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Indoor/sensors/imu/CompassDetection.h
frank 857d7a1553 fixed some issues
added new pose/turn detections
new helper classes
define-flags for libEigen
2018-09-04 10:49:00 +02:00

141 lines
4.0 KiB
C++

#ifndef INDOOR_IMU_COMPASSDETECTION_H
#define INDOOR_IMU_COMPASSDETECTION_H
#include "MagnetometerData.h"
#include "PoseProvider.h"
#include "TurnProvider.h"
#include "../../data/Timestamp.h"
#include "../../math/MovingAverageTS.h"
#include "../../math/MovingStdDevTS.h"
#include "../../geo/Point3.h"
#include "../../Assertions.h"
#include "../../geo/Angle.h"
#include "CompassDetectionPlot.h"
#include <cmath>
#include <vector>
#include "../../math/dsp/iir/BiQuad.h"
/**
* custom compass implementation, similar to turn-detection
*/
class CompassDetection {
private:
#ifdef WITH_DEBUG_PLOT
CompassDetectionPlot plot;
#endif
// struct {
// Eigen::Matrix3f rotationMatrix = Eigen::Matrix3f::Identity();
// bool isKnown = false;
// Timestamp lastEstimation;
// } orientation;
MovingAverageTS<MagnetometerData> avgIn;
//MovingStdDevTS<MagnetometerData> stdDev = MovingStdDevTS<MagnetometerData>(Timestamp::fromMS(2000), MagnetometerData(0,0,0));
MovingStdDevTS<float> stdDev = MovingStdDevTS<float>(Timestamp::fromMS(1500), 0);
const PoseProvider* pose = nullptr;
const TurnProvider* turn = nullptr;
int numMagReadings = 0;
bool stable;
MovingStdDevTS<float> stdDevForSigma = MovingStdDevTS<float>(Timestamp::fromMS(500), 0);
float lastHeading = 0;
float curSigma = 0;
public:
/** ctor */
CompassDetection(const PoseProvider* pose, const TurnProvider* turn, const Timestamp avgFrame = Timestamp::fromMS(500)) :
pose(pose), turn(turn), avgIn(avgFrame, MagnetometerData(0,0,0)) {
;
}
/** get the current uncertainty estimation */
float getSigma() {
return curSigma + pose->getSigma() + turn->getSigma();
}
/** add magnetometer readings, returns the current heading, or NAN (if unstable/unknown) */
float addMagnetometer(const Timestamp& ts, const MagnetometerData& mag) {
++numMagReadings;
// get the current magnetometer-reading as vector
//Eigen::Vector3f vec; vec << mag.x, mag.y, mag.z;
const Vector3 vec(mag.x, mag.y, mag.z);
// rotate it into our desired coordinate system, where the smartphone lies flat on the ground
//Eigen::Vector3f _curMag = pose->getMatrix() * vec;
const Vector3 _curMag = pose->getMatrix() * vec;
//avgIn.add(ts, MagnetometerData(_curMag(0), _curMag(1), _curMag(2)));
avgIn.add(ts, MagnetometerData(_curMag.x, _curMag.y, _curMag.z));
const MagnetometerData curMag = avgIn.get();
//const MagnetometerData curMag =MagnetometerData(_curMag.x, _curMag.y, _curMag.z);
// calculate standard-deviation
//stdDev.add(ts, curMag);
//const float dev = std::max(stdDev.get().x, stdDev.get().y);
// calculate angle
// https://aerocontent.honeywell.com/aero/common/documents/myaerospacecatalog-documents/Defense_Brochures-documents/Magnetic__Literature_Application_notes-documents/AN203_Compass_Heading_Using_Magnetometers.pdf
const float mx = (curMag.x);
const float my = (curMag.y);
const float tmp = std::atan2(my, mx);
//const float tmp = (my > 0) ? (M_PI*0.5 - std::atan(mx/my)) : (M_PI*1.5 - atan(mx/my));
// http://www.magnetic-declination.com/
// http://davidegironi.blogspot.de/2013/01/avr-atmega-hmc5883l-magnetometer-lib-01.html
const float declination = 3.0f / 180.0f * M_PI; // GERMANY!
//const float declination = 0; // GERMANY!
float curHeading = Angle::makeSafe_2PI(- tmp + declination);
float resHeading;
stable = true;
// calculate standard-deviation within a certain timeframe
const float curDiff = Angle::getSignedDiffRAD_2PI(curHeading, lastHeading);
stdDev.add(ts, curDiff);
stdDevForSigma.add(ts, curDiff);
curSigma = (5.0f/180.0f*(float)M_PI) + stdDevForSigma.get()*10;
lastHeading = curHeading;
// if the standard-deviation is too high,
// the compass is considered unstable
// if (numMagReadings < 250 || stdDev.get() > 0.30) {
// resHeading = NAN;
// stable = false;
// } else {
resHeading = curHeading;
stable = true;
// }
#ifdef WITH_DEBUG_PLOT
plot.add(ts, curHeading, stable, mag, curMag);
#endif
// done
return resHeading;
}
};
#endif // INDOOR_IMU_COMPASSDETECTION_H