/*
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see .
*/
/*
IMU temperature calibration handling
*/
#include "AP_InertialSensor.h"
#if HAL_INS_TEMPERATURE_CAL_ENABLE
#include
#include
#include
// this scale factor ensures params are easy to work with in GUI parameter editors
#define SCALE_FACTOR 1.0e6
#define INV_SCALE_FACTOR 1.0e-6
#define TEMP_RANGE_MIN 10
// timeout calibration after 10 minutes, if no temperature rise
#define CAL_TIMEOUT_MS (600U*1000U)
/*
we use a fixed reference temperature of 35C. This has the advantage
that we don't need to know the final temperature when doing an
online calibration which allows us to have a calibration timeout
*/
#define TEMP_REFERENCE 35.0
extern const AP_HAL::HAL& hal;
// temperature calibration parameters, per IMU
const AP_Param::GroupInfo AP_InertialSensor::TCal::var_info[] = {
// @Param: ENABLE
// @DisplayName: Enable temperature calibration
// @Description: Enable the use of temperature calibration parameters for this IMU. For automatic learning set to 2 and also set the INS_TCALn_TMAX to the target temperature, then reboot
// @Values: 0:Disabled,1:Enabled,2:LearnCalibration
// @User: Advanced
// @RebootRequired: True
AP_GROUPINFO_FLAGS("ENABLE", 1, AP_InertialSensor::TCal, enable, float(Enable::Disabled), AP_PARAM_FLAG_ENABLE),
// @Param: TMIN
// @DisplayName: Temperature calibration min
// @Description: The minimum temperature that the calibration is valid for
// @Range: -70 80
// @Units: degC
// @User: Advanced
// @Calibration: 1
AP_GROUPINFO("TMIN", 2, AP_InertialSensor::TCal, temp_min, 0),
// @Param: TMAX
// @DisplayName: Temperature calibration max
// @Description: The maximum temperature that the calibration is valid for. This must be at least 10 degrees above TMIN for calibration
// @Range: -70 80
// @Units: degC
// @User: Advanced
// @Calibration: 1
AP_GROUPINFO("TMAX", 3, AP_InertialSensor::TCal, temp_max, 0),
// @Param: ACC1_X
// @DisplayName: Accelerometer 1st order temperature coefficient X axis
// @Description: This is the 1st order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: ACC1_Y
// @DisplayName: Accelerometer 1st order temperature coefficient Y axis
// @Description: This is the 1st order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: ACC1_Z
// @DisplayName: Accelerometer 1st order temperature coefficient Z axis
// @Description: This is the 1st order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
AP_GROUPINFO("ACC1", 4, AP_InertialSensor::TCal, accel_coeff[0], 0),
// @Param: ACC2_X
// @DisplayName: Accelerometer 2nd order temperature coefficient X axis
// @Description: This is the 2nd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: ACC2_Y
// @DisplayName: Accelerometer 2nd order temperature coefficient Y axis
// @Description: This is the 2nd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: ACC2_Z
// @DisplayName: Accelerometer 2nd order temperature coefficient Z axis
// @Description: This is the 2nd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
AP_GROUPINFO("ACC2", 5, AP_InertialSensor::TCal, accel_coeff[1], 0),
// @Param: ACC3_X
// @DisplayName: Accelerometer 3rd order temperature coefficient X axis
// @Description: This is the 3rd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: ACC3_Y
// @DisplayName: Accelerometer 3rd order temperature coefficient Y axis
// @Description: This is the 3rd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: ACC3_Z
// @DisplayName: Accelerometer 3rd order temperature coefficient Z axis
// @Description: This is the 3rd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
AP_GROUPINFO("ACC3", 6, AP_InertialSensor::TCal, accel_coeff[2], 0),
// @Param: GYR1_X
