File content as of revision 1:ec00f549a691:

#include "mbed.h"
#include "MPU6050.h"
#include "USBJoystick.h"

float sum = 0;
uint32_t sumCount = 0;

MPU6050 mpu6050;
Timer t;
Serial pc(USBTX, USBRX); 

PwmOut thruster1(D2);
PwmOut thruster2(D3);
PwmOut vibMotor(D4);
PwmOut onboardRed(LED_RED);
PwmOut onboardGreen(LED_GREEN);
PwmOut onboardBlue(LED_BLUE);
DigitalIn boost(D5);
DigitalIn drift(D6);

int boostCount = 0;

//commented out so that we can read from serial for now
USBJoystick joystick;

//input initializers for joystick
int16_t i = 0;
int16_t throttle = 0;
int16_t rudder = 0;    
float joyX = 0;
float joyY = 0;
int32_t radius = 120;
int32_t angle = 0;
int8_t button = 0;    
int8_t hat = 8;
float x, y;    

float maxRoll = 45;
float maxPitch = 135;
   
   
float mapRoll(float IMUpitch, float maxRoll) {
    
    if (IMUpitch < maxRoll && IMUpitch >= 0) {
        x = (IMUpitch*(127/maxRoll));
    } else if (IMUpitch > maxRoll) {
        x = 127;
    } else if (IMUpitch < -maxRoll) {
        x = -127;
    } else {
        x =  (IMUpitch*(127/maxRoll));
    }
    return x;
}

float mapPitch(float IMUroll, float maxPitch) {
    if (IMUroll > maxPitch && IMUroll <= 180) {
        y = ((180 - IMUroll) *(127/(180-maxPitch)));
    } else if (IMUroll < maxPitch && IMUroll >=0) {
        y = 127;
    } else if (IMUroll > -maxPitch && IMUroll < 0) {
        y = -127;
    } else {
        y =  (-(180 - abs(IMUroll)) *(127/(180-maxPitch)));
    }
    return y;
}
        
int main()
{
    onboardRed = 0.0f;
    onboardGreen = 1.0f;
    onboardBlue = 1.0f;
    //Set up I2C
    i2c.frequency(400000);  // use fast (400 kHz) I2C    
    t.start();
    boost.mode(PullUp);
    drift.mode(PullUp); 
    vibMotor = 1.0f;
           
    joystick.hat(hat);
    
    // Read the WHO_AM_I register, this is a good test of communication
    uint8_t whoami = mpu6050.readByte(MPU6050_ADDRESS, WHO_AM_I_MPU6050);  // Read WHO_AM_I register for MPU-6050
    pc.printf("I AM 0x%x\n\r", whoami); pc.printf("I SHOULD BE 0x68\n\r");
    
    if (whoami == 0x68) // WHO_AM_I should always be 0x68
    {  
        pc.printf("MPU6050 is online...");
        wait(1);
            
        mpu6050.MPU6050SelfTest(SelfTest); // Start by performing self test and reporting values
         
        pc.printf("x-axis self test: acceleration trim within : "); pc.printf("%f", SelfTest[0]); pc.printf("% of factory value \n\r");
        pc.printf("y-axis self test: acceleration trim within : "); pc.printf("%f", SelfTest[1]); pc.printf("% of factory value \n\r");
        pc.printf("z-axis self test: acceleration trim within : "); pc.printf("%f", SelfTest[2]); pc.printf("% of factory value \n\r");
        pc.printf("x-axis self test: gyration trim within : "); pc.printf("%f", SelfTest[3]); pc.printf("% of factory value \n\r");
        pc.printf("y-axis self test: gyration trim within : "); pc.printf("%f", SelfTest[4]); pc.printf("% of factory value \n\r");
        pc.printf("z-axis self test: gyration trim within : "); pc.printf("%f", SelfTest[5]); pc.printf("% of factory value \n\r");
        
        wait(2);

        if(SelfTest[0] < 1.0f && SelfTest[1] < 1.0f && SelfTest[2] < 1.0f && SelfTest[3] < 1.0f && SelfTest[4] < 1.0f && SelfTest[5] < 1.0f) 
        {
            mpu6050.resetMPU6050(); // Reset registers to default in preparation for device calibration
            mpu6050.calibrateMPU6050(gyroBias, accelBias); // Calibrate gyro and accelerometers, load biases in bias registers  
            mpu6050.initMPU6050(); pc.printf("MPU6050 initialized for active data mode....\n\r"); // Initialize device for active mode read of acclerometer, gyroscope, and temperature
        
            wait(2);
        } else {
                pc.printf("Device did not the pass self-test!\n\r");    
        } 
    } else {
        pc.printf("Could not connect to MPU6050: \n\r");
        pc.printf("%#x \n",  whoami);
        while(1) ; // Loop forever if communication doesn't happen
    }
    while(1) {
  
        // If data ready bit set, all data registers have new data
        if(mpu6050.readByte(MPU6050_ADDRESS, INT_STATUS) & 0x01) {  // check if data ready interrupt
            mpu6050.readAccelData(accelCount);  // Read the x/y/z adc values
            mpu6050.getAres();
        
