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LibrePilot/flight/modules/Sensors/sensors.c
Corvus Corax 98c90a67f5 Undo James removal of gyro_bias and gyro_scale in revocalibration
Note that the EKF can only compensate for slow temperature drift, the gyros should be bias-zeroed before flight through calibration!
2013-04-27 23:59:52 +02:00

580 lines
17 KiB
C

/**
******************************************************************************
* @addtogroup OpenPilotModules OpenPilot Modules
* @{
* @addtogroup Sensors
* @brief Acquires sensor data
* Specifically updates the the @ref Gyros, @ref Accels, and @ref Magnetometer objects
* @{
*
* @file sensors.c
* @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
* @brief Module to handle all comms to the AHRS on a periodic basis.
*
* @see The GNU Public License (GPL) Version 3
*
******************************************************************************/
/*
* 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, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/**
* Input objects: None, takes sensor data via pios
* Output objects: @ref Gyros @ref Accels @ref Magnetometer
*
* The module executes in its own thread.
*
* UAVObjects are automatically generated by the UAVObjectGenerator from
* the object definition XML file.
*
* Modules have no API, all communication to other modules is done through UAVObjects.
* However modules may use the API exposed by shared libraries.
* See the OpenPilot wiki for more details.
* http://www.openpilot.org/OpenPilot_Application_Architecture
*
*/
#include <openpilot.h>
#include <homelocation.h>
#include <magnetometer.h>
#include <magbias.h>
#include <accels.h>
#include <gyros.h>
#include <gyrosbias.h>
#include <attitudeactual.h>
#include <attitudesettings.h>
#include <revocalibration.h>
#include <flightstatus.h>
#include <CoordinateConversions.h>
#include <pios_math.h>
#include <pios_board_info.h>
// Private constants
#define STACK_SIZE_BYTES 1000
#define TASK_PRIORITY (tskIDLE_PRIORITY+3)
#define SENSOR_PERIOD 2
// Private types
// Private functions
static void SensorsTask(void *parameters);
static void settingsUpdatedCb(UAVObjEvent * objEv);
static void magOffsetEstimation(MagnetometerData *mag);
// Private variables
static xTaskHandle sensorsTaskHandle;
RevoCalibrationData cal;
// These values are initialized by settings but can be updated by the attitude algorithm
static bool bias_correct_gyro = true;
static float mag_bias[3] = {0,0,0};
static float mag_scale[3] = {0,0,0};
static float accel_bias[3] = {0,0,0};
static float accel_scale[3] = {0,0,0};
static float gyro_staticbias[3] = {0,0,0};
static float gyro_scale[3] = {0,0,0};
static float R[3][3] = {{0}};
static int8_t rotate = 0;
/**
* API for sensor fusion algorithms:
* Configure(xQueueHandle gyro, xQueueHandle accel, xQueueHandle mag, xQueueHandle baro)
* Stores all the queues the algorithm will pull data from
* FinalizeSensors() -- before saving the sensors modifies them based on internal state (gyro bias)
* Update() -- queries queues and updates the attitude estiamte
*/
/**
* Initialise the module. Called before the start function
* \returns 0 on success or -1 if initialisation failed
*/
int32_t SensorsInitialize(void)
{
GyrosInitialize();
GyrosBiasInitialize();
AccelsInitialize();
MagnetometerInitialize();
MagBiasInitialize();
RevoCalibrationInitialize();
AttitudeSettingsInitialize();
rotate = 0;
RevoCalibrationConnectCallback(&settingsUpdatedCb);
AttitudeSettingsConnectCallback(&settingsUpdatedCb);
return 0;
}
/**
* Start the task. Expects all objects to be initialized by this point.