// @DisplayName: Gyroscope 1st order temperature coefficient X axis
// @Description: This is the 1st order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: GYR1_Y
// @DisplayName: Gyroscope 1st order temperature coefficient Y axis
// @Description: This is the 1st order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: GYR1_Z
// @DisplayName: Gyroscope 1st order temperature coefficient Z axis
// @Description: This is the 1st order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
AP_GROUPINFO("GYR1", 7, AP_InertialSensor::TCal, gyro_coeff[0], 0),
// @Param: GYR2_X
// @DisplayName: Gyroscope 2nd order temperature coefficient X axis
// @Description: This is the 2nd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: GYR2_Y
// @DisplayName: Gyroscope 2nd order temperature coefficient Y axis
// @Description: This is the 2nd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: GYR2_Z
// @DisplayName: Gyroscope 2nd order temperature coefficient Z axis
// @Description: This is the 2nd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
AP_GROUPINFO("GYR2", 8, AP_InertialSensor::TCal, gyro_coeff[1], 0),
// @Param: GYR3_X
// @DisplayName: Gyroscope 3rd order temperature coefficient X axis
// @Description: This is the 3rd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: GYR3_Y
// @DisplayName: Gyroscope 3rd order temperature coefficient Y axis
// @Description: This is the 3rd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
// @Param: GYR3_Z
// @DisplayName: Gyroscope 3rd order temperature coefficient Z axis
// @Description: This is the 3rd order temperature coefficient from a temperature calibration
// @User: Advanced
// @Calibration: 1
AP_GROUPINFO("GYR3", 9, AP_InertialSensor::TCal, gyro_coeff[2], 0),
AP_GROUPEND
};
/*
evaluate a 3rd order polynomial (without the constant term) given a set of coefficients
*/
Vector3f AP_InertialSensor::TCal::polynomial_eval(float tdiff, const AP_Vector3f coeff[3]) const
{
// evaluate order 3 polynomial
const Vector3f *c = (Vector3f *)&coeff[0];
return (c[0] + (c[1] + c[2]*tdiff)*tdiff)*tdiff*INV_SCALE_FACTOR;
}
/*
correct a single sensor for the current temperature
*/
void AP_InertialSensor::TCal::correct_sensor(float temperature, float cal_temp, const AP_Vector3f coeff[3], Vector3f &v) const
{
if (enable != Enable::Enabled) {
return;
}
temperature = constrain_float(temperature, temp_min, temp_max);
cal_temp = constrain_float(cal_temp, temp_min, temp_max);
// get the polynomial correction for the difference between the
// current temperature and the mid temperature
v -= polynomial_eval(temperature - TEMP_REFERENCE, coeff);
// we need to add the correction for the temperature
// difference between the TREF, which is the reference used for
// the calibration process, and the cal_temp, which is the
// temperature that the offsets and scale factors was setup for
v += polynomial_eval(cal_temp - TEMP_REFERENCE, coeff);
}
void AP_InertialSensor::TCal::correct_accel(float temperature, float cal_temp, Vector3f &accel) const
{
correct_sensor(temperature, cal_temp, accel_coeff, accel);
}
void AP_InertialSensor::TCal::correct_gyro(float temperature, float cal_temp, Vector3f &gyro) const
{
correct_sensor(temperature, cal_temp, gyro_coeff, gyro);
}
/*
for SITL we don't apply the temperature limits and use mid-point as
reference. This makes the SITL data independent of TEMP_REFERENCE
and prevents an abrupt change at the endpoints
*/
void AP_InertialSensor::TCal::sitl_apply_accel(float temperature, Vector3f &accel) const
{
const float tmid = 0.5*(temp_max+temp_min);
accel += polynomial_eval(temperature - tmid, accel_coeff);
}
void AP_InertialSensor::TCal::sitl_apply_gyro(float temperature, Vector3f &gyro) const
