AP_InertialNav.h

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#pragma once

#include <AP_AHRS/AP_AHRS.h>
#include <AP_InertialSensor/AP_InertialSensor.h>          // ArduPilot Mega IMU Library
#include <AP_Baro/AP_Baro.h>                    // ArduPilot Mega Barometer Library
#include <AP_Buffer/AP_Buffer.h>                  // FIFO buffer library
#include <AP_NavEKF/AP_Nav_Common.h> // definitions shared by inertial and ekf nav filters

/*
 * AP_InertialNav blends accelerometer data with gps and barometer data to improve altitude and position hold.
 *
 * Most of the functions have to be called at 100Hz. (see defines above)
 *
 * The accelerometer values are integrated over time to approximate velocity and position.
 * The inaccurcy of these estimates grows over time due to noisy sensor data.
 * To improve the accuracy, baro and gps readings are used:
 *      An error value is calculated as the difference between the sensor's measurement and the last position estimation.
 *      This value is weighted with a gain factor and incorporated into the new estimation
 *
 * Special thanks to Tony Lambregts (FAA) for advice which contributed to the development of this filter.
 *
 */
class AP_InertialNav
{
public:

    // Constructor
    AP_InertialNav() {}

    virtual void update(float dt) = 0;

    virtual nav_filter_status get_filter_status() const = 0;

    virtual struct Location get_origin() const = 0;

    //
    // XY Axis specific methods
    //

    virtual const Vector3f&    get_position() const = 0;

    virtual bool get_location(struct Location &loc) const = 0;

    virtual int32_t     get_latitude() const = 0;

    virtual int32_t     get_longitude() const = 0;

    virtual const Vector3f&    get_velocity() const = 0;

    virtual float get_velocity_xy() const = 0;

    //
    // Z Axis methods
    //

    virtual float       get_altitude() const = 0;

    virtual float       get_velocity_z() const = 0;
};

#if AP_AHRS_NAVEKF_AVAILABLE
#include "AP_InertialNav_NavEKF.h"
#endif