File content as of revision 21:302d9043cb4b:

#include "mbed.h"
#include "rtos.h"
//Photointerrupter input pins
#define I1pin D3
#define I2pin D6
#define I3pin D5

//Incremental encoder input pins
#define CHApin   D12
#define CHBpin   D11

//Motor Drive output pins   //Mask in output byte
#define L1Lpin D1           //0x01
#define L1Hpin A3           //0x02
#define L2Lpin D0           //0x04
#define L2Hpin A6          //0x08
#define L3Lpin D10           //0x10
#define L3Hpin D2          //0x20

#define PWMpin D9

//Motor current sense
#define MCSPpin   A1
#define MCSNpin   A0

//Test outputs
#define TP0pin D4
#define TP1pin D13
#define TP2pin A2

Serial pc(SERIAL_TX, SERIAL_RX);

float position_error = 0; 
float previous_position_error = 0 ;
float derivative_position = 0; 

// motor controller variables
float current_position = 0;
int previous_position = 0;
float velocity = 0;
Timer timer_velocity;
uint32_t last_time_MtrCtlr;
float pos_error_old;
int i = 0;

float integral=0;
float derivative=0;
float last_velocity_error = 0; 
//Mapping from sequential drive states to motor phase outputs
/*
State   L1  L2  L3
0       H   -   L
1       -   H   L
2       L   H   -
3       L   -   H
4       -   L   H
5       H   L   -
6       -   -   -
7       -   -   -
*/
//Drive state to output table
const int8_t driveTable[] = {0x12,0x18,0x09,0x21,0x24,0x06,0x00,0x00};

//Mapping from interrupter inputs to sequential rotor states. 0x00 and 0x07 are not valid
const int8_t stateMap[] = {0x07,0x05,0x03,0x04,0x01,0x00,0x02,0x07};
//const int8_t stateMap[] = {0x07,0x01,0x03,0x02,0x05,0x00,0x04,0x07}; //Alternative if phase order of input or drive is reversed

// PARAMETERS //
const float kp_vel = 20;
const float ki_vel = 0.00; 
const float kd_vel = 0.00; 

const float kp_pos = 0.05;
const float kd_pos = 0;
const float pwm_period  =0.25f;

int target_velocity = 30;
float target_position = 500;

// SHARED GLOBAL VARIABLES //
Semaphore pos_semaphore(0);
int position = 0;
bool direction = 1;

int lead = 2;

// NON-SHARED GLOBAL VARIABLES //
int lead_old;

//Status LED
DigitalOut led1(LED1);

//Photointerrupter inputs
InterruptIn I1(I1pin);
InterruptIn I2(I2pin);
InterruptIn I3(I3pin);

//Motor Drive outputs
DigitalOut L1L(L1Lpin);
DigitalOut L1H(L1Hpin);
DigitalOut L2L(L2Lpin);
DigitalOut L2H(L2Hpin);
DigitalOut L3L(L3Lpin);
DigitalOut L3H(L3Hpin);

DigitalOut TP1(TP1pin);
PwmOut MotorPWM(PWMpin);

Ticker motorCtrlTicker;
Thread thread_motorCtrl (osPriorityNormal,1024);

volatile int8_t orState = 0;    //Rotot offset at motor state 0
volatile int8_t intState = 0;
volatile int8_t intStateOld = 0;


//Set a given drive state
void motorOut(int8_t driveState)
{

    //Lookup the output byte from the drive state.
    int8_t driveOut = driveTable[driveState & 0x07];

    //Turn off first
    if (~driveOut & 0x01) L1L = 0;
    if (~driveOut & 0x02) L1H = 1;
    if (~driveOut & 0x04) L2L = 0;
    if (~driveOut & 0x08) L2H = 1;
    if (~driveOut & 0x10) L3L = 0;
    if (~driveOut & 0x20) L3H = 1;

    //Then turn on
    if (driveOut & 0x01) L1L = 1;
    if (driveOut & 0x02) L1H = 0;
    if (driveOut & 0x04) L2L = 1;
    if (driveOut & 0x08) L2H = 0;
    if (driveOut & 0x10) L3L = 1;
    if (driveOut & 0x20) L3H = 0;
}

//Convert photointerrupter inputs to a rotor state
inline int8_t readRotorState()
{
    return stateMap[I1 + 2*I2 + 4*I3];
}


void move()
{
    intState = readRotorState();

