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Diffstat (limited to 'src/modules/commander/accelerometer_calibration.c')
-rw-r--r--src/modules/commander/accelerometer_calibration.c414
1 files changed, 0 insertions, 414 deletions
diff --git a/src/modules/commander/accelerometer_calibration.c b/src/modules/commander/accelerometer_calibration.c
deleted file mode 100644
index d79dd93dd..000000000
--- a/src/modules/commander/accelerometer_calibration.c
+++ /dev/null
@@ -1,414 +0,0 @@
-/*
- * accelerometer_calibration.c
- *
- * Copyright (C) 2013 Anton Babushkin. All rights reserved.
- * Author: Anton Babushkin <rk3dov@gmail.com>
- *
- * Transform acceleration vector to true orientation and scale
- *
- * * * * Model * * *
- * accel_corr = accel_T * (accel_raw - accel_offs)
- *
- * accel_corr[3] - fully corrected acceleration vector in body frame
- * accel_T[3][3] - accelerometers transform matrix, rotation and scaling transform
- * accel_raw[3] - raw acceleration vector
- * accel_offs[3] - acceleration offset vector
- *
- * * * * Calibration * * *
- *
- * Reference vectors
- * accel_corr_ref[6][3] = [ g 0 0 ] // nose up
- * | -g 0 0 | // nose down
- * | 0 g 0 | // left side down
- * | 0 -g 0 | // right side down
- * | 0 0 g | // on back
- * [ 0 0 -g ] // level
- * accel_raw_ref[6][3]
- *
- * accel_corr_ref[i] = accel_T * (accel_raw_ref[i] - accel_offs), i = 0...5
- *
- * 6 reference vectors * 3 axes = 18 equations
- * 9 (accel_T) + 3 (accel_offs) = 12 unknown constants
- *
- * Find accel_offs
- *
- * accel_offs[i] = (accel_raw_ref[i*2][i] + accel_raw_ref[i*2+1][i]) / 2
- *
- *
- * Find accel_T
- *
- * 9 unknown constants
- * need 9 equations -> use 3 of 6 measurements -> 3 * 3 = 9 equations
- *
- * accel_corr_ref[i*2] = accel_T * (accel_raw_ref[i*2] - accel_offs), i = 0...2
- *
- * Solve separate system for each row of accel_T:
- *
- * accel_corr_ref[j*2][i] = accel_T[i] * (accel_raw_ref[j*2] - accel_offs), j = 0...2
- *
- * A * x = b
- *
- * x = [ accel_T[0][i] ]
- * | accel_T[1][i] |
- * [ accel_T[2][i] ]
- *
- * b = [ accel_corr_ref[0][i] ] // One measurement per axis is enough
- * | accel_corr_ref[2][i] |
- * [ accel_corr_ref[4][i] ]
- *
- * a[i][j] = accel_raw_ref[i][j] - accel_offs[j], i = 0;2;4, j = 0...2
- *
- * Matrix A is common for all three systems:
- * A = [ a[0][0] a[0][1] a[0][2] ]
- * | a[2][0] a[2][1] a[2][2] |
- * [ a[4][0] a[4][1] a[4][2] ]
- *
- * x = A^-1 * b
- *
- * accel_T = A^-1 * g
- * g = 9.80665
- */
-
-#include "accelerometer_calibration.h"
-
-#include <poll.h>
-#include <drivers/drv_hrt.h>
-#include <uORB/topics/sensor_combined.h>
-#include <drivers/drv_accel.h>
-#include <systemlib/conversions.h>
-#include <mavlink/mavlink_log.h>
-
-void do_accel_calibration(int status_pub, struct vehicle_status_s *status, int mavlink_fd);
-int do_accel_calibration_mesurements(int mavlink_fd, float accel_offs[3], float accel_scale[3]);
-int detect_orientation(int mavlink_fd, int sub_sensor_combined);
-int read_accelerometer_avg(int sensor_combined_sub, float accel_avg[3], int samples_num);
-int mat_invert3(float src[3][3], float dst[3][3]);
-int calculate_calibration_values(float accel_ref[6][3], float accel_T[3][3], float accel_offs[3], float g);
-
-void do_accel_calibration(int status_pub, struct vehicle_status_s *status, int mavlink_fd) {
- /* announce change */
- mavlink_log_info(mavlink_fd, "accel calibration started");
- /* set to accel calibration mode */
- status->flag_preflight_accel_calibration = true;
- state_machine_publish(status_pub, status, mavlink_fd);
-
- /* measure and calculate offsets & scales */
- float accel_offs[3];
- float accel_scale[3];
- int res = do_accel_calibration_mesurements(mavlink_fd, accel_offs, accel_scale);
