├── README.md
└── i2c_motor_control_test.ino


/README.md:
--------------------------------------------------------------------------------
 1 | # BLDC-Motorcontroller
 2 | This is a very simple sketch to control two BLDC motors using the STEVAL-GMBL02V1, SimpleFOC library and Arduino IDE.   
 3 | Motors are iPower GM3506 with internal AS5048A encoders.   
 4 | 
 5 | I'm using Tourqe as MotionControlType and Voltage as TourqeControlType. This is because the STEVAL-GMBL02V1 sadly only offers a single shunt per motor connection, making Current control impossible (using SimpleFOC v2.2.2 at least).    
 6 | 
 7 | The controller is managed via I2C connection to a Raspberry Pi and receives relevant speed and steering data.
 8 | 
 9 | # Findings regarding the STEVAL-GMBL02V1   
10 | I didn't find much information about the STEVAL-GMBL02V1 online, so i collected everything here in case anyone else might be interested in it.   
11 | - The documentation notes "6V to 8.4VDC bus voltage range, which you can increase to 11V". It isn't mentioned again, and should be taken with a grain of salt, as the STSPIN233 driver has an operating voltage between 1.8 and 10V, with 11V being the absolute maximum rating for it.
12 | - I2C can be wired via PB9/SDA and PB8/SCL, or if absolutely neccessary there is another I2C pin in the 10 pin header for the STLink connection. You will need to overwrite the SWD pins for this, so take care.
13 | - BOOT0 is hardwired to GND, so you'll need a small probe to pull it high.
14 | 


