void calibrate()
{
// at rest the accelerometer reports an acceleration straight upwards
// due to gravity. use this as our Z axis
Compass_ReadAccAvg(Zaxis, 500);
vecNorm(Zaxis);
// the magnetic strength is greatest towards magnetic north. use this as
// our X axis
Compass_ReadMagAvg(Xaxis, 10);
vecNorm(Xaxis);
// create a Y axis perpendicular to the X and Z axes
vecCross(Yaxis, Zaxis, Xaxis);
vecNorm(Yaxis);
// ensire that the X axis is actually perpendicular to the Y and Z axes
vecCross(Xaxis, Yaxis, Zaxis);
vecNorm(Xaxis);
// calibrate the zero error on the gyroscope
Gyro_ReadAngRateAvg(zeroAngRate, 100);
}
int main()
{
setvbuf(stdout, NULL, _IONBF, 0);
setvbuf(stderr, NULL, _IONBF, 0);
/*!< At this stage the microcontroller clock setting is already configured,
this is done through SystemInit() function which is called from startup
file (startup_stm32f30x.s) before to branch to application main.
To reconfigure the default setting of SystemInit() function, refer to
system_stm32f30x.c file
*/
/* SysTick end of count event each 10ms */
RCC_GetClocksFreq(&RCC_Clocks);
SysTick_Config(RCC_Clocks.HCLK_Frequency / 100);
/* initialise USART1 debug output (TX on pin PA9 and RX on pin PA10) */
USART1_Init();
//printf("Starting\n");
USART1_flush();
/*
printf("Initialising USB\n");
USBHID_Init();
printf("Initialising USB HID\n");
Joystick_init();
*/
/* Initialise LEDs */
//printf("Initialising LEDs\n");
int i;
for (i = 0; i < 8; ++i) {
STM_EVAL_LEDInit(leds[i]);
STM_EVAL_LEDOff(leds[i]);
}
/* Initialise gyro */
//printf("Initialising gyroscope\n");
Gyro_Init();
/* Initialise compass */
//printf("Initialising compass\n");
Compass_Init();
Delay(100);
calibrate();
int C = 0, noAccelCount = 0;
while (1) {
float *acc = accs[C&1],
*prevAcc = accs[(C&1)^1],
*vel = vels[C&1],
*prevVel = vels[(C&1)^1],
*pos = poss[C&1],
*prevPos = poss[(C&1)^1],
*angRate = angRates[C&1],
*prevAngRate = angRates[(C&1)^1],
*ang = angs[C&1],
*prevAng = angs[(C&1)^1],
*mag = mags[C&1],
*prevmag = mags[(C&1)^1];
/* Wait for data ready */
#if 0
Compass_ReadAccAvg(acc, 10);
vecMul(axes, acc);
//printf("X: %9.3f Y: %9.3f Z: %9.3f\n", acc[0], acc[1], acc[2]);
float grav = acc[2];
acc[2] = 0;
if (noAccelCount++ > 50) {
for (i = 0; i < 2; ++i) {
vel[i] = 0;
prevVel[i] = 0;
}
noAccelCount = 0;
}
if (vecLen(acc) > 50.f) {
for (i = 0; i < 2; ++i) {
vel[i] += prevAcc[i] + (acc[i]-prevAcc[i])/2.f;
pos[i] += prevVel[i] + (vel[i]-prevVel[i])/2.f;
}
noAccelCount = 0;
}
C += 1;
if (((C) & 0x7F) == 0) {
printf("%9.3f %9.3f %9.3f %9.3f %9.3f\n", vel[0], vel[1], pos[0], pos[1], grav);
//printf("%3.1f%% %d %5.1f %6.3f\n", (float) timeReadI2C*100.f / totalTime, C, (float) C*100.f / (totalTime), grav);
}
#endif
Compass_ReadMagAvg(mag, 2);
vecMul(axes, mag);
float compassAngle = atan2f(mag[1], mag[0]) * 180.f / PI;
if (compassAngle > 180.f) compassAngle -= 360.f;
//vecNorm(mag);
Gyro_ReadAngRateAvg(mag, 2);
printf("%6.3f:%6.3f,%6.3f,%6.3f\n", compassAngle, mag[0], mag[1], mag[2]);
#if 0
Gyro_ReadAngRateAvg(angRate, 2);
angRate[0] *= 180.f / PI;
angRate[1] *= 180.f / PI;
angRate[2] *= 180.f / PI;
float s[3] = {sin(angRate[0]), sin(angRate[1]), sin(angRate[2])};
float c[3] = {cos(angRate[0]), cos(angRate[1]), cos(angRate[2])};
float gyroMat[3][3] = {
{c[0]*c[1], c[0]*s[1], -s[1]},
{c[0]*s[1]*s[2]-s[0]*c[2], c[0]*c[2]+s[0]*s[1]*s[2], c[1]*s[2]},
{c[0]*s[1]*c[2]+s[0]*s[2], -c[0]*s[2]+s[0]*s[1]*c[2], c[1]*c[2]}};
/*
float gyroWorldMat[3][3];
vecMulMatTrans(gyroWorldMat, axes, gyroMat);
*ang = gyroWorldMat[2][0];
*ang += gyroWorldMat[2][1];
*ang += gyroWorldMat[2][2];
