#define AP_INLINE_VECTOR_OPS #include #include "AP_InertialSensor.h" #include "AP_InertialSensor_Backend.h" #include #include #if AP_MODULE_SUPPORTED #include #endif #include #define SENSOR_RATE_DEBUG 0 #ifndef AP_HEATER_IMU_INSTANCE #define AP_HEATER_IMU_INSTANCE 0 #endif const extern AP_HAL::HAL& hal; AP_InertialSensor_Backend::AP_InertialSensor_Backend(AP_InertialSensor &imu) : _imu(imu) { } /* notify of a FIFO reset so we don't use bad data to update observed sensor rate */ void AP_InertialSensor_Backend::notify_accel_fifo_reset(uint8_t instance) { _imu._sample_accel_count[instance] = 0; _imu._sample_accel_start_us[instance] = 0; } /* notify of a FIFO reset so we don't use bad data to update observed sensor rate */ void AP_InertialSensor_Backend::notify_gyro_fifo_reset(uint8_t instance) { _imu._sample_gyro_count[instance] = 0; _imu._sample_gyro_start_us[instance] = 0; } // set the amount of oversamping a accel is doing void AP_InertialSensor_Backend::_set_accel_oversampling(uint8_t instance, uint8_t n) { _imu._accel_over_sampling[instance] = n; } // set the amount of oversamping a gyro is doing void AP_InertialSensor_Backend::_set_gyro_oversampling(uint8_t instance, uint8_t n) { _imu._gyro_over_sampling[instance] = n; } /* update the sensor rate for FIFO sensors FIFO sensors produce samples at a fixed rate, but the clock in the sensor may vary slightly from the system clock. This slowly adjusts the rate to the observed rate */ void AP_InertialSensor_Backend::_update_sensor_rate(uint16_t &count, uint32_t &start_us, float &rate_hz) const { uint32_t now = AP_HAL::micros(); if (start_us == 0) { count = 0; start_us = now; } else { count++; if (now - start_us > 1000000UL) { float observed_rate_hz = count * 1.0e6f / (now - start_us); #if 0 printf("IMU RATE: %.1f should be %.1f\n", observed_rate_hz, rate_hz); #endif float filter_constant = 0.98f; float upper_limit = 1.05f; float lower_limit = 0.95f; if (sensors_converging()) { // converge quickly for first 30s, then more slowly filter_constant = 0.8f; upper_limit = 2.0f; lower_limit = 0.5f; } observed_rate_hz = constrain_float(observed_rate_hz, rate_hz*lower_limit, rate_hz*upper_limit); rate_hz = filter_constant * rate_hz + (1-filter_constant) * observed_rate_hz; count = 0; start_us = now; } } } void AP_InertialSensor_Backend::_rotate_and_correct_accel(uint8_t instance, Vector3f &accel) { /* accel calibration is always done in sensor frame with this version of the code. That means we apply the rotation after the offsets and scaling. */ // rotate for sensor orientation accel.rotate(_imu._accel_orientation[instance]); #if HAL_INS_TEMPERATURE_CAL_ENABLE if (_imu.tcal_learning) { _imu.tcal(instance).update_accel_learning(accel, _imu.get_temperature(instance)); } #endif if (!_imu._calibrating_accel && (_imu._acal == nullptr #if HAL_INS_ACCELCAL_ENABLED || !_imu._acal->running() #endif )) { #if HAL_INS_TEMPERATURE_CAL_ENABLE // apply temperature corrections _imu.tcal(instance).correct_accel(_imu.get_temperature(instance), _imu.caltemp_accel(instance), accel); #endif // apply offsets accel -= _imu._accel_offset(instance); // apply scaling const Vector3f &accel_scale = _imu._accel_scale(instance).get(); accel.x *= accel_scale.x; accel.y *= accel_scale.y; accel.z *= accel_scale.z; } // rotate to body frame accel.rotate(_imu._board_orientation); } void AP_InertialSensor_Backend::_rotate_and_correct_gyro(uint8_t instance, Vector3f &gyro) { // rotate for sensor orientation gyro.rotate(_imu._gyro_orientation[instance]); #if HAL_INS_TEMPERATURE_CAL_ENABLE if (_imu.tcal_learning) { _imu.tcal(instance).update_gyro_learning(gyro, _imu.get_temperature(instance)); } #endif if (!