* \returns 0 on success or -1 if initialisation failed
*/
int32_t SensorsStart(void)
{
// Start main task
xTaskCreate(SensorsTask, (signed char *)"Sensors", STACK_SIZE_BYTES/4, NULL, TASK_PRIORITY, &sensorsTaskHandle);
TaskMonitorAdd(TASKINFO_RUNNING_SENSORS, sensorsTaskHandle);
PIOS_WDG_RegisterFlag(PIOS_WDG_SENSORS);
return 0;
}
MODULE_INITCALL(SensorsInitialize, SensorsStart)
int32_t accel_test;
int32_t gyro_test;
int32_t mag_test;
//int32_t pressure_test;
/**
* The sensor task. This polls the gyros at 500 Hz and pumps that data to
* stabilization and to the attitude loop
*
* This function has a lot of if/defs right now to allow these configurations:
* 1. BMA180 accel and MPU6000 gyro
* 2. MPU6000 gyro and accel
* 3. BMA180 accel and L3GD20 gyro
*/
uint32_t sensor_dt_us;
static void SensorsTask(void *parameters)
{
portTickType lastSysTime;
uint32_t accel_samples = 0;
uint32_t gyro_samples = 0;
int32_t accel_accum[3] = {0, 0, 0};
int32_t gyro_accum[3] = {0,0,0};
float gyro_scaling = 0;
float accel_scaling = 0;
static int32_t timeval;
AlarmsClear(SYSTEMALARMS_ALARM_SENSORS);
UAVObjEvent ev;
settingsUpdatedCb(&ev);
const struct pios_board_info * bdinfo = &pios_board_info_blob;
switch(bdinfo->board_rev) {
case 0x01:
#if defined(PIOS_INCLUDE_L3GD20)
gyro_test = PIOS_L3GD20_Test();
#endif
#if defined(PIOS_INCLUDE_BMA180)
accel_test = PIOS_BMA180_Test();
#endif
break;
case 0x02:
#if defined(PIOS_INCLUDE_MPU6000)
gyro_test = PIOS_MPU6000_Test();
accel_test = gyro_test;
#endif
break;
default:
PIOS_DEBUG_Assert(0);
}
#if defined(PIOS_INCLUDE_HMC5883)
mag_test = PIOS_HMC5883_Test();
#else
mag_test = 0;
#endif
if(accel_test < 0 || gyro_test < 0 || mag_test < 0) {
AlarmsSet(SYSTEMALARMS_ALARM_SENSORS, SYSTEMALARMS_ALARM_CRITICAL);
while(1) {
PIOS_WDG_UpdateFlag(PIOS_WDG_SENSORS);
vTaskDelay(10);
}
}
// Main task loop
lastSysTime = xTaskGetTickCount();
bool error = false;
uint32_t mag_update_time = PIOS_DELAY_GetRaw();
while (1) {
// TODO: add timeouts to the sensor reads and set an error if the fail
sensor_dt_us = PIOS_DELAY_DiffuS(timeval);
timeval = PIOS_DELAY_GetRaw();
if (error) {
PIOS_WDG_UpdateFlag(PIOS_WDG_SENSORS);
lastSysTime = xTaskGetTickCount();
vTaskDelayUntil(&lastSysTime, SENSOR_PERIOD / portTICK_RATE_MS);
AlarmsSet(SYSTEMALARMS_ALARM_SENSORS, SYSTEMALARMS_ALARM_CRITICAL);
error = false;
} else {
AlarmsClear(SYSTEMALARMS_ALARM_SENSORS);
}
for (int i = 0; i < 3; i++) {
accel_accum[i] = 0;
gyro_accum[i] = 0;
}
accel_samples = 0;
gyro_samples = 0;
AccelsData accelsData;
GyrosData gyrosData;
switch(bdinfo->board_rev) {
case 0x01: // L3GD20 + BMA180 board
#if defined(PIOS_INCLUDE_BMA180)
{
struct pios_bma180_data accel;
int32_t read_good;
int32_t count;
count = 0;
while((read_good = PIOS_BMA180_ReadFifo(&accel)) != 0 && !error)
error = ((xTaskGetTickCount() - lastSysTime) > SENSOR_PERIOD) ? true : error;
if (error) {
// Unfortunately if the BMA180 ever misses getting read, then it will not
// trigger more interrupts. In this case we must force a read to kickstarts
// it.
