uas-ugv/main/MadgwickAHRS.h

//=============================================================================================
// MadgwickAHRS.h
//=============================================================================================
//
// Implementation of Madgwick's IMU and AHRS algorithms.
// See: http://www.x-io.co.uk/open-source-imu-and-ahrs-algorithms/
//
// From the x-io website "Open-source resources available on this website are
// provided under the GNU General Public Licence unless an alternative licence
// is provided in source."
//
// Date			Author          Notes
// 29/09/2011	SOH Madgwick    Initial release
// 02/10/2011	SOH Madgwick	Optimised for reduced CPU load
//
//=============================================================================================
#ifndef MadgwickAHRS_h
#define MadgwickAHRS_h

#include <math.h>

//--------------------------------------------------------------------------------------------
// Variable declaration
class Madgwick {
 private:
  static float invSqrt(float x);

  float beta;  // algorithm gain
  float q0;
  float q1;
  float q2;
  float q3;  // quaternion of sensor frame relative to auxiliary frame
  float invSampleFreq;
  float roll;
  float pitch;
  float yaw;
  char anglesComputed;

  void computeAngles();

  //-------------------------------------------------------------------------------------------
  // Function declarations
 public:
  Madgwick(void);

  void begin(float sampleFrequency) { invSampleFreq = 1.0f / sampleFrequency; }

  void update(float gx, float gy, float gz, float ax, float ay, float az,
              float mx, float my, float mz);

  void updateIMU(float gx, float gy, float gz, float ax, float ay, float az);

  // float getPitch(){return atan2f(2.0f * q2 * q3 - 2.0f * q0 * q1, 2.0f * q0 *
  // q0 + 2.0f * q3 * q3 - 1.0f);}; float getRoll(){return -1.0f * asinf(2.0f *
  // q1 * q3 + 2.0f * q0 * q2);}; float getYaw(){return atan2f(2.0f * q1 * q2
  // - 2.0f * q0 * q3, 2.0f * q0 * q0 + 2.0f * q1 * q1 - 1.0f);};
  float getRoll() {
    if (!anglesComputed) computeAngles();
    return roll * 57.29578f;
  }

  float getPitch() {
    if (!anglesComputed) computeAngles();
    return pitch * 57.29578f;
  }

  float getYaw() {
    if (!anglesComputed) computeAngles();
    return yaw * 57.29578f + 180.0f;
  }

  float getRollRadians() {
    if (!anglesComputed) computeAngles();
    return roll;
  }

  float getPitchRadians() {
    if (!anglesComputed) computeAngles();
    return pitch;
  }

  float getYawRadians() {
    if (!anglesComputed) computeAngles();
    return yaw;
  }
};

#endif