-
- if (res == OK) {
- /* measurements complete successfully, set parameters */
- if (param_set(param_find("SENS_ACC_XOFF"), &(accel_offs[0]))
- || param_set(param_find("SENS_ACC_YOFF"), &(accel_offs[1]))
- || param_set(param_find("SENS_ACC_ZOFF"), &(accel_offs[2]))
- || param_set(param_find("SENS_ACC_XSCALE"), &(accel_scale[0]))
- || param_set(param_find("SENS_ACC_YSCALE"), &(accel_scale[1]))
- || param_set(param_find("SENS_ACC_ZSCALE"), &(accel_scale[2]))) {
- mavlink_log_critical(mavlink_fd, "ERROR: setting offs or scale failed");
- }
-
- int fd = open(ACCEL_DEVICE_PATH, 0);
- struct accel_scale ascale = {
- accel_offs[0],
- accel_scale[0],
- accel_offs[1],
- accel_scale[1],
- accel_offs[2],
- accel_scale[2],
- };
-
- if (OK != ioctl(fd, ACCELIOCSSCALE, (long unsigned int)&ascale))
- warn("WARNING: failed to set scale / offsets for accel");
-
- close(fd);
-
- /* auto-save to EEPROM */
- int save_ret = param_save_default();
-
- if (save_ret != 0) {
- warn("WARNING: auto-save of params to storage failed");
- }
-
- mavlink_log_info(mavlink_fd, "accel calibration done");
- tune_confirm();
- sleep(2);
- tune_confirm();
- sleep(2);
- /* third beep by cal end routine */
- } else {
- /* measurements error */
- mavlink_log_info(mavlink_fd, "accel calibration aborted");
- tune_error();
- sleep(2);
- }
-
- /* exit accel calibration mode */
- status->flag_preflight_accel_calibration = false;
- state_machine_publish(status_pub, status, mavlink_fd);
-}
-
-int do_accel_calibration_mesurements(int mavlink_fd, float accel_offs[3], float accel_scale[3]) {
- const int samples_num = 2500;
- float accel_ref[6][3];
- bool data_collected[6] = { false, false, false, false, false, false };
- const char *orientation_strs[6] = { "x+", "x-", "y+", "y-", "z+", "z-" };
-
- /* reset existing calibration */
- int fd = open(ACCEL_DEVICE_PATH, 0);
- struct accel_scale ascale_null = {
- 0.0f,
- 1.0f,
- 0.0f,
- 1.0f,
- 0.0f,
- 1.0f,
- };
- int ioctl_res = ioctl(fd, ACCELIOCSSCALE, (long unsigned int)&ascale_null);
- close(fd);
-
- if (OK != ioctl_res) {
- warn("ERROR: failed to set scale / offsets for accel");
- return ERROR;
- }
-
- int sensor_combined_sub = orb_subscribe(ORB_ID(sensor_combined));
- while (true) {
- bool done = true;
- char str[80];
- int str_ptr;
- str_ptr = sprintf(str, "keep vehicle still:");
- for (int i = 0; i < 6; i++) {
- if (!data_collected[i]) {
- str_ptr += sprintf(&(str[str_ptr]), " %s", orientation_strs[i]);
- done = false;
- }
- }
- if (done)
- break;
- mavlink_log_info(mavlink_fd, str);
-
- int orient = detect_orientation(mavlink_fd, sensor_combined_sub);
- if (orient < 0)
- return ERROR;
-
- sprintf(str, "meas started: %s", orientation_strs[orient]);
- mavlink_log_info(mavlink_fd, str);
- read_accelerometer_avg(sensor_combined_sub, &(accel_ref[orient][0]), samples_num);
- str_ptr = sprintf(str, "meas result for %s: [ %.2f %.2f %.2f ]", orientation_strs[orient], accel_ref[orient][0], accel_ref[orient][1], accel_ref[orient][2]);
- mavlink_log_info(mavlink_fd, str);
- data_collected[orient] = true;
- tune_confirm();
- }
- close(sensor_combined_sub);
-
- /* calculate offsets and rotation+scale matrix */
- float accel_T[3][3];
- int res = calculate_calibration_values(accel_ref, accel_T, accel_offs, CONSTANTS_ONE_G);
- if (res != 0) {
- mavlink_log_info(mavlink_fd, "ERROR: calibration values calc error");
- return ERROR;
- }
-
- /* convert accel transform matrix to scales,
- * rotation part of transform matrix is not used by now
- */
- for (int i = 0; i < 3; i++) {
- accel_scale[i] = accel_T[i][i];
- }
-
- return OK;
-}
-
-/*
- * Wait for vehicle become still and detect it's orientation.