struct pios_bma180_data data;
PIOS_BMA180_ReadAccels(&data);
continue;
}
while(read_good == 0) {
count++;
accel_accum[1] += accel.x;
accel_accum[0] += accel.y;
accel_accum[2] -= accel.z;
read_good = PIOS_BMA180_ReadFifo(&accel);
}
accel_samples = count;
accel_scaling = PIOS_BMA180_GetScale();
// Get temp from last reading
accelsData.temperature = 25.0f + ((float) accel.temperature - 2.0f) / 2.0f;
}
#endif
#if defined(PIOS_INCLUDE_L3GD20)
{
struct pios_l3gd20_data gyro;
gyro_samples = 0;
xQueueHandle gyro_queue = PIOS_L3GD20_GetQueue();
if(xQueueReceive(gyro_queue, (void *) &gyro, 4) == errQUEUE_EMPTY) {
error = true;
continue;
}
gyro_samples = 1;
gyro_accum[1] += gyro.gyro_x;
gyro_accum[0] += gyro.gyro_y;
gyro_accum[2] -= gyro.gyro_z;
gyro_scaling = PIOS_L3GD20_GetScale();
// Get temp from last reading
gyrosData.temperature = gyro.temperature;
}
#endif
break;
case 0x02: // MPU6000 board
case 0x03: // MPU6000 board
#if defined(PIOS_INCLUDE_MPU6000)
{
struct pios_mpu6000_data mpu6000_data;
xQueueHandle queue = PIOS_MPU6000_GetQueue();
while(xQueueReceive(queue, (void *) &mpu6000_data, gyro_samples == 0 ? 10 : 0) != errQUEUE_EMPTY)
{
gyro_accum[0] += mpu6000_data.gyro_x;
gyro_accum[1] += mpu6000_data.gyro_y;
gyro_accum[2] += mpu6000_data.gyro_z;
accel_accum[0] += mpu6000_data.accel_x;
accel_accum[1] += mpu6000_data.accel_y;
accel_accum[2] += mpu6000_data.accel_z;
gyro_samples ++;
accel_samples ++;
}
if (gyro_samples == 0) {
PIOS_MPU6000_ReadGyros(&mpu6000_data);
error = true;
continue;
}
gyro_scaling = PIOS_MPU6000_GetScale();
accel_scaling = PIOS_MPU6000_GetAccelScale();
gyrosData.temperature = 35.0f + ((float) mpu6000_data.temperature + 512.0f) / 340.0f;
accelsData.temperature = 35.0f + ((float) mpu6000_data.temperature + 512.0f) / 340.0f;
}
#endif /* PIOS_INCLUDE_MPU6000 */
break;
default:
PIOS_DEBUG_Assert(0);
}
// Scale the accels
float accels[3] = {(float) accel_accum[0] / accel_samples,
(float) accel_accum[1] / accel_samples,
(float) accel_accum[2] / accel_samples};
float accels_out[3] = {accels[0] * accel_scaling * accel_scale[0] - accel_bias[0],
accels[1] * accel_scaling * accel_scale[1] - accel_bias[1],
accels[2] * accel_scaling * accel_scale[2] - accel_bias[2]};
if (rotate) {
rot_mult(R, accels_out, accels);
accelsData.x = accels[0];
accelsData.y = accels[1];
accelsData.z = accels[2];
} else {
accelsData.x = accels_out[0];
accelsData.y = accels_out[1];
accelsData.z = accels_out[2];
}
AccelsSet(&accelsData);
// Scale the gyros
float gyros[3] = {(float) gyro_accum[0] / gyro_samples,
(float) gyro_accum[1] / gyro_samples,
(float) gyro_accum[2] / gyro_samples};
float gyros_out[3] = {gyros[0] * gyro_scaling * gyro_scale[0] - gyro_staticbias[0],
gyros[1] * gyro_scaling * gyro_scale[1] - gyro_staticbias[1],
gyros[2] * gyro_scaling * gyro_scale[2] - gyro_staticbias[2]};
if (rotate) {
rot_mult(R, gyros_out, gyros);
gyrosData.x = gyros[0];
gyrosData.y = gyros[1];
gyrosData.z = gyros[2];
} else {
gyrosData.x = gyros_out[0];
