Mbed electronic "bubble level." Uses LSB9DS1 9-degrees-of-freedom IMU to determine orientation and prints bubble display to LCD screen.
Dependencies: 4DGL-uLCD-SE LSM9DS1_Library_cal mbed
main.cpp
- Committer:
- wschon
- Date:
- 2016-02-13
- Revision:
- 0:8079f51a9835
File content as of revision 0:8079f51a9835:
#include "mbed.h" #include "LSM9DS1.h" #include "uLCD_4DGL.h" #define PI 3.14159 // Earth's magnetic field varies by location. Add or subtract // a declination to get a more accurate heading. Calculate // your's here: // http://www.ngdc.noaa.gov/geomag-web/#declination #define DECLINATION -4.94 // Declination (degrees) in Atlanta,GA. DigitalOut myled(LED1); Serial pc(USBTX, USBRX); float accel_x, accel_y, accel_z; int outer_radius = 9; int radius = 3; uLCD_4DGL uLCD(p9,p10,p11); // serial tx, serial rx, reset pin; int x,y; // Calculate pitch, roll, and heading. // Pitch/roll calculations taken from this app note: // http://cache.freescale.com/files/sensors/doc/app_note/AN3461.pdf?fpsp=1 // Heading calculations taken from this app note: // http://www51.honeywell.com/aero/common/documents/myaerospacecatalog-documents/Defense_Brochures-documents/Magnetic__Literature_Application_notes-documents/AN203_Compass_Heading_Using_Magnetometers.pdf void printAttitude(float ax, float ay, float az, float mx, float my, float mz) { float roll = atan2(ay, az); float pitch = atan2(-ax, sqrt(ay * ay + az * az)); // touchy trig stuff to use arctan to get compass heading (scale is 0..360) mx = -mx; float heading; if (my == 0.0) heading = (mx < 0.0) ? 180.0 : 0.0; else heading = atan2(mx, my)*360.0/(2.0*PI); //pc.printf("heading atan=%f \n\r",heading); heading -= DECLINATION; //correct for geo location if(heading>180.0) heading = heading - 360.0; else if(heading<-180.0) heading = 360.0 + heading; else if(heading<0.0) heading = 360.0 + heading; // Convert everything from radians to degrees: //heading *= 180.0 / PI; pitch *= 180.0 / PI; roll *= 180.0 / PI; pc.printf("Pitch: %f, Roll: %f degress\n\r",pitch,roll); pc.printf("Magnetic Heading: %f degress\n\r",heading); } int main() { // basic printf demo = 16 by 18 characters on screen //LSM9DS1 lol(p9, p10, 0x6B, 0x1E); LSM9DS1 IMU(p28, p27, 0xD6, 0x3C); IMU.begin(); if (!IMU.begin()) { pc.printf("Failed to communicate with LSM9DS1.\n"); } IMU.calibrate(1); IMU.calibrateMag(0); while(1) { while(!IMU.tempAvailable()); IMU.readTemp(); while(!IMU.magAvailable(X_AXIS)); IMU.readMag(); while(!IMU.accelAvailable()); IMU.readAccel(); while(!IMU.gyroAvailable()); IMU.readGyro(); pc.printf("\nIMU Temperature = %f C\n\r",25.0 + IMU.temperature/16.0); pc.printf(" X axis Y axis Z axis\n\r"); pc.printf("gyro: %9f %9f %9f in deg/s\n\r", IMU.calcGyro(IMU.gx), IMU.calcGyro(IMU.gy), IMU.calcGyro(IMU.gz)); pc.printf("accel: %9f %9f %9f in Gs\n\r", IMU.calcAccel(IMU.ax), IMU.calcAccel(IMU.ay), IMU.calcAccel(IMU.az)); pc.printf("mag: %9f %9f %9f in gauss\n\r", IMU.calcMag(IMU.mx), IMU.calcMag(IMU.my), IMU.calcMag(IMU.mz)); printAttitude(IMU.calcAccel(IMU.ax), IMU.calcAccel(IMU.ay), IMU.calcAccel(IMU.az), IMU.calcMag(IMU.mx), IMU.calcMag(IMU.my), IMU.calcMag(IMU.mz)); myled = 1; wait(2.5); myled = 0; wait(0.5); while(1) { while(!IMU.accelAvailable()); IMU.readAccel(); accel_x = IMU.calcAccel(IMU.ax); accel_y = IMU.calcAccel(IMU.ay); accel_z = IMU.calcAccel(IMU.az); pc.printf("accel: %9f %9f %9f in Gs\n\r", IMU.calcAccel(IMU.ax), IMU.calcAccel(IMU.ay), IMU.calcAccel(IMU.az)); //draw ball x = 64 + 64*accel_x; y = 64 + 64*accel_y; uLCD.circle(64, 64, outer_radius, RED); uLCD.filled_circle(x,y, radius, BLUE); //bounce off edge walls and slow down a bit? // if ((x<=radius+1) || (x>=126-radius)) vx = -.90*vx; // if ((y<=radius+1) || (y>=126-radius)) vy = -.90*vy; //erase old ball location // uLCD.filled_circle(x, y, radius, BLACK); //move ball // fx=fx+vx; // fy=fy+vy; // x=(int)fx; // y=(int)fy; wait(0.1); uLCD.filled_circle(x,y, radius, BLACK); } } }