--------------------------------------------------------------------------------
/i2c_motor_control_test.ino:
--------------------------------------------------------------------------------
  1 | #include <Wire.h>
  2 | #include <SimpleFOC.h>
  3 | 
  4 | /*
  5 |    Rotary Encoder Wires:
  6 |    Purple - PWM -  Gray
  7 |    Green  - GND -  Black
  8 |    Blue   - 5V  -  White
  9 | */
 10 | 
 11 | #define SENSORPWM1 PB6
 12 | #define SENSORPWM2 PB7
 13 | 
 14 | #define LEDPIN PA7
 15 | #define SLAVEADDRESS 0x8
 16 | #define SDAPIN PB9
 17 | #define SCLPIN PB8
 18 | 
 19 | #define SUPPLYVOLTAGE 8.4
 20 | #define VOLTAGELIMITDRIVER 6
 21 | #define VOLTAGELIMITMOTOR 3
 22 | #define MOTORRESISTANCE 5.57
 23 | 
 24 | #define SENSORMINPULSE 7
 25 | #define SENSORMAXPULSE 935
 26 | 
 27 | #define POLEPAIRS 11
 28 | #define CLOSEDLOOP true
 29 | 
 30 | #define MESSAGESIZE 8
 31 | #define MAXTARGETVELOCITY 50
 32 | #define MAXTARGETCURRENT 10
 33 | #define MAXTARGETVOLTAGE 6
 34 | 
 35 | BLDCMotor motor1 = BLDCMotor(POLEPAIRS, MOTORRESISTANCE);
 36 | BLDCDriver3PWM driver1 = BLDCDriver3PWM(PC0, PC1, PC2, PC13);
 37 | MagneticSensorPWM sensor1 = MagneticSensorPWM(SENSORPWM1, SENSORMINPULSE, SENSORMAXPULSE);
 38 | 
 39 | BLDCMotor motor2 = BLDCMotor(POLEPAIRS, MOTORRESISTANCE);
 40 | BLDCDriver3PWM driver2 = BLDCDriver3PWM(PA0, PA1, PA2, PC14);
 41 | MagneticSensorPWM sensor2 = MagneticSensorPWM(SENSORPWM2, SENSORMINPULSE, SENSORMAXPULSE);
 42 | 
 43 | char message[MESSAGESIZE];
 44 | float motorTargetCurrent = 0;
 45 | float motorTargetVelocity = 0;
 46 | float motorTargetVoltage = 0;
 47 | 
 48 | void setup()
 49 | {
 50 |   blink(2, 100);
 51 | 
 52 |   initI2C();
 53 |   initMotors();
 54 | 
 55 |   blink(3, 200);
 56 | }
 57 | 
 58 | void loop()
 59 | {
 60 |   // main FOC algorithm function
 61 |   motor1.loopFOC();
 62 |   motor2.loopFOC();
 63 | 
 64 |   // Motion control function
 65 |   motor1.move(motorTargetVoltage);
 66 |   motor2.move(motorTargetVoltage);
 67 | }
 68 | 
 69 | void blink(int amount, int del) {
 70 |   pinMode(LEDPIN, OUTPUT);
 71 | 
 72 |   for (int i = 0; i < amount; i++) {
 73 |     digitalWrite(LEDPIN, HIGH);
 74 |     delay(del);
 75 |     digitalWrite(LEDPIN, LOW);
 76 |     delay(del);
 77 |   }
 78 | }
 79 | 
 80 | void initI2C() {
 81 |   Wire.setSDA(SDAPIN);
 82 |   Wire.setSCL(SCLPIN);
 83 |   Wire.begin(SLAVEADDRESS);
 84 |   Wire.onReceive(receiveFun);
 85 |   Wire.onRequest(requestFun);
 86 | }
 87 | 
 88 | void initMotors() {
 89 |   pinMode(SENSORPWM1, INPUT);
 90 |   pinMode(SENSORPWM2, INPUT);
 91 | 
 92 |   sensor1.init();
 93 |   motor1.linkSensor(&sensor1);
 94 |   driver1.voltage_power_supply = SUPPLYVOLTAGE;
 95 |   driver1.voltage_limit = VOLTAGELIMITDRIVER;
 96 |   driver1.init();
 97 |   motor1.linkDriver(&driver1);
 98 |   motor1.voltage_limit = VOLTAGELIMITMOTOR;
 99 |   motor1.voltage_sensor_align = VOLTAGELIMITMOTOR;
100 |   motor1.torque_controller = TorqueControlType::voltage;
101 |   motor1.controller = MotionControlType::torque;
102 |   motor1.init();
103 |   motor1.initFOC();
104 | 
105 |   sensor2.init();
106 |   motor2.linkSensor(&sensor2);
107 |   driver2.voltage_power_supply = SUPPLYVOLTAGE;
108 |   driver2.voltage_limit = VOLTAGELIMITDRIVER;
109 |   driver2.init();
110 |   motor2.linkDriver(&driver2);
111 |   motor2.voltage_limit = VOLTAGELIMITMOTOR;
112 |   motor2.voltage_sensor_align = VOLTAGELIMITMOTOR;
113 |   motor2.torque_controller = TorqueControlType::voltage;
114 |   motor2.controller = MotionControlType::torque;
115 |   motor2.init();
116 |   motor2.initFOC();
117 | }
118 | 
119 | void receiveFun (int bytes)
120 | {
121 |   int i = 0;
122 |   while (Wire.available() && i < MESSAGESIZE)
123 |   {
124 |     message[i] = Wire.read();
125 |     i++;
126 |   }
127 | 
128 |   float spd = message[1];
129 |   float str = message[2];
130 | 
131 |   //de-normalize values
132 |   spd = spd - 128;
133 |   spd = spd / 128 * MAXTARGETVOLTAGE;
134 |   motorTargetVoltage = spd;
135 | }
136 | 
137 | void requestFun()
138 | {
139 |   // Convert from angular rad/s to linear velocity m/s
140 |   // TODO calculate correct conversion factor
141 |   float vel = sensor1.getVelocity() + sensor2.getVelocity() / 2 * WHEELRADIUS;
142 |   // TODO check I2C float specs, convert if neccessary
143 |   Wire.write(vel);
144 | }
145 | 


--------------------------------------------------------------------------------