Shuto Naruse
/
Eurobot2012_Secondary
Eurobot2012_Secondary
Fork of Eurobot_2012_Secondary by
Kalman/Kalman.cpp
- Committer:
- narshu
- Date:
- 2012-04-20
- Revision:
- 0:fbfafa6bf5f9
File content as of revision 0:fbfafa6bf5f9:
//*************************************************************************************** //Kalman Filter implementation //*************************************************************************************** #include "Kalman.h" #include "rtos.h" #include "RFSRF05.h" //#include "MatrixMath.h" //#include "Matrix.h" #include "math.h" #include "globals.h" #include "motors.h" #include "system.h" #include "geometryfuncs.h" #include <tvmet/Matrix.h> #include <tvmet/Vector.h> using namespace tvmet; DigitalOut led1(LED1); DigitalOut led2(LED2); DigitalOut led3(LED3); DigitalOut led4(LED4); Kalman::Kalman(Motors &motorsin) : sonararray(p10,p21,p22,p23,p24,p25,p26,p5,p6,p7,p8,p9), motors(motorsin), predictthread(predictloopwrapper, this, osPriorityNormal, 512), predictticker( SIGTICKARGS(predictthread, 0x1) ), // sonarthread(sonarloopwrapper, this, osPriorityNormal, 256), // sonarticker( SIGTICKARGS(sonarthread, 0x1) ), updatethread(updateloopwrapper, this, osPriorityNormal, 2048) { //Initilising matrices // X = x, y, theta; X = 0.5, 0, 0; P = 1, 0, 0, 0, 1, 0, 0, 0, 0.04; //Q = 0.002, 0, 0, //temporary matrix, Use dt! // 0, 0.002, 0, // 0, 0, 0.002; //measurment variance R is provided by each sensor when calling runupdate //attach callback sonararray.callbackobj = (DummyCT*)this; sonararray.mcallbackfunc = (void (DummyCT::*)(int beaconnum, float distance, float variance)) &Kalman::runupdate; predictticker.start(20); // sonarticker.start(50); } void Kalman::predictloop() { float lastleft = 0; float lastright = 0; while (1) { Thread::signal_wait(0x1); led1 = !led1; int leftenc = motors.getEncoder1(); int rightenc = motors.getEncoder2(); float dleft = motors.encoderToDistance(leftenc-lastleft)/1000.0f; float dright = motors.encoderToDistance(rightenc-lastright)/1000.0f; lastleft = leftenc; lastright = rightenc; //The below calculation are in body frame (where +x is forward) float dxp, dyp,d,r; float thetap = (dright - dleft)*PI / (float(robotCircumference)/1000.0f); if (abs(thetap) < 0.02) { //if the rotation through the integration step is small, approximate with a straight line to avoid numerical error d = (dright + dleft)/2.0f; dxp = d*cos(thetap/2.0f); dyp = d*sin(thetap/2.0f); } else { //calculate circle arc //float r = (right + left) / (4.0f * PI * thetap); r = (dright + dleft) / (2.0f*thetap); dxp = abs(r)*sin(thetap); dyp = r - r*cos(thetap); } statelock.lock(); //rotating to cartesian frame and updating state X(0) += dxp * cos(X(2)) - dyp * sin(X(2)); X(1) += dxp * sin(X(2)) + dyp * cos(X(2)); X(2) = rectifyAng(X(2) + thetap); //Linearising F around X Matrix<float, 3, 3> F; F = 1, 0, (dxp * -sin(X(2)) - dyp * cos(X(2))), 0, 1, (dxp * cos(X(2)) - dyp * sin(X(2))), 0, 0, 1; //Generating forward and rotational variance float varfwd = fwdvarperunit * (dright + dleft) / 2.0f; float varang = varperang * thetap; float varxydt = xyvarpertime * PREDICTPERIOD; float varangdt = angvarpertime * PREDICTPERIOD; //Rotating into cartesian frame Matrix<float, 2, 2> Qsub,Qsubrot,Qrot; Qsub = varfwd + varxydt, 0, 0, varxydt; Qrot = Rotmatrix(X(2)); Qsubrot = Qrot * Qsub * trans(Qrot); //Generate Q Matrix<float, 3, 3> Q;//(Qsubrot); Q = Qsubrot(0,0), Qsubrot(0,1), 0, Qsubrot(1,0), Qsubrot(1,1), 0, 0, 0, varang + varangdt; P = F * P * trans(F) + Q; statelock.unlock(); //Thread::wait(PREDICTPERIOD); //cout << "predict" << X << endl; //cout << P << endl; } } //void Kalman::sonarloop() { // while (1) { // Thread::signal_wait(0x1); // sonararray.startRange(); // } //} void Kalman::runupdate(measurement_t type, float value, float variance) { //printf("beacon %d dist %f\r\n", sonarid, dist); //led2 = !led2; measurmentdata* measured = (measurmentdata*)measureMQ.alloc(); if (measured) { measured->mtype = type; measured->value = value; measured->variance = variance; osStatus putret = measureMQ.put(measured); if (putret) led4 = 1; // printf("putting in MQ error code %#x\r\n", putret); } else { led4 = 1; //printf("MQalloc returned NULL ptr\r\n"); } } void Kalman::updateloop() { measurement_t type; float value,variance,rbx,rby,expecdist,Y; float dhdx,dhdy; bool aborton2stddev = false; Matrix<float, 1, 3> H; float S; Matrix<float, 3, 3> I3( identity< Matrix<float, 3, 3> >() ); while (1) { led2 = !led2; osEvent evt = measureMQ.get(); if (evt.status == osEventMail) { measurmentdata &measured = *(measurmentdata*)evt.value.p; type = measured.mtype; //Note, may support more measurment types than sonar in the future! value = measured.value; variance = measured.variance; // don't forget to free the memory measureMQ.free(&measured); if (type <= maxmeasure) { if (type <= SONAR3) { float dist = value / 1000.0f; //converting to m from mm int sonarid = type; aborton2stddev = false; statelock.lock(); SonarMeasures[sonarid] = dist; //update the current sonar readings rbx = X(0) - beaconpos[sonarid].x/1000.0f; rby = X(1) - beaconpos[sonarid].y/1000.0f; expecdist = hypot(rbx, rby);//sqrt(rbx*rbx + rby*rby); Y = dist - expecdist; dhdx = rbx / expecdist; dhdy = rby / expecdist; H = dhdx, dhdy, 0; } else if (type <= IR3) { aborton2stddev = false; int IRidx = type-3; statelock.lock(); IRMeasures[IRidx] = value; rbx = X(0) - beaconpos[IRidx].x/1000.0f; rby = X(1) - beaconpos[IRidx].y/1000.0f; float expecang = atan2(-rbx, -rby) - X(2); //printf("expecang: %0.4f, value: %0.4f \n\r", expecang*180/PI,value*180/PI); Y = rectifyAng(value + expecang); float dstsq = rbx*rbx + rby*rby; H = -rby/dstsq, rbx/dstsq, -1; } Matrix<float, 3, 1> PH (P * trans(H)); S = (H * PH)(0,0) + variance; if (aborton2stddev && Y*Y > 4 * S) { statelock.unlock(); continue; } Matrix<float, 3, 1> K (PH * (1/S)); //Updating state X += col(K, 0) * Y; X(2) = rectifyAng(X(2)); P = (I3 - K * H) * P; statelock.unlock(); } } else { led4 = 1; //printf("ERROR: in updateloop, code %#x", evt); } } }