_imu._calibrating_gyro) { #if HAL_INS_TEMPERATURE_CAL_ENABLE // apply temperature corrections _imu.tcal(instance).correct_gyro(_imu.get_temperature(instance), _imu.caltemp_gyro(instance), gyro); #endif // gyro calibration is always assumed to have been done in sensor frame gyro -= _imu._gyro_offset(instance); } gyro.rotate(_imu._board_orientation); } /* rotate gyro vector and add the gyro offset */ void AP_InertialSensor_Backend::_publish_gyro(uint8_t instance, const Vector3f &gyro) /* front end */ { if ((1U< 0) { Vector3f scaled_gyro = gyro * _imu._gyro_raw_sampling_multiplier[instance]; // LPF always must come last to remove high-frequency shot noise, but the FFT still // needs to see the same data so gets its own LPF at the tap point if (_imu._post_filter_fft) { scaled_gyro = _imu._post_filter_gyro_filter[instance].apply(scaled_gyro); } _imu._gyro_window[instance][0].push(scaled_gyro.x); _imu._gyro_window[instance][1].push(scaled_gyro.y); _imu._gyro_window[instance][2].push(scaled_gyro.z); _imu._last_gyro_for_fft[instance] = scaled_gyro; } else { _imu._last_gyro_for_fft[instance] = gyro * _imu._gyro_raw_sampling_multiplier[instance];; } } #endif } /* apply harmonic notch and low pass gyro filters */ void AP_InertialSensor_Backend::apply_gyro_filters(const uint8_t instance, const Vector3f &gyro) { uint8_t filter_phase = 0; save_gyro_window(instance, gyro, filter_phase++); Vector3f gyro_filtered = gyro; // apply the harmonic notch filters for (auto ¬ch : _imu.harmonic_notches) { if (!notch.params.enabled()) { continue; } bool inactive = notch.is_inactive(); #ifndef HAL_BUILD_AP_PERIPH // by default we only run the expensive notch filters on the // currently active IMU we reset the inactive notch filters so // that if we switch IMUs we're not left with old data if (!notch.params.hasOption(HarmonicNotchFilterParams::Options::EnableOnAllIMUs) && instance != AP::ahrs().get_primary_gyro_index()) { inactive = true; } #endif if (inactive) { // while inactive we reset the filter so when it activates the first output // will be the first input sample notch.filter[instance].reset(); } else { gyro_filtered = notch.filter[instance].apply(gyro_filtered); } save_gyro_window(instance, gyro_filtered, filter_phase++); } // apply the low pass filter last to attenuate any notch induced noise gyro_filtered = _imu._gyro_filter[instance].apply(gyro_filtered); // if the filtering failed in any way then reset the filters and keep the old value if (gyro_filtered.is_nan() || gyro_filtered.is_inf()) { _imu._gyro_filter[instance].reset(); #if HAL_WITH_DSP _imu._post_filter_gyro_filter[instance].reset(); #endif for (auto ¬ch : _imu.harmonic_notches) { notch.filter[instance].reset(); } } else { _imu._gyro_filtered[instance] = gyro_filtered; } } void AP_InertialSensor_Backend::_notify_new_gyro_raw_sample(uint8_t instance, const Vector3f &gyro, uint64_t sample_us) { if ((1U<push_gyro(gyro.x, gyro.y, dt); } // compute delta angle Vector3f delta_angle = (gyro + _imu._last_raw_gyro[instance]) * 0.5f * dt; // compute coning correction // see page 26 of: // Tian et al (2010) Three-loop Integration of GPS and Strapdown INS with Coning and Sculling Compensation // Available: http://www.sage.unsw.edu.au/snap/publications/tian_etal2010b.pdf // see also examples/coning.py Vector3f delta_coning = (_imu._delta_angle_acc[instance] + _imu._last_delta_angle[instance] * (1.0f / 6.0f)); delta_coning = delta_coning % delta_angle; delta_coning *= 0.5f; { WITH_SEMAPHORE(_sem); uint64_t now = AP_HAL::micros64(); if (now - last_sample_us > 100000U) { // zero accumulator if sensor was unhealthy for 0.1s _imu._delta_angle_acc[instance].zero(); _imu._delta_angle_acc_dt[instance] = 0; dt = 0; delta_angle.zero(); } // integrate delta angle accumulator // the angles and coning corrections are accumulated separately in the // referenced paper, but in simulation little difference was found between // integrating together and integrating separately (see examples/coning.py) _imu._delta_angle_acc[instance] += delta_angle + delta_coning; _imu._delta_angle_acc_dt[instance] += dt; // save previous delta angle for coning correction _imu._last_delta_angle[instance] = delta_angle; _imu._last_raw_gyro[instance] = gyro; // apply gyro filters and sample for FFT apply_gyro_filters(instance, gyro); _imu._new_gyro_data[instance] = true; } // 5us #if AP_INERTIALSENSOR_BATCHSAMPLER_ENABLED if (!