gyrosData.y = gyros_out[1];
gyrosData.z = gyros_out[2];
}
if (bias_correct_gyro) {
// Apply bias correction to the gyros from the state estimator
GyrosBiasData gyrosBias;
GyrosBiasGet(&gyrosBias);
gyrosData.x -= gyrosBias.x;
gyrosData.y -= gyrosBias.y;
gyrosData.z -= gyrosBias.z;
}
GyrosSet(&gyrosData);
// Because most crafts wont get enough information from gravity to zero yaw gyro, we try
// and make it average zero (weakly)
#if defined(PIOS_INCLUDE_HMC5883)
MagnetometerData mag;
if (PIOS_HMC5883_NewDataAvailable() || PIOS_DELAY_DiffuS(mag_update_time) > 150000) {
int16_t values[3];
PIOS_HMC5883_ReadMag(values);
float mags[3] = {(float) values[1] * mag_scale[0] - mag_bias[0],
(float) values[0] * mag_scale[1] - mag_bias[1],
-(float) values[2] * mag_scale[2] - mag_bias[2]};
if (rotate) {
float mag_out[3];
rot_mult(R, mags, mag_out);
mag.x = mag_out[0];
mag.y = mag_out[1];
mag.z = mag_out[2];
} else {
mag.x = mags[0];
mag.y = mags[1];
mag.z = mags[2];
}
// Correct for mag bias and update if the rate is non zero
if(cal.MagBiasNullingRate > 0)
magOffsetEstimation(&mag);
MagnetometerSet(&mag);
mag_update_time = PIOS_DELAY_GetRaw();
}
#endif
PIOS_WDG_UpdateFlag(PIOS_WDG_SENSORS);
lastSysTime = xTaskGetTickCount();
}
}
/**
* Perform an update of the @ref MagBias based on
* Magnetometer Offset Cancellation: Theory and Implementation,
* revisited William Premerlani, October 14, 2011
*/
static void magOffsetEstimation(MagnetometerData *mag)
{
#if 0
// Constants, to possibly go into a UAVO
static const float MIN_NORM_DIFFERENCE = 50;
static float B2[3] = {0, 0, 0};
MagBiasData magBias;
MagBiasGet(&magBias);
// Remove the current estimate of the bias
mag->x -= magBias.x;
mag->y -= magBias.y;
mag->z -= magBias.z;
// First call
if (B2[0] == 0 && B2[1] == 0 && B2[2] == 0) {
B2[0] = mag->x;
B2[1] = mag->y;
B2[2] = mag->z;
return;
}
float B1[3] = {mag->x, mag->y, mag->z};
float norm_diff = sqrtf(powf(B2[0] - B1[0],2) + powf(B2[1] - B1[1],2) + powf(B2[2] - B1[2],2));
if (norm_diff > MIN_NORM_DIFFERENCE) {
float norm_b1 = sqrtf(B1[0]*B1[0] + B1[1]*B1[1] + B1[2]*B1[2]);
float norm_b2 = sqrtf(B2[0]*B2[0] + B2[1]*B2[1] + B2[2]*B2[2]);
float scale = cal.MagBiasNullingRate * (norm_b2 - norm_b1) / norm_diff;
float b_error[3] = {(B2[0] - B1[0]) * scale, (B2[1] - B1[1]) * scale, (B2[2] - B1[2]) * scale};
magBias.x += b_error[0];
magBias.y += b_error[1];
magBias.z += b_error[2];
MagBiasSet(&magBias);
// Store this value to compare against next update
B2[0] = B1[0]; B2[1] = B1[1]; B2[2] = B1[2];
}
#else
MagBiasData magBias;
MagBiasGet(&magBias);
// Remove the current estimate of the bias
mag->x -= magBias.x;
mag->y -= magBias.y;
mag->z -= magBias.z;
HomeLocationData homeLocation;
HomeLocationGet(&homeLocation);
AttitudeActualData attitude;
AttitudeActualGet(&attitude);
const float Rxy = sqrtf(homeLocation.Be[0]*homeLocation.Be[0] + homeLocation.Be[1]*homeLocation.Be[1]);
const float Rz = homeLocation.Be[2];
const float rate = cal.MagBiasNullingRate;
