pm

If it’s just using standard SPI, you can also use the generic MagneticSensorSPI class, I think.
If you need to implement a lot of special functions, then I would implement your SPI reads inside of readMySensorCallback

drajwer · December 11, 2023, 6:54pm

Hey runger, have you closed the loop with bldc?

If yes, did it go smooth in terms of implementation of algorithms or maybe you faced some issues?

Owen_Williams · December 11, 2023, 8:22pm

That is a bit vague. Can you link to a datasheet?

The genericSensor class is super easy to use. You have to implement an initSensor() and readSensor() method.

github.com

simplefoc/Arduino-FOC/blob/master/examples/utils/sensor_test/generic_sensor/generic_sensor.ino

/**
 *  Generic sensor example code 
 * 
 * This is a code intended to demonstrate how to implement the generic sensor class 
 * 
 */

#include <SimpleFOC.h>

// sensor reading function example
//  for the magnetic sensor with analog communication
// returning an angle in radians in between 0 and 2PI
float readSensor(){
  return analogRead(A0)*_2PI/1024.0;
}

// sensor intialising function
void initSensor(){
  pinMode(A0,INPUT);
}

This file has been truncated. show original

Then the GenericSensor can be linked to a the motor using same mechanism as other sensors types i.e. motor.linkSensor(&sensor):

github.com

simplefoc/Arduino-FOC/blob/6eed7b00c9bc1e9f7ea7984aa02a9f7ea98db19b/examples/motion_control/velocity_motion_control/magnetic_sensor/velocity_control/velocity_control.ino#L39


      
          float target_velocity = 0;
          // instantiate the commander
          Commander command = Commander(Serial);
          void doTarget(char* cmd) { command.scalar(&target_velocity, cmd); }
          
          void setup() {
          
            // initialise magnetic sensor hardware
            sensor.init();
            // link the motor to the sensor
            motor.linkSensor(&sensor);
          
            // driver config
            // power supply voltage [V]
            driver.voltage_power_supply = 12;
            driver.init();
            // link the motor and the driver
            motor.linkDriver(&driver);
          
            // set motion control loop to be used
            motor.controller = MotionControlType::velocity;

Once you’ve got GenericSensor working you could tidy things up and push the code into a dedicated class that extends the common Sensor class.

drajwer · December 11, 2023, 8:26pm

Thank you, appreciate your help

runger · December 12, 2023, 11:21am

Yes, absolutely, many times and with many different motors and sensors…

Sometimes it’s very easy, and not sensitive tot he parameters very much, and on other setups tuning can be very tricky.

It depends on many factors.