ardupilot/libraries/AP_InertialSensor/AP_InertialSensor_Backend.cpp

272 lines
8.8 KiB
C++

/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
#include <AP_HAL/AP_HAL.h>
#include "AP_InertialSensor.h"
#include "AP_InertialSensor_Backend.h"
#include <DataFlash/DataFlash.h>
const extern AP_HAL::HAL& hal;
AP_InertialSensor_Backend::AP_InertialSensor_Backend(AP_InertialSensor &imu) :
_imu(imu),
_product_id(AP_PRODUCT_ID_NONE)
{}
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.
*/
// 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)
{
// 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)
{
_imu._gyro[instance] = gyro;
_imu._gyro_healthy[instance] = true;
if (_imu._gyro_raw_sample_rates[instance] <= 0) {
return;
}
// publish delta angle
_imu._delta_angle[instance] = _imu._delta_angle_acc[instance];
_imu._delta_angle_dt[instance] = _imu._delta_angle_acc_dt[instance];
_imu._delta_angle_valid[instance] = true;
}
void AP_InertialSensor_Backend::_notify_new_gyro_raw_sample(uint8_t instance,
const Vector3f &gyro,
uint64_t sample_us)
{
float dt;
if (_imu._gyro_raw_sample_rates[instance] <= 0) {
return;
}
dt = 1.0f / _imu._gyro_raw_sample_rates[instance];
// 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;
// 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;
_imu._gyro_filtered[instance] = _imu._gyro_filter[instance].apply(gyro);
if (_imu._gyro_filtered[instance].is_nan() || _imu._gyro_filtered[instance].is_inf()) {
_imu._gyro_filter[instance].reset();
}
_imu._new_gyro_data[instance] = true;
DataFlash_Class *dataflash = get_dataflash();
if (dataflash != NULL) {
uint64_t now = AP_HAL::micros64();
struct log_GYRO pkt = {
LOG_PACKET_HEADER_INIT((uint8_t)(LOG_GYR1_MSG+instance)),
time_us : now,
sample_us : sample_us?sample_us:now,
GyrX : gyro.x,
GyrY : gyro.y,
GyrZ : gyro.z
};
dataflash->WriteBlock(&pkt, sizeof(pkt));
}
}
/*
rotate accel vector, scale and add the accel offset
*/
void AP_InertialSensor_Backend::_publish_accel(uint8_t instance, const Vector3f &accel)
{
_imu._accel[instance] = accel;
_imu._accel_healthy[instance] = true;
if (_imu._accel_raw_sample_rates[instance] <= 0) {
return;
}
// publish delta velocity
_imu._delta_velocity[instance] = _imu._delta_velocity_acc[instance];
_imu._delta_velocity_dt[instance] = _imu._delta_velocity_acc_dt[instance];
_imu._delta_velocity_valid[instance] = true;
if (_imu._accel_calibrator != NULL && _imu._accel_calibrator[instance].get_status() == ACCEL_CAL_COLLECTING_SAMPLE) {
Vector3f cal_sample = _imu._delta_velocity[instance];
//remove rotation
cal_sample.rotate_inverse(_imu._board_orientation);
// remove scale factors
const Vector3f &accel_scale = _imu._accel_scale[instance].get();
cal_sample.x /= accel_scale.x;
cal_sample.y /= accel_scale.y;
cal_sample.z /= accel_scale.z;
//remove offsets
cal_sample += _imu._accel_offset[instance].get() * _imu._delta_velocity_dt[instance] ;
_imu._accel_calibrator[instance].new_sample(cal_sample, _imu._delta_velocity_dt[instance]);
}
}
void AP_InertialSensor_Backend::_notify_new_accel_raw_sample(uint8_t instance,
const Vector3f &accel,
uint64_t sample_us)
{
float dt;
if (_imu._accel_raw_sample_rates[instance] <= 0) {
return;
}
dt = 1.0f / _imu._accel_raw_sample_rates[instance];
_imu.calc_vibration_and_clipping(instance, accel, dt);
// 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;
DataFlash_Class *dataflash = get_dataflash();
if (dataflash != NULL) {
uint64_t now = AP_HAL::micros64();
struct log_ACCEL pkt = {
LOG_PACKET_HEADER_INIT((uint8_t)(LOG_ACC1_MSG+instance)),
time_us : now,
sample_us : sample_us?sample_us:now,
AccX : accel.x,
AccY : accel.y,
AccZ : accel.z
};
dataflash->WriteBlock(&pkt, sizeof(pkt));
}
}
void AP_InertialSensor_Backend::_set_accel_max_abs_offset(uint8_t instance,
float max_offset)
{
_imu._accel_max_abs_offsets[instance] = max_offset;
}
// set accelerometer error_count
void AP_InertialSensor_Backend::_set_accel_error_count(uint8_t instance, uint32_t error_count)
{
_imu._accel_error_count[instance] = error_count;
}
// set gyro error_count
void AP_InertialSensor_Backend::_set_gyro_error_count(uint8_t instance, uint32_t error_count)
{
_imu._gyro_error_count[instance] = error_count;
}
// return the requested sample rate in Hz
uint16_t AP_InertialSensor_Backend::get_sample_rate_hz(void) const
{
// enum can be directly cast to Hz
return (uint16_t)_imu._sample_rate;
}
/*
publish a temperature value for an instance
*/
void AP_InertialSensor_Backend::_publish_temperature(uint8_t instance, float temperature)
{
_imu._temperature[instance] = temperature;
}
/*
common gyro update function for all backends
*/
void AP_InertialSensor_Backend::update_gyro(uint8_t instance)
{
hal.scheduler->suspend_timer_procs();
if (_imu._new_gyro_data[instance]) {
_publish_gyro(instance, _imu._gyro_filtered[instance]);
_imu._new_gyro_data[instance] = false;
}
// possibly update filter frequency
if (_last_gyro_filter_hz[instance] != _gyro_filter_cutoff()) {
_imu._gyro_filter[instance].set_cutoff_frequency(_gyro_raw_sample_rate(instance), _gyro_filter_cutoff());
_last_gyro_filter_hz[instance] = _gyro_filter_cutoff();
}
hal.scheduler->resume_timer_procs();
}
/*
common accel update function for all backends
*/
void AP_InertialSensor_Backend::update_accel(uint8_t instance)
{
hal.scheduler->suspend_timer_procs();
if (_imu._new_accel_data[instance]) {
_publish_accel(instance, _imu._accel_filtered[instance]);
_imu._new_accel_data[instance] = false;
}
// possibly update filter frequency
if (_last_accel_filter_hz[instance] != _accel_filter_cutoff()) {
_imu._accel_filter[instance].set_cutoff_frequency(_accel_raw_sample_rate(instance), _accel_filter_cutoff());
_last_accel_filter_hz[instance] = _accel_filter_cutoff();
}
hal.scheduler->resume_timer_procs();
}