_imu.batchsampler.doing_post_filter_logging()) { log_gyro_raw(instance, sample_us, gyro); } else { log_gyro_raw(instance, sample_us, _imu._gyro_filtered[instance]); } #else // assume pre-filter logging if batchsampler is not enabled log_gyro_raw(instance, sample_us, gyro); #endif } /* handle a delta-angle sample from the backend. This assumes FIFO style sampling and the sample should not be rotated or corrected for offsets. This function should be used when the sensor driver can directly provide delta-angle values from the sensor. */ void AP_InertialSensor_Backend::_notify_new_delta_angle(uint8_t instance, const Vector3f &dangle) { if ((1U<push_gyro(gyro.x, gyro.y, dt); } // compute delta angle, including corrections Vector3f delta_angle = gyro * dt; // compute coning correction // see page 26 of: // Tian et al (2010) Three-loop Integration of GPS and Strapdown INS with Coning and Sculling Compensation // Available: http://www.sage.unsw.edu.au/snap/publications/tian_etal2010b.pdf // see also examples/coning.py Vector3f delta_coning = (_imu._delta_angle_acc[instance] + _imu._last_delta_angle[instance] * (1.0f / 6.0f)); delta_coning = delta_coning % delta_angle; delta_coning *= 0.5f; { WITH_SEMAPHORE(_sem); uint64_t now = AP_HAL::micros64(); if (now - last_sample_us > 100000U) { // zero accumulator if sensor was unhealthy for 0.1s _imu._delta_angle_acc[instance].zero(); _imu._delta_angle_acc_dt[instance] = 0; dt = 0; delta_angle.zero(); } // integrate delta angle accumulator // the angles and coning corrections are accumulated separately in the // referenced paper, but in simulation little difference was found between // integrating together and integrating separately (see examples/coning.py) _imu._delta_angle_acc[instance] += delta_angle + delta_coning; _imu._delta_angle_acc_dt[instance] += dt; // save previous delta angle for coning correction _imu._last_delta_angle[instance] = delta_angle; _imu._last_raw_gyro[instance] = gyro; // apply gyro filters and sample for FFT apply_gyro_filters(instance, gyro); _imu._new_gyro_data[instance] = true; } #if AP_INERTIALSENSOR_BATCHSAMPLER_ENABLED if (!_imu.batchsampler.doing_post_filter_logging()) { log_gyro_raw(instance, sample_us, gyro); } else { log_gyro_raw(instance, sample_us, _imu._gyro_filtered[instance]); } #else // assume we're doing pre-filter logging: log_gyro_raw(instance, sample_us, gyro); #endif } void AP_InertialSensor_Backend::log_gyro_raw(uint8_t instance, const uint64_t sample_us, const Vector3f &gyro) { #if HAL_LOGGING_ENABLED AP_Logger *logger = AP_Logger::get_singleton(); if (logger == nullptr) { // should not have been called return; } if (should_log_imu_raw()) { Write_GYR(instance, sample_us, gyro); } else { #if AP_INERTIALSENSOR_BATCHSAMPLER_ENABLED if (!_imu.batchsampler.doing_sensor_rate_logging()) { _imu.batchsampler.sample(instance, AP_InertialSensor::IMU_SENSOR_TYPE_GYRO, sample_us, gyro); } #endif } #endif } /* rotate accel vector, scale and add the accel offset */ void AP_InertialSensor_Backend::_publish_accel(uint8_t instance, const Vector3f &accel) /* front end */ { if ((1U< 100000U) { // zero accumulator if sensor was unhealthy for 0.1s _imu._delta_velocity_acc[instance].zero(); _imu._delta_velocity_acc_dt[instance] = 0; dt = 0; } // delta velocity _imu._delta_velocity_acc[instance] += accel * dt; _imu._delta_velocity_acc_dt[instance] += dt; _imu._accel_filtered[instance] = _imu._accel_filter[instance].apply(accel); if (_imu._accel_filtered[instance].is_nan() || _imu._accel_filtered[instance].is_inf()) { _imu._accel_filter[instance].reset(); } _imu.set_accel_peak_hold(instance, _imu._accel_filtered[instance]); _imu._new_accel_data[instance] = true; } // 5us #if AP_INERTIALSENSOR_BATCHSAMPLER_ENABLED if (!