text: /****************************************************************************
   *
   *   Copyright (c) 2019 PX4 Development Team. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   * 3. Neither the name PX4 nor the names of its contributors may be
   *    used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
   * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
   * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   ****************************************************************************/
  
  #include "VehicleAcceleration.hpp"
  
  #include <px4_platform_common/log.h>
  
  using namespace matrix;
  using namespace time_literals;
  
  namespace sensors
  {
  
  VehicleAcceleration::VehicleAcceleration() :
  	ModuleParams(nullptr),
  	ScheduledWorkItem(MODULE_NAME, px4::wq_configurations::navigation_and_controllers),
  	_corrections(this, SensorCorrections::SensorType::Accelerometer)
  {
  	_lp_filter.set_cutoff_frequency(kInitialRateHz, _param_imu_accel_cutoff.get());
  }
  
  VehicleAcceleration::~VehicleAcceleration()
  {
  	Stop();
  }
  
  bool VehicleAcceleration::Start()
  {
  	// force initial updates
  	ParametersUpdate(true);
  
  	// sensor_selection needed to change the active sensor if the primary stops updating
  	if (!_sensor_selection_sub.registerCallback()) {
  		PX4_ERR("sensor_selection callback registration failed");
  		return false;
  	}
  
  	if (!SensorSelectionUpdate(true)) {
  		ScheduleDelayed(10_ms);
  	}
  
  	return true;
  }
  
  void VehicleAcceleration::Stop()
  {
  	// clear all registered callbacks
  	for (auto &sub : _sensor_sub) {
  		sub.unregisterCallback();
  	}
  
  	_sensor_selection_sub.unregisterCallback();
  
  	Deinit();
  }
  
  void VehicleAcceleration::CheckFilters()
  {
  	if (_interval_count > 1000) {
  		bool reset_filters = false;
  
  		// calculate sensor update rate
  		const float sample_interval_avg = _interval_sum / _interval_count;
  
  		if (PX4_ISFINITE(sample_interval_avg) && (sample_interval_avg > 0.0f)) {
  
  			_update_rate_hz = 1.e6f / sample_interval_avg;
  
  			// check if sample rate error is greater than 1%
  			if ((fabsf(_update_rate_hz - _filter_sample_rate) / _filter_sample_rate) > 0.01f) {
  				reset_filters = true;
  			}
  		}
  
  		if (!reset_filters) {
  			// accel low pass cutoff frequency changed
  			if (fabsf(_lp_filter.get_cutoff_freq() - _param_imu_accel_cutoff.get()) > 0.01f) {
  				reset_filters = true;
  			}
  		}
  
  		if (reset_filters) {
  			PX4_DEBUG("resetting filters, sample rate: %.3f Hz -> %.3f Hz", (double)_filter_sample_rate, (double)_update_rate_hz);
  			_filter_sample_rate = _update_rate_hz;
  
  			// update software low pass filters
  			_lp_filter.set_cutoff_frequency(_filter_sample_rate, _param_imu_accel_cutoff.get());
  			_lp_filter.reset(_acceleration_prev);
  		}
  
  		// reset sample interval accumulator
  		_timestamp_sample_last = 0;
  	}
  }
  
  void VehicleAcceleration::SensorBiasUpdate(bool force)
  {
  	if (_estimator_sensor_bias_sub.updated() || force) {
  		estimator_sensor_bias_s bias;
  
  		if (_estimator_sensor_bias_sub.copy(&bias)) {
  			if (bias.accel_device_id == _selected_sensor_device_id) {
  				_bias = Vector3f{bias.accel_bias};
  
  			} else {
  				_bias.zero();
  			}
  		}
  	}
  }
  
  bool VehicleAcceleration::SensorSelectionUpdate(bool force)
  {
  	if (_sensor_selection_sub.updated() || (_selected_sensor_device_id == 0) || force) {
  		sensor_selection_s sensor_selection{};
  		_sensor_selection_sub.copy(&sensor_selection);
  
  		if (_selected_sensor_device_id != sensor_selection.accel_device_id) {
  			// clear all registered callbacks
  			for (auto &sub : _sensor_sub) {
  				sub.unregisterCallback();
  			}
  
  			for (int i = 0; i < MAX_SENSOR_COUNT; i++) {
  				sensor_accel_s report{};
  				_sensor_sub[i].copy(&report);
  
  				if ((report.device_id != 0) && (report.device_id == sensor_selection.accel_device_id)) {
  					if (_sensor_sub[i].registerCallback()) {
  						PX4_DEBUG("selected sensor changed %d -> %d", _selected_sensor_sub_index, i);
  