*ang /= 300.f;
static const float ANGALPHA = 0.0f;
*ang += ANGALPHA*(compassAngle - *ang);
*/
float rotObsVec[3];
memcpy(rotObsVec, axes[0], sizeof(rotObsVec));
vecMul(gyroMat, rotObsVec);
vecMul(axes, rotObsVec);
rotObsVec[2] = 0.f;
vecNorm(rotObsVec);
float angDelta = acos(rotObsVec[0]);
if (((++C) & 0x7) == 0) {
printf("%6.3f %6.3f %6.3f %6.3f\n", rotObsVec[0], rotObsVec[1], rotObsVec[2], angDelta);
}
#endif
#if 0
float angRate[3];
/* Read Gyro Angular data */
Gyro_ReadAngRate(angRate);
printf("X: %f Y: %f Z: %f\n", angRate[0], angRate[1], angRate[2]);
float MagBuffer[3] = {0.0f}, AccBuffer[3] = {0.0f};
float fNormAcc,fSinRoll,fCosRoll,fSinPitch,fCosPitch = 0.0f, RollAng = 0.0f, PitchAng = 0.0f;
float fTiltedX,fTiltedY = 0.0f;
Compass_ReadMag(MagBuffer);
Compass_ReadAcc(AccBuffer);
for(i=0;i<3;i++)
AccBuffer[i] /= 100.0f;
fNormAcc = sqrt((AccBuffer[0]*AccBuffer[0])+(AccBuffer[1]*AccBuffer[1])+(AccBuffer[2]*AccBuffer[2]));
fSinRoll = -AccBuffer[1]/fNormAcc;
fCosRoll = sqrt(1.0-(fSinRoll * fSinRoll));
fSinPitch = AccBuffer[0]/fNormAcc;
fCosPitch = sqrt(1.0-(fSinPitch * fSinPitch));
if ( fSinRoll >0)
{
if (fCosRoll>0)
{
RollAng = acos(fCosRoll)*180/PI;
}
else
{
RollAng = acos(fCosRoll)*180/PI + 180;
}
}
else
{
if (fCosRoll>0)
{
RollAng = acos(fCosRoll)*180/PI + 360;
}
else
{
RollAng = acos(fCosRoll)*180/PI + 180;
}
}
if ( fSinPitch >0)
{
if (fCosPitch>0)
{
PitchAng = acos(fCosPitch)*180/PI;
}
else
{
PitchAng = acos(fCosPitch)*180/PI + 180;
}
}
else
{
if (fCosPitch>0)
{
PitchAng = acos(fCosPitch)*180/PI + 360;
}
else
{
PitchAng = acos(fCosPitch)*180/PI + 180;
}
}
if (RollAng >=360)
{
RollAng = RollAng - 360;
}
if (PitchAng >=360)
{
PitchAng = PitchAng - 360;
}
fTiltedX = MagBuffer[0]*fCosPitch+MagBuffer[2]*fSinPitch;
fTiltedY = MagBuffer[0]*fSinRoll*fSinPitch+MagBuffer[1]*fCosRoll-MagBuffer[1]*fSinRoll*fCosPitch;
HeadingValue = (float) ((atan2f((float)fTiltedY,(float)fTiltedX))*180)/PI;
printf("Compass heading: %f\n", HeadingValue);
#endif
}
return 1;
}
int main()
{
setvbuf(stdout, NULL, _IONBF, 0);
setvbuf(stderr, NULL, _IONBF, 0);
/*!< At this stage the microcontroller clock setting is already configured,
this is done through SystemInit() function which is called from startup
file (startup_stm32f30x.s) before to branch to application main.
To reconfigure the default setting of SystemInit() function, refer to
system_stm32f30x.c file
*/
/* SysTick end of count event each 10ms */
RCC_GetClocksFreq(&RCC_Clocks);
SysTick_Config(RCC_Clocks.HCLK_Frequency / 100);
/* initialise USART1 debug output (TX on pin PA9 and RX on pin PA10) */
USART1_Init();
//printf("Starting\n");
USART1_flush();
/* Initialise LEDs */
//printf("Initialising LEDs\n");
int i;
for (i = 0; i < 8; ++i) {
STM_EVAL_LEDInit(leds[i]);
STM_EVAL_LEDOff(leds[i]);
}
/* Initialise gyro */
//printf("Initialising gyroscope\n");
Gyro_Init();
/* Initialise compass */
//printf("Initialising compass\n");
Compass_Init();
Delay(100);
// perform calibration
calibrate();
while (1) {
float angRate[3], mag[3];
// read average compass values
Compass_ReadMagAvg(mag, 2);
// rotate the compass values so that they are aligned with Earth
vecMul(axes, mag);
// calculate the heading through inverse tan of the Y/X magnetic strength
float compassAngle = atan2f(mag[1], mag[0]) * 180.f / PI;
// fix heading to be in range -180 to 180
if (compassAngle > 180.f) compassAngle -= 360.f;
// read average gyro values
Gyro_ReadAngRateAvg(angRate, 2);
// print out everything
printf("c%6.3f\ng%6.3f\n", compassAngle, angRate[2]-zeroAngRate[2]);
}
return 1;
}
