Tests Yaw angle
Dependencies: MPU6050IMU mbed
Diff: main.cpp
- Revision:
- 0:98f7c7d55051
- Child:
- 2:8b8ea2b74666
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/main.cpp Sun Feb 15 17:40:56 2015 +0000 @@ -0,0 +1,125 @@ +// SDA --- A4 +// SCL --- A5 + +#include "mbed.h" +#include "MPU6050.h" + +float sum = 0; +uint32_t sumCount = 0; + +MPU6050 mpu6050; +Timer t; +Serial pc(USBTX, USBRX); // tx, rx + +int main(){ + pc.baud(9600); + + //Set up I2C + i2c.frequency(400000); // use fast (400 kHz) I2C + t.start(); + + // 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){ + 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(1); + + 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 + + pc.printf("\nMPU6050 passed self test... Initializing"); + wait(2); + } else pc.printf("\nDevice 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 + + 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: %f %f %f\n\r", yaw, pitch, roll); + pc.printf("average rate = %f\n\r", (float) sumCount/sum); + + count = t.read_ms(); + sum = 0; + sumCount = 0; + } + } + +} \ No newline at end of file