  						// record selected sensor (array index)
  						_selected_sensor_sub_index = i;
  						_selected_sensor_device_id = sensor_selection.accel_device_id;
  
  						// clear bias and corrections
  						_bias.zero();
  
  						_corrections.set_device_id(report.device_id);
  
  						// reset sample interval accumulator on sensor change
  						_timestamp_sample_last = 0;
  
  						return true;
  					}
  				}
  			}
  
  			PX4_ERR("unable to find or subscribe to selected sensor (%d)", sensor_selection.accel_device_id);
  			_selected_sensor_device_id = 0;
  			_selected_sensor_sub_index = 0;
  		}
  	}
  
  	return false;
  }
  
  void VehicleAcceleration::ParametersUpdate(bool force)
  {
  	// Check if parameters have changed
  	if (_params_sub.updated() || force) {
  		// clear update
  		parameter_update_s param_update;
  		_params_sub.copy(&param_update);
  
  		updateParams();
  
  		_corrections.ParametersUpdate();
  	}
  }
  
  void VehicleAcceleration::Run()
  {
  	// backup schedule
  	ScheduleDelayed(10_ms);
  
  	// update corrections first to set _selected_sensor
  	bool selection_updated = SensorSelectionUpdate();
  
  	_corrections.SensorCorrectionsUpdate(selection_updated);
  	SensorBiasUpdate(selection_updated);
  	ParametersUpdate();
  
  	bool sensor_updated = _sensor_sub[_selected_sensor_sub_index].updated();
  
  	// process all outstanding messages
  	while (sensor_updated || selection_updated) {
  		selection_updated = false;
  
  		sensor_accel_s sensor_data;
  
  		if (_sensor_sub[_selected_sensor_sub_index].copy(&sensor_data)) {
  
  			if (sensor_updated) {
  				// collect sample interval average for filters
  				if ((_timestamp_sample_last > 0) && (sensor_data.timestamp_sample > _timestamp_sample_last)) {
  					_interval_sum += (sensor_data.timestamp_sample - _timestamp_sample_last);
  					_interval_count++;
  
  				} else {
  					_interval_sum = 0.f;
  					_interval_count = 0.f;
  				}
  
  				_timestamp_sample_last = sensor_data.timestamp_sample;
  			}
  
  			CheckFilters();
  
  			// Filter: apply low-pass
  			const Vector3f accel_filtered = _lp_filter.apply(Vector3f{sensor_data.x, sensor_data.y, sensor_data.z});
  
  			_acceleration_prev = accel_filtered;
  
  			// publish once all new samples are processed
  			sensor_updated = _sensor_sub[_selected_sensor_sub_index].updated();
  
  			if (!sensor_updated) {
  				// correct for in-run bias errors
  				const Vector3f accel = _corrections.Correct(accel_filtered) - _bias;
  
  				// Publish vehicle_acceleration
  				vehicle_acceleration_s v_acceleration;
  				v_acceleration.timestamp_sample = sensor_data.timestamp_sample;
  				accel.copyTo(v_acceleration.xyz);
  				v_acceleration.timestamp = hrt_absolute_time();
  				_vehicle_acceleration_pub.publish(v_acceleration);
  
  				_last_publish = v_acceleration.timestamp_sample;
  				return;
  			}
  		}
  	}
  }
  
  void VehicleAcceleration::PrintStatus()
  {
  	PX4_INFO("selected sensor: %d (%d), rate: %.1f Hz",
  		 _selected_sensor_device_id, _selected_sensor_sub_index, (double)_update_rate_hz);
  	PX4_INFO("estimated bias: [%.3f %.3f %.3f]", (double)_bias(0), (double)_bias(1), (double)_bias(2));
  	_corrections.PrintStatus();
  }
  
  } // namespace sensors
  