Robot Position Control using IMU and Hall effect sensor
Dependencies: LSM9DS1_Library_cal Motordriver PID mbed
Fork of Lab4 by
main.cpp
- Committer:
- mmittal8
- Date:
- 2016-11-04
- Revision:
- 3:f41855c51aaf
- Parent:
- 1:4a490de4c2a4
File content as of revision 3:f41855c51aaf:
#include "mbed.h" #include "motordriver.h" //Library to drive motors #include "PID.h" //PID library for distance control #include "LSM9DS1.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. Motor LeftM(p21, p22, p23,1); // pwm, fwd, rev Motor RightM(p26, p27, p24,1); InterruptIn rhes(p15); InterruptIn lhes(p16); PID leftPid(1.0, 0.0, 0.0,0.01); //Kc, Ti, Td PID rightPid(1.0, 0.0, 0.0,0.01); //Kc, Ti, Td Serial pc(USBTX, USBRX); DigitalOut led1(LED1); DigitalOut led2(LED2); DigitalOut led3(LED3); LSM9DS1 IMU(p9, p10, 0xD6, 0x3C); PwmOut speaker(p25); int countl = 0, countr = 0; int xx=0,yy=0; float note1 = 1568.0, note2 = 1396.9, note3 = 1244.5; // 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 float getHeading(float mx, float my, float mz) { // 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); 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; heading = fabs(heading); return heading; } float getHead(){ while(!IMU.magAvailable(X_AXIS)); IMU.readMag(); return getHeading(IMU.calcMag(IMU.mx), IMU.calcMag(IMU.my), IMU.calcMag(IMU.mz)); } void leftM_count() { countl++; } void rightM_count() { countr++; } void move(float dist, int dir = 1){ led1 = 1; speaker.period(1.0/note1); speaker =0.25; wait(0.3); speaker.period(1.0/note2); wait(0.3); speaker=0.0; leftPid.setInputLimits(0, 1000); leftPid.setOutputLimits(0.0, 0.9); leftPid.setMode(AUTO_MODE); rightPid.setInputLimits(0, 1000); rightPid.setOutputLimits(0.0, 0.9); rightPid.setMode(AUTO_MODE); int leftPulses = 0; int leftPrevPulses = 0; float leftVelocity = 0.0; int rightPulses = 0; int rightPrevPulses = 0; float rightVelocity = 0.0; wait(1); leftPid.setSetPoint(750); rightPid.setSetPoint(750); while ((leftPulses < dist) || (rightPulses < dist)) { leftPulses = countl; leftVelocity = (leftPulses - leftPrevPulses) / 0.01; leftPrevPulses = leftPulses; leftPid.setProcessValue(leftVelocity); LeftM.speed(leftPid.compute()*dir); rightPulses = countr; rightVelocity = (rightPulses - rightPrevPulses) / 0.01; rightPrevPulses = rightPulses; rightPid.setProcessValue(rightVelocity); RightM.speed(rightPid.compute()*dir); wait(0.01); } countl = 0; countr = 0; RightM.speed(0); LeftM.speed(0); led1 = 0; wait(1); } void turn(int direction){ led2 = 1; speaker.period(1.0/note2); speaker =0.25; wait(0.3); speaker.period(1.0/note1); wait(0.3); speaker=0.0; float head = 0, oldHead = 0,newHead = 0; oldHead = getHead(); head = oldHead; //printf("Old Heading: %f\n\r", oldHead); if (direction == 1){ newHead = oldHead + 90; if (newHead > 360) newHead -= 360; } else{ newHead = oldHead - 90; if (newHead < 0) newHead += 360; } //printf("New Heading: %f\n\r", newHead); while ((head < newHead - 1) || (head > newHead + 1)){ if ((head < newHead && (newHead - head < 180)) || (head - newHead > 180)){ LeftM.speed(0.5); RightM.speed(-0.5); head = getHead(); //printf("heading: %f\n\r", head); wait(0.01); } else if ((head > newHead && (head-newHead < 180)) || (newHead - head > 180)){ LeftM.speed(-0.5); RightM.speed(0.5); head = getHead(); //printf("heading: %f\n\r", head); wait(0.01); } } LeftM.speed(0); RightM.speed(0); led2 = 0; countl = 0; countr = 0; wait(0.5); } void coord(int x, int y){ if (y>yy) move((y-yy)*250,1); else if (y<yy) move((yy-y)*250,-1); if (x>xx){ turn(1); move((x-xx)*250,1); turn(-1); } else if (x<xx){ turn(-1); move((xx-x)*250,1); turn(1); } xx=x; yy=y; } int main() { lhes.mode(PullUp); rhes.mode(PullUp); lhes.rise(&leftM_count); rhes.rise(&rightM_count); xx=0; yy=0; IMU.begin(); if (!IMU.begin()) { led1 = 1; led2 = 1; led3 = 1; } IMU.calibrate(1); led3 = 1; IMU.calibrateMag(0); led3 = 0; wait(2); // while (1){ // pc.printf("Heading: %f\n\r", getHead()); // wait (1); // } coord(0,2); coord(2,2); coord(2,0); coord(0,0); speaker.period(1.0/note3); speaker =0.25; wait(1); speaker=0.0; }