            // Now we'll calculate the accleration value into actual g's
            ax = (float)accelCount[0]*aRes - accelBias[0];  // get actual g value, this depends on scale being set
            ay = (float)accelCount[1]*aRes - accelBias[1];   
            az = (float)accelCount[2]*aRes - accelBias[2];  
           
            mpu6050.readGyroData(gyroCount);  // Read the x/y/z adc values
            mpu6050.getGres();
         
            // Calculate the gyro value into actual degrees per second
            gx = (float)gyroCount[0]*gRes - gyroBias[0];  // get actual gyro value, this depends on scale being set
            gy = (float)gyroCount[1]*gRes - gyroBias[1];  
            gz = (float)gyroCount[2]*gRes - gyroBias[2];   
        
            tempCount = mpu6050.readTempData();  // Read the x/y/z adc values
            temperature = (tempCount) / 340. + 36.53; // Temperature in degrees Centigrade
        }  
   
        Now = t.read_us();
        deltat = (float)((Now - lastUpdate)/1000000.0f) ; // set integration time by time elapsed since last filter update
        lastUpdate = Now;
        
        sum += deltat;
        sumCount++;
        
        if(lastUpdate - firstUpdate > 10000000.0f) {
            beta = 0.04;  // decrease filter gain after stabilized
            zeta = 0.015; // increasey bias drift gain after stabilized
        }
        
        // Pass gyro rate as rad/s
        mpu6050.MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f);
    
        // Serial print and/or display at 0.5 s rate independent of data rates
        delt_t = t.read_ms() - count;
        if (delt_t > 500) { // update ////////////////////////lcd once per half-second independent of read rate

        /*
        pc.printf("ax = %f", 1000*ax); 
        pc.printf(" ay = %f", 1000*ay); 
        pc.printf(" az = %f  mg\n\r", 1000*az); 
    
        pc.printf("gx = %f", gx); 
        pc.printf(" gy = %f", gy); 
        pc.printf(" gz = %f  deg/s\n\r", gz); 
        
        pc.printf(" temperature = %f  C\n\r", temperature); 
        
        pc.printf("q0 = %f\n\r", q[0]);
        pc.printf("q1 = %f\n\r", q[1]);
        pc.printf("q2 = %f\n\r", q[2]);
        pc.printf("q3 = %f\n\r", q[3]);  */    
    
    
      // Define output variables from updated quaternion---these are Tait-Bryan angles, commonly used in aircraft orientation.
      // In this coordinate system, the positive z-axis is down toward Earth. 
      // Yaw is the angle between Sensor x-axis and Earth magnetic North (or true North if corrected for local declination, looking down on the sensor positive yaw is counterclockwise.
      // Pitch is angle between sensor x-axis and Earth ground plane, toward the Earth is positive, up toward the sky is negative.
      // Roll is angle between sensor y-axis and Earth ground plane, y-axis up is positive roll.
      // These arise from the definition of the homogeneous rotation matrix constructed from quaternions.
      // Tait-Bryan angles as well as Euler angles are non-commutative; that is, the get the correct orientation the rotations must be
      // applied in the correct order which for this configuration is yaw, pitch, and then roll.
      // For more see http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles which has additional links.
        yaw   = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]);   
        pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2]));
        roll  = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]);
        pitch *= 180.0f / PI;
        yaw   *= 180.0f / PI; 
        roll  *= 180.0f / PI;
    
        //pc.printf("Yaw, Pitch, Roll: \n\r");
        //pc.printf("Yaw: %f\n\r", yaw);
        //pc.printf(", ");
        //pc.printf("Pitch: %f\n\r", pitch);
        //pc.printf(", ");
        //pc.printf("%f\n\r", roll);
        //pc.printf("average rate = "); pc.printf("%f", (sumCount/sum)); pc.printf(" Hz\n\r");
    
        //pc.printf("Yaw, Pitch, Roll: %f %f %f\n\r", yaw, pitch, roll);
        //pc.printf("average rate = %f\n\r", (float) sumCount/sum);
  
    
        //Pitch: base = 0, right = +, left = -
        //Roll: base = +-180, forward = + count down, back = - count up
        
        joyX = mapRoll(pitch, maxRoll);
        joyY = mapPitch(roll, maxPitch);
        pc.printf("joyX: %i, joyY: %i\n\r", (int16_t) joyX, (int16_t) joyY);
        
        if (!boost && !drift) {
            button = 0x03;
            boostCount = 75;
        } else if (!boost && drift) {
            button = 0x01;
            boostCount = 75;
        } else if (boost && !drift) {
            button = 0x02;
        } else {
            button = 0x00;
        }            
        
        joystick.update(throttle, rudder, (int16_t)joyX, (int16_t)joyY, button, hat);
        if ((int16_t) joyY < 0) {
            onboardRed = 1.0f;
            onboardGreen = 1.0f;
            onboardBlue = 0.75f;
            thruster1 = 0.25f;
            thruster2 = 0.25f;
        } else if(lastUpdate - firstUpdate > 10000000.0f){
            onboardRed = 1.0f;
            onboardGreen = 0.0f;
            onboardBlue = 1.0f;
            thruster1 = 0;
            thruster2 = 0;
        }
        vibMotor = 0;
        if (boostCount != 0) {
            thruster1 = 1.0f;
            thruster2 = 1.0f;
            onboardRed = 1.0f;
            onboardGreen = 1.0f;
            onboardBlue = 0.0f;
            vibMotor = 1;
            boostCount--;
        }
        
        
        }
    }
 
}