float R[3][3];
float B_e[3];
float xy[2];
float delta[3];
// Get the rotation matrix
Quaternion2R(&attitude.q1, R);
// Rotate the mag into the NED frame
B_e[0] = R[0][0] * mag->x + R[1][0] * mag->y + R[2][0] * mag->z;
B_e[1] = R[0][1] * mag->x + R[1][1] * mag->y + R[2][1] * mag->z;
B_e[2] = R[0][2] * mag->x + R[1][2] * mag->y + R[2][2] * mag->z;
float cy = cosf(DEG2RAD(attitude.Yaw));
float sy = sinf(DEG2RAD(attitude.Yaw));
xy[0] = cy * B_e[0] + sy * B_e[1];
xy[1] = -sy * B_e[0] + cy * B_e[1];
float xy_norm = sqrtf(xy[0]*xy[0] + xy[1]*xy[1]);
delta[0] = -rate * (xy[0] / xy_norm * Rxy - xy[0]);
delta[1] = -rate * (xy[1] / xy_norm * Rxy - xy[1]);
delta[2] = -rate * (Rz - B_e[2]);
if (delta[0] == delta[0] && delta[1] == delta[1] && delta[2] == delta[2]) {
magBias.x += delta[0];
magBias.y += delta[1];
magBias.z += delta[2];
MagBiasSet(&magBias);
}
#endif
}
/**
* Locally cache some variables from the AtttitudeSettings object
*/
static void settingsUpdatedCb(UAVObjEvent * objEv) {
RevoCalibrationGet(&cal);
mag_bias[0] = cal.mag_bias[REVOCALIBRATION_MAG_BIAS_X];
mag_bias[1] = cal.mag_bias[REVOCALIBRATION_MAG_BIAS_Y];
mag_bias[2] = cal.mag_bias[REVOCALIBRATION_MAG_BIAS_Z];
mag_scale[0] = cal.mag_scale[REVOCALIBRATION_MAG_SCALE_X];
mag_scale[1] = cal.mag_scale[REVOCALIBRATION_MAG_SCALE_Y];
mag_scale[2] = cal.mag_scale[REVOCALIBRATION_MAG_SCALE_Z];
accel_bias[0] = cal.accel_bias[REVOCALIBRATION_ACCEL_BIAS_X];
accel_bias[1] = cal.accel_bias[REVOCALIBRATION_ACCEL_BIAS_Y];
accel_bias[2] = cal.accel_bias[REVOCALIBRATION_ACCEL_BIAS_Z];
accel_scale[0] = cal.accel_scale[REVOCALIBRATION_ACCEL_SCALE_X];
accel_scale[1] = cal.accel_scale[REVOCALIBRATION_ACCEL_SCALE_Y];
accel_scale[2] = cal.accel_scale[REVOCALIBRATION_ACCEL_SCALE_Z];
gyro_staticbias[0] = cal.gyro_bias[REVOCALIBRATION_GYRO_BIAS_X];
gyro_staticbias[1] = cal.gyro_bias[REVOCALIBRATION_GYRO_BIAS_Y];
gyro_staticbias[2] = cal.gyro_bias[REVOCALIBRATION_GYRO_BIAS_Z];
gyro_scale[0] = cal.gyro_scale[REVOCALIBRATION_GYRO_SCALE_X];
gyro_scale[1] = cal.gyro_scale[REVOCALIBRATION_GYRO_SCALE_Y];
gyro_scale[2] = cal.gyro_scale[REVOCALIBRATION_GYRO_SCALE_Z];
// Zero out any adaptive tracking
MagBiasData magBias;
MagBiasGet(&magBias);
magBias.x = 0;
magBias.y = 0;
magBias.z = 0;
MagBiasSet(&magBias);
AttitudeSettingsData attitudeSettings;
AttitudeSettingsGet(&attitudeSettings);
bias_correct_gyro = (cal.BiasCorrectedRaw == REVOCALIBRATION_BIASCORRECTEDRAW_TRUE);
// Indicates not to expend cycles on rotation
if(attitudeSettings.BoardRotation[0] == 0 && attitudeSettings.BoardRotation[1] == 0 &&
attitudeSettings.BoardRotation[2] == 0) {
rotate = 0;
} else {
float rotationQuat[4];
const float rpy[3] = {attitudeSettings.BoardRotation[ATTITUDESETTINGS_BOARDROTATION_ROLL],
attitudeSettings.BoardRotation[ATTITUDESETTINGS_BOARDROTATION_PITCH],
attitudeSettings.BoardRotation[ATTITUDESETTINGS_BOARDROTATION_YAW]};
RPY2Quaternion(rpy, rotationQuat);
Quaternion2R(rotationQuat, R);
rotate = 1;
}
}
/**
* @}
* @}
*/