/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*- #ifndef __AP_INERTIAL_SENSOR_H__ #define __AP_INERTIAL_SENSOR_H__ // Gyro and Accelerometer calibration criteria #define AP_INERTIAL_SENSOR_ACCEL_TOT_MAX_OFFSET_CHANGE 4.0f #define AP_INERTIAL_SENSOR_ACCEL_MAX_OFFSET 250.0f #include #include #include #include "AP_InertialSensor_UserInteract.h" /* AP_InertialSensor is an abstraction for gyro and accel measurements * which are correctly aligned to the body axes and scaled to SI units. * * Gauss-Newton accel calibration routines borrowed from Rolfe Schmidt * blog post describing the method: http://chionophilous.wordpress.com/2011/10/24/accelerometer-calibration-iv-1-implementing-gauss-newton-on-an-atmega/ * original sketch available at http://rolfeschmidt.com/mathtools/skimetrics/adxl_gn_calibration.pde */ class AP_InertialSensor { public: AP_InertialSensor(); enum Start_style { COLD_START = 0, WARM_START }; // the rate that updates will be available to the application enum Sample_rate { RATE_50HZ, RATE_100HZ, RATE_200HZ }; /// Perform startup initialisation. /// /// Called to initialise the state of the IMU. /// /// For COLD_START, implementations using real sensors can assume /// that the airframe is stationary and nominally oriented. /// /// For WARM_START, no assumptions should be made about the /// orientation or motion of the airframe. Calibration should be /// as for the previous COLD_START call. /// /// @param style The initialisation startup style. /// virtual void init( Start_style style, Sample_rate sample_rate); /// Perform cold startup initialisation for just the accelerometers. /// /// @note This should not be called unless ::init has previously /// been called, as ::init may perform other work. /// virtual void init_accel(); #if !defined( __AVR_ATmega1280__ ) // perform accelerometer calibration including providing user instructions // and feedback virtual bool calibrate_accel(AP_InertialSensor_UserInteract *interact, float& trim_roll, float& trim_pitch); #endif /// calibrated - returns true if the accelerometers have been calibrated /// /// @note this should not be called while flying because it reads from the eeprom which can be slow /// bool calibrated(); /// Perform cold-start initialisation for just the gyros. /// /// @note This should not be called unless ::init has previously /// been called, as ::init may perform other work /// virtual void init_gyro(void); /// Fetch the current gyro values /// /// @returns vector of rotational rates in radians/sec /// Vector3f get_gyro(void) const { return _gyro; } void set_gyro(Vector3f gyro) { _gyro = gyro; } // set gyro offsets in radians/sec Vector3f get_gyro_offsets(void) { return _gyro_offset; } void set_gyro_offsets(Vector3f offsets) { _gyro_offset.set(offsets); } /// Fetch the current accelerometer values /// /// @returns vector of current accelerations in m/s/s /// Vector3f get_accel(void) const { return _accel; } void set_accel(Vector3f accel) { _accel = accel; } // get accel offsets in m/s/s Vector3f get_accel_offsets() { return _accel_offset; } void set_accel_offsets(Vector3f offsets) { _accel_offset.set(offsets); } // get accel scale Vector3f get_accel_scale() { return _accel_scale; } /* Update the sensor data, so that getters are nonblocking. * Returns a bool of whether data was updated or not. */ virtual bool update() = 0; /* get_delta_time returns the time period in seconds * overwhich the sensor data was collected */ virtual float get_delta_time() = 0; // return the maximum gyro drift rate in radians/s/s. This // depends on what gyro chips are being used virtual float get_gyro_drift_rate(void) = 0; // get number of samples read from the sensors virtual uint16_t num_samples_available() = 0; // class level parameters static const struct AP_Param::GroupInfo var_info[]; // set overall board orientation void set_board_orientation(enum Rotation orientation) { _board_orientation = orientation; } // override default filter frequency void set_default_filter(float filter_hz) { if (!_mpu6000_filter.load()) { _mpu6000_filter.set(filter_hz); } } protected: // sensor specific init to be overwritten by descendant classes virtual uint16_t _init_sensor( Sample_rate sample_rate ) = 0; // no-save implementations of accel and gyro initialisation routines virtual void _init_accel(); virtual void _init_gyro(); #if !defined( __AVR_ATmega1280__ ) // Calibration routines borrowed from Rolfe Schmidt // blog post describing the method: http://chionophilous.wordpress.com/2011/10/24/accelerometer-calibration-iv-1-implementing-gauss-newton-on-an-atmega/ // original sketch available at http://rolfeschmidt.com/mathtools/skimetrics/adxl_gn_calibration.pde // _calibrate_accel - perform low level accel calibration virtual bool _calibrate_accel(Vector3f accel_sample[6], Vector3f& accel_offsets, Vector3f& accel_scale); virtual void _calibrate_update_matrices(float dS[6], float JS[6][6], float beta[6], float data[3]); virtual void _calibrate_reset_matrices(float dS[6], float JS[6][6]); virtual void _calibrate_find_delta(float dS[6], float JS[6][6], float delta[6]); virtual void _calculate_trim(Vector3f accel_sample, float& trim_roll, float& trim_pitch); #endif // save parameters to eeprom void _save_parameters(); // Most recent accelerometer reading obtained by ::update Vector3f _accel; // Most recent gyro reading obtained by ::update Vector3f _gyro; // product id AP_Int16 _product_id; // accelerometer scaling and offsets AP_Vector3f _accel_scale; AP_Vector3f _accel_offset; AP_Vector3f _gyro_offset; // filtering frequency (0 means default) AP_Int8 _mpu6000_filter; // board orientation from AHRS enum Rotation _board_orientation; }; #include "AP_InertialSensor_Oilpan.h" #include "AP_InertialSensor_MPU6000.h" #include "AP_InertialSensor_Stub.h" #include "AP_InertialSensor_PX4.h" #include "AP_InertialSensor_UserInteract_Stream.h" #include "AP_InertialSensor_UserInteract_MAVLink.h" #endif // __AP_INERTIAL_SENSOR_H__