{
const float tmid = 0.5*(temp_max+temp_min);
gyro += polynomial_eval(temperature - tmid, gyro_coeff);
}
AP_InertialSensor::TCal::Learn::Learn(TCal &_tcal, float _start_temp) :
start_temp(_start_temp),
tcal(_tcal)
{
reset(_start_temp);
}
/*
update polyfit with new sample
*/
void AP_InertialSensor::TCal::Learn::add_sample(const Vector3f &sample, float temperature, struct LearnState &st)
{
temperature = st.temp_filter.apply(temperature);
st.sum += sample;
st.sum_count++;
uint32_t now = AP_HAL::millis();
if (st.sum_count < 100 ||
temperature - st.last_temp < 0.5) {
// check for timeout
if (st.last_sample_ms != 0 &&
temperature - start_temp >= TEMP_RANGE_MIN &&
now - st.last_sample_ms > CAL_TIMEOUT_MS) {
// we have timed out, finish up now
finish_calibration(st.last_temp);
}
// wait for more data
return;
}
st.sum /= st.sum_count;
const uint8_t si = &st - &state[0];
const float T = (temperature + st.last_temp) * 0.5;
if (si == 0) {
// we use the first accel sample as the zero baseline
if (accel_start.is_zero()) {
accel_start = st.sum;
start_temp = T;
}
st.sum -= accel_start;
}
const float tdiff = T - TEMP_REFERENCE;
AP::logger().Write("TCLR", "TimeUS,I,SType,Temp,X,Y,Z,NSamp",
"s#------",
"F000000-",
"QBBffffI",
AP_HAL::micros64(),
instance(),
si,
T,
st.sum.x, st.sum.y, st.sum.z,
st.sum_count);
st.pfit.update(tdiff, st.sum);
st.sum.zero();
st.sum_count = 0;
st.last_temp = temperature;
st.last_sample_ms = now;
if (temperature - start_temp >= TEMP_RANGE_MIN) {
if (temperature >= start_tmax) {
// we've reached the target temperature
finish_calibration(temperature);
} else if (now - last_save_ms > 15000) {
// save partial calibration, so if user stops the cal part
// way then they still have a useful calibration
last_save_ms = now;
save_calibration(st.last_temp);
}
}
}
/*
update accel temperature compensation learning
*/
void AP_InertialSensor::TCal::update_accel_learning(const Vector3f &accel, float temperature)
{
if (enable != Enable::LearnCalibration) {
return;
}
if (learn == nullptr && hal.scheduler->is_system_initialized()) {
learn = new Learn(*this, temperature);
if (learn) {
GCS_SEND_TEXT(MAV_SEVERITY_WARNING, "TCAL[%u]: started calibration t=%.1fC tmax=%.1fC",
instance()+1,
temperature, learn->start_tmax);
AP_Notify::events.initiated_temp_cal = 1;
}
}
if (learn != nullptr) {
AP_Notify::flags.temp_cal_running = true;
learn->add_sample(accel, temperature, learn->state[0]);
}
}
/*
update gyro temperature compensation learning
*/
void AP_InertialSensor::TCal::update_gyro_learning(const Vector3f &gyro, float temperature)
{
if (enable != Enable::LearnCalibration) {
return;
}
if (learn != nullptr) {
learn->add_sample(gyro, temperature, learn->state[1]);
}
}
/*
reset calibration
*/
void AP_InertialSensor::TCal::Learn::reset(float temperature)
{
memset(state, 0, sizeof(state));
start_tmax = tcal.temp_max;
accel_start.zero();
for (uint8_t i=0; i 0) {
id[0] = '1'+i;
}
str.printf("INS_ACC%sOFFS_X=%f\n", id, aoff.x);
str.printf("INS_ACC%sOFFS_Y=%f\n", id, aoff.y);
str.printf("INS_ACC%sOFFS_Z=%f\n", id, aoff.z);
str.printf("INS_ACC%sSCAL_X=%f\n", id, ascl.x);
str.printf("INS_ACC%sSCAL_Y=%f\n", id, ascl.y);
str.printf("INS_ACC%sSCAL_Z=%f\n", id, ascl.z);
str.printf("INS_ACC%u_CALTEMP=%.2f\n", imu, caltemp_accel[i].get());
}
}
if (uint32_t(tcal_options.get()) & uint32_t(TCalOptions::PERSIST_TEMP_CAL)) {
for (auto &tc : tcal) {
tc.get_persistent_params(str);
}
save_options = true;
}
if (save_options) {
/*
we also have to save the TCAL_OPTIONS parameter so that
future flashing of the bootloader doesn't cause an erase
*/
str.printf("INS_TCAL_OPTIONS=%u\n", unsigned(tcal_options.get()));
}
}
#endif // HAL_INS_TEMPERATURE_CAL_ENABLE