    // Updates direction only if statechanges by 1
    // If state chance is missed then interrupt is unchanged
    if( intState == 0 && intStateOld == 5) {
        direction = 1;
        position++;
    } else if( intState == 5 && intStateOld == 0) {
        direction = 0;
        position--;
    } else if ( intState == intStateOld + 1 ) {
        direction = 1;
        position++;
    } else if (intState == intStateOld - 1) {
        direction = 0;
        position--;
    }

    pos_semaphore.release();

    intStateOld = intState;

    motorOut((intState-orState+lead+6)%6); //+6 to make sure the remainder is positive
    }


void motorCtrlTick()
{
    thread_motorCtrl.signal_set(0x1);
    //osSignalSet(thread_motorCtrl, 0x1);
}

float get_velocity_out(float velocity_error)
{   
    integral += velocity_error; 
    derivative = velocity_error - velocity_error; 
    float velocity_out = (kp_vel*velocity_error) + (ki_vel*integral) + (kd_vel*derivative); 
    last_velocity_error = velocity_error; 
    return velocity_out;
}

float get_y_pos(float e, float change_e)
{
    return kp_pos*e + kd_pos*change_e;
}

float get_motor_out(float velocity_out)
{
    float motor_out;
    if( velocity_out < 0) {
        motor_out = velocity_out*-1;
    } else {
        motor_out = velocity_out;
    }
    if (velocity_out > 1 || velocity_out < -1) {
        motor_out = 1;
    }
    return motor_out;
}

int get_current_position(){
    pos_semaphore.wait();
    return position;
}

void attach_ISR(){
    I1.rise(&move);
    I1.fall(&move);
    I2.rise(&move);
    I2.fall(&move);
    I3.rise(&move);
    I3.fall(&move);
}


float combine_speed(float y_pos, float velocity_out, float velocity_error)
{
    if(velocity_error >= 0) {
        if(y_pos < velocity_out) {
            return y_pos;
        } else {
            return velocity_out;
        }
    } 
    else {
        if(y_pos > velocity_out){
            return y_pos;
        }
        else{
            return velocity_out;   
        }
    }
    return y_pos;
}


void update_lead(float velocity_out){    
    // No functionality for breaking
    if(velocity_out >= 0){
        lead = 2;
    }
    else {
        lead = -2;
    }

}
void motorInitSequence()
{
    motorCtrlTicker.attach_us(&motorCtrlTick,100000);
    pos_error_old = target_position;
    last_time_MtrCtlr = 0;
    
    MotorPWM.write(1);
    MotorPWM.period(pwm_period);

    motorOut(0);
    wait(3.0);
    orState = readRotorState();
    attach_ISR();

    if(target_velocity > 0){
        lead = 2;
        motorOut(1);
        wait(0.1); 
        motorOut(2); 
        wait(0.1); 
        motorOut(3); 
    }
    else{
        lead = -2;
        motorOut(5); 
        wait(0.3); 
        motorOut(4);
        wait(0.3); 
        motorOut(3); 
        wait(0.3); 
        motorOut(4); 

    }
    current_position = get_current_position();
    previous_position = current_position;
    timer_velocity.start();
}

void motorCtrlFn()
{    
    while(1) {
        thread_motorCtrl.signal_wait(0x1);
        current_position = get_current_position();
        float velocity_factor = (1000/(timer_velocity.read_ms()-last_time_MtrCtlr));
        velocity = ((current_position - previous_position)/6)*velocity_factor;
        last_time_MtrCtlr = timer_velocity.read_ms();
        previous_position = current_position;
        float velocity_error = target_velocity - velocity;

        
        
        position_error = target_position - (current_position/6); 
    
        float velocity_out = get_velocity_out(position_error);
        float position_out = (6*position_error) +  (40*derivative_position); 
        derivative_position = position_error - previous_position_error; 
        previous_position_error = position_error; 

        float motor_out = get_motor_out(velocity_out);      




        update_lead(position_out);
                        
        MotorPWM.period(pwm_period);
        MotorPWM.write(motor_out);

            if(i > 10) {
                pc.printf("Velocity = %f, Position = %f, MotorOut = %f, y = %f, lead = %d\r\n", velocity, (current_position/6), motor_out, derivative_position, lead);
                i = 0;
            }
        i++;
        }   
    }


//Main
int main()
{
    motorInitSequence();
    thread_motorCtrl.start(motorCtrlFn);

}