File content as of revision 23:e5a2e8cef243:

#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);



// Controller variables
Timer timer_velocity;
uint32_t last_time_MtrCtlr;
int i = 0;

// Velocity Controller Variables
float target_velocity = 30;
float integral_vel = 0; 
float derivative_vel = 0; 
float last_vel_error = 0; 

int previous_position = 0;
int current_position = 0; 

float kp_vel = 20;
float ki_vel = 0; 
float kd_vel = 0; 

// Position Controller Variables
float target_position = 500;
float integral_pos = 0; 
float derivative_pos = 0; 
float last_pos_error = 0; 

float kp_pos = 20;
float ki_pos = 0; 
float kd_pos = 10; 


//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

const float pwm_period  =0.25f;



// SHARED GLOBAL VARIABLES //
Semaphore pos_semaphore(0);
float 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_vel_control_out(float velocity_error)
{   
    integral_vel += velocity_error; 
    derivative_vel = velocity_error - last_vel_error; 
    float velocity_out = (kp_vel*velocity_error) + (ki_vel*integral_vel) + (kd_vel*derivative_vel); 
    last_vel_error = velocity_error; 
    return velocity_out;
}

float get_pos_control_out(float position_error){
    integral_pos += position_error; 
    derivative_pos = position_error - last_pos_error; 
    float velocity_out = (kp_pos*position_error) + (ki_pos*integral_pos) + (kd_pos*derivative_pos); 
    last_pos_error = position_error; 
    return velocity_out;  
}

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_control_out(float position_control_out, float velocity_control_out, float current_velocity)
{
    float velocity_out = 0; 
    if(current_velocity <= 0) {
        velocity_out = std::max(position_control_out, velocity_control_out);    } 
    else {
        velocity_out = std::min(position_control_out, velocity_control_out); 
    }
    return velocity_out;
}

float get_current_velocity(float current_position) {
        float velocity_factor = (1000/(timer_velocity.read_ms()-last_time_MtrCtlr));
        float velocity = ((current_position - previous_position)/6)*velocity_factor;
        last_time_MtrCtlr = timer_velocity.read_ms();
        previous_position = current_position; 
        return velocity; 
}

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);
    last_pos_error = 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;
        for (int i = 1; i<4; i++){
            motorOut(i);
            wait(0.2); 
        }
    }
    else{
        lead = -2;
        for (int i = 5; i > 2 ; i --){
            motorOut(i);
            wait(0.2); 
        }
    }
    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 current_velocity = get_current_velocity(current_position); 

        float velocity_error = target_velocity - current_velocity;       
        float velocity_control_out = get_vel_control_out(velocity_error); 
        
        float position_error = target_position - (current_position/6); 
        float position_control_out = get_pos_control_out(position_error);

        float velocity_out = combine_control_out(position_control_out, velocity_control_out, current_velocity); 
        float motor_out = get_motor_out(position_control_out);      

        update_lead(velocity_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", current_velocity, (position/6), motor_out, velocity_out, lead);
            i = 0;
        }
        i++;
        }   
    }


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

}