_imu.batchsampler.doing_post_filter_logging()) { log_accel_raw(instance, sample_us, accel); } else { log_accel_raw(instance, sample_us, _imu._accel_filtered[instance]); } #else // assume we're doing pre-filter logging: log_accel_raw(instance, sample_us, accel); #endif } /* handle a delta-velocity sample from the backend. This assumes FIFO style sampling and the sample should not be rotated or corrected for offsets This function should be used when the sensor driver can directly provide delta-velocity values from the sensor. */ void AP_InertialSensor_Backend::_notify_new_delta_velocity(uint8_t instance, const Vector3f &dvel) { if ((1U< 100000U) { // zero accumulator if sensor was unhealthy for 0.1s _imu._delta_velocity_acc[instance].zero(); _imu._delta_velocity_acc_dt[instance] = 0; dt = 0; } // delta velocity including corrections _imu._delta_velocity_acc[instance] += accel * dt; _imu._delta_velocity_acc_dt[instance] += dt; _imu._accel_filtered[instance] = _imu._accel_filter[instance].apply(accel); if (_imu._accel_filtered[instance].is_nan() || _imu._accel_filtered[instance].is_inf()) { _imu._accel_filter[instance].reset(); } _imu.set_accel_peak_hold(instance, _imu._accel_filtered[instance]); _imu._new_accel_data[instance] = true; } #if AP_INERTIALSENSOR_BATCHSAMPLER_ENABLED if (!_imu.batchsampler.doing_post_filter_logging()) { log_accel_raw(instance, sample_us, accel); } else { log_accel_raw(instance, sample_us, _imu._accel_filtered[instance]); } #else // assume we're doing pre-filter logging log_accel_raw(instance, sample_us, accel); #endif } void AP_InertialSensor_Backend::_notify_new_accel_sensor_rate_sample(uint8_t instance, const Vector3f &accel) { #if AP_INERTIALSENSOR_BATCHSAMPLER_ENABLED if (!_imu.batchsampler.doing_sensor_rate_logging()) { return; } _imu.batchsampler.sample(instance, AP_InertialSensor::IMU_SENSOR_TYPE_ACCEL, AP_HAL::micros64(), accel); #endif } void AP_InertialSensor_Backend::_notify_new_gyro_sensor_rate_sample(uint8_t instance, const Vector3f &gyro) { #if AP_INERTIALSENSOR_BATCHSAMPLER_ENABLED if (!_imu.batchsampler.doing_sensor_rate_logging()) { return; } _imu.batchsampler.sample(instance, AP_InertialSensor::IMU_SENSOR_TYPE_GYRO, AP_HAL::micros64(), gyro); #endif } void AP_InertialSensor_Backend::log_accel_raw(uint8_t instance, const uint64_t sample_us, const Vector3f &accel) { #if HAL_LOGGING_ENABLED AP_Logger *logger = AP_Logger::get_singleton(); if (logger == nullptr) { // should not have been called return; } if (should_log_imu_raw()) { Write_ACC(instance, sample_us, accel); } else { #if AP_INERTIALSENSOR_BATCHSAMPLER_ENABLED if (!_imu.batchsampler.doing_sensor_rate_logging()) { _imu.batchsampler.sample(instance, AP_InertialSensor::IMU_SENSOR_TYPE_ACCEL, sample_us, accel); } #endif } #endif } void AP_InertialSensor_Backend::_set_accel_max_abs_offset(uint8_t instance, float max_offset) { _imu._accel_max_abs_offsets[instance] = max_offset; } // increment accelerometer error_count void AP_InertialSensor_Backend::_inc_accel_error_count(uint8_t instance) { _imu._accel_error_count[instance]++; } // increment gyro error_count void AP_InertialSensor_Backend::_inc_gyro_error_count(uint8_t instance) { _imu._gyro_error_count[instance]++; } /* publish a temperature value for an instance */ void AP_InertialSensor_Backend::_publish_temperature(uint8_t instance, float temperature) /* front end */ { if ((1U<set_imu_temp(temperature); } } #endif } /* common gyro update function for all backends */ void AP_InertialSensor_Backend::update_gyro(uint8_t instance) /* front end */ { WITH_SEMAPHORE(_sem); if ((1U<should_log(_imu._log_raw_bit)) { return false; } return true; } // log an unexpected change in a register for an IMU void AP_InertialSensor_Backend::log_register_change(uint32_t bus_id, const AP_HAL::Device::checkreg ®) { #if HAL_LOGGING_ENABLED AP::logger().Write("IREG", "TimeUS,DevID,Bank,Reg,Val", "QIBBB", AP_HAL::micros64(), bus_id, reg.bank, reg.regnum, reg.value); #endif }