ardupilot/libraries/AP_Compass/Compass.h

140 lines
4.5 KiB
C++

/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
#ifndef Compass_h
#define Compass_h
#include <inttypes.h>
#include "../AP_Common/AP_Common.h"
#include "../AP_Math/AP_Math.h"
#include "../AP_Declination/AP_Declination.h" // ArduPilot Mega Declination Helper Library
// compass product id
#define AP_COMPASS_TYPE_UNKNOWN 0x00
#define AP_COMPASS_TYPE_HIL 0x01
#define AP_COMPASS_TYPE_HMC5843 0x02
#define AP_COMPASS_TYPE_HMC5883L 0x03
class Compass
{
public:
int16_t product_id; /// product id
int16_t mag_x; ///< magnetic field strength along the X axis
int16_t mag_y; ///< magnetic field strength along the Y axis
int16_t mag_z; ///< magnetic field strength along the Z axis
uint32_t last_update; ///< micros() time of last update
bool healthy; ///< true if last read OK
/// Constructor
///
Compass();
/// Initialize the compass device.
///
/// @returns True if the compass was initialized OK, false if it was not
/// found or is not functioning.
///
virtual bool init();
/// Read the compass and update the mag_ variables.
///
virtual bool read(void) = 0;
/// use spare CPU cycles to accumulate values from the compass if
/// possible
virtual void accumulate(void) = 0;
/// Calculate the tilt-compensated heading_ variables.
///
/// @param roll The current airframe roll angle.
/// @param pitch The current airframe pitch angle.
///
/// @returns heading in radians
///
virtual float calculate_heading(float roll, float pitch);
/// Calculate the tilt-compensated heading_ variables.
///
/// @param dcm_matrix The current orientation rotation matrix
///
/// @returns heading in radians
///
virtual float calculate_heading(const Matrix3f &dcm_matrix);
/// Set the compass orientation matrix, used to correct for
/// various compass mounting positions.
///
/// @param rotation_matrix Rotation matrix to transform magnetometer readings
/// to the body frame.
///
virtual void set_orientation(enum Rotation rotation);
/// Sets the compass offset x/y/z values.
///
/// @param offsets Offsets to the raw mag_ values.
///
virtual void set_offsets(const Vector3f &offsets);
/// Saves the current compass offset x/y/z values.
///
/// This should be invoked periodically to save the offset values maintained by
/// ::null_offsets.
///
virtual void save_offsets();
/// Returns the current offset values
///
/// @returns The current compass offsets.
///
virtual Vector3f &get_offsets();
/// Sets the initial location used to get declination
///
/// @param latitude GPS Latitude.
/// @param longitude GPS Longitude.
///
void set_initial_location(int32_t latitude, int32_t longitude);
/// Program new offset values.
///
/// @param x Offset to the raw mag_x value.
/// @param y Offset to the raw mag_y value.
/// @param z Offset to the raw mag_z value.
///
void set_offsets(int x, int y, int z) {
set_offsets(Vector3f(x, y, z));
}
/// Perform automatic offset updates
///
void null_offsets(void);
/// return true if the compass should be used for yaw calculations
bool use_for_yaw(void) {
return healthy && _use_for_yaw;
}
/// Sets the local magnetic field declination.
///
/// @param radians Local field declination.
///
virtual void set_declination(float radians);
float get_declination();
static const struct AP_Param::GroupInfo var_info[];
protected:
enum Rotation _orientation;
AP_Vector3f _offset;
AP_Float _declination;
AP_Int8 _learn; ///<enable calibration learning
AP_Int8 _use_for_yaw; ///<enable use for yaw calculation
AP_Int8 _auto_declination; ///<enable automatic declination code
bool _null_init_done; ///< first-time-around flag used by offset nulling
///< used by offset correction
static const uint8_t _mag_history_size = 20;
uint8_t _mag_history_index;
Vector3i _mag_history[_mag_history_size];
};
#endif