- *
- * @return 0..5 according to orientation when vehicle is still and ready for measurements,
- * ERROR if vehicle is not still after 30s or orientation error is more than 5m/s^2
- */
-int detect_orientation(int mavlink_fd, int sub_sensor_combined) {
- struct sensor_combined_s sensor;
- /* exponential moving average of accel */
- float accel_ema[3] = { 0.0f, 0.0f, 0.0f };
- /* max-hold dispersion of accel */
- float accel_disp[3] = { 0.0f, 0.0f, 0.0f };
- /* EMA time constant in seconds*/
- float ema_len = 0.2f;
- /* set "still" threshold to 0.1 m/s^2 */
- float still_thr2 = pow(0.1f, 2);
- /* set accel error threshold to 5m/s^2 */
- float accel_err_thr = 5.0f;
- /* still time required in us */
- int64_t still_time = 2000000;
- struct pollfd fds[1] = { { .fd = sub_sensor_combined, .events = POLLIN } };
-
- hrt_abstime t_start = hrt_absolute_time();
- /* set timeout to 30s */
- hrt_abstime timeout = 30000000;
- hrt_abstime t_timeout = t_start + timeout;
- hrt_abstime t = t_start;
- hrt_abstime t_prev = t_start;
- hrt_abstime t_still = 0;
- while (true) {
- /* wait blocking for new data */
- int poll_ret = poll(fds, 1, 1000);
- if (poll_ret) {
- orb_copy(ORB_ID(sensor_combined), sub_sensor_combined, &sensor);
- t = hrt_absolute_time();
- float dt = (t - t_prev) / 1000000.0f;
- t_prev = t;
- float w = dt / ema_len;
- for (int i = 0; i < 3; i++) {
- accel_ema[i] = accel_ema[i] * (1.0f - w) + sensor.accelerometer_m_s2[i] * w;
- float d = (float) sensor.accelerometer_m_s2[i] - accel_ema[i];
- d = d * d;
- accel_disp[i] = accel_disp[i] * (1.0f - w);
- if (d > accel_disp[i])
- accel_disp[i] = d;
- }
- /* still detector with hysteresis */
- if ( accel_disp[0] < still_thr2 &&
- accel_disp[1] < still_thr2 &&
- accel_disp[2] < still_thr2 ) {
- /* is still now */
- if (t_still == 0) {
- /* first time */
- mavlink_log_info(mavlink_fd, "still...");
- t_still = t;
- t_timeout = t + timeout;
- } else {
- /* still since t_still */
- if ((int64_t) t - (int64_t) t_still > still_time) {
- /* vehicle is still, exit from the loop to detection of its orientation */
- break;
- }
- }
- } else if ( accel_disp[0] > still_thr2 * 2.0f ||
- accel_disp[1] > still_thr2 * 2.0f ||
- accel_disp[2] > still_thr2 * 2.0f) {
- /* not still, reset still start time */
- if (t_still != 0) {
- mavlink_log_info(mavlink_fd, "moving...");
- t_still = 0;
- }
- }
- } else if (poll_ret == 0) {
- /* any poll failure for 1s is a reason to abort */
- mavlink_log_info(mavlink_fd, "ERROR: poll failure");
- return -3;
- }
- if (t > t_timeout) {
- mavlink_log_info(mavlink_fd, "ERROR: timeout");
- return -1;
- }
- }
-
- if ( fabs(accel_ema[0] - CONSTANTS_ONE_G) < accel_err_thr &&
- fabs(accel_ema[1]) < accel_err_thr &&
- fabs(accel_ema[2]) < accel_err_thr )
- return 0; // [ g, 0, 0 ]
- if ( fabs(accel_ema[0] + CONSTANTS_ONE_G) < accel_err_thr &&
- fabs(accel_ema[1]) < accel_err_thr &&
- fabs(accel_ema[2]) < accel_err_thr )
- return 1; // [ -g, 0, 0 ]
- if ( fabs(accel_ema[0]) < accel_err_thr &&
- fabs(accel_ema[1] - CONSTANTS_ONE_G) < accel_err_thr &&
- fabs(accel_ema[2]) < accel_err_thr )
- return 2; // [ 0, g, 0 ]
- if ( fabs(accel_ema[0]) < accel_err_thr &&
- fabs(accel_ema[1] + CONSTANTS_ONE_G) < accel_err_thr &&
- fabs(accel_ema[2]) < accel_err_thr )
- return 3; // [ 0, -g, 0 ]
- if ( fabs(accel_ema[0]) < accel_err_thr &&
- fabs(accel_ema[1]) < accel_err_thr &&
- fabs(accel_ema[2] - CONSTANTS_ONE_G) < accel_err_thr )
- return 4; // [ 0, 0, g ]
- if ( fabs(accel_ema[0]) < accel_err_thr &&
- fabs(accel_ema[1]) < accel_err_thr &&
- fabs(accel_ema[2] + CONSTANTS_ONE_G) < accel_err_thr )
- return 5; // [ 0, 0, -g ]
-
- mavlink_log_info(mavlink_fd, "ERROR: invalid orientation");
-
- return -2; // Can't detect orientation
-}
-
-/*
- * Read specified number of accelerometer samples, calculate average and dispersion.
- */
-int read_accelerometer_avg(int sensor_combined_sub, float accel_avg[3], int samples_num) {
- struct pollfd fds[1] = { { .fd = sensor_combined_sub, .events = POLLIN } };
- int count = 0;
- float accel_sum[3] = { 0.0f, 0.0f, 0.0f };
-
- while (count < samples_num) {
- int poll_ret = poll(fds, 1, 1000);
- if (poll_ret == 1) {
- struct sensor_combined_s sensor;
- orb_copy(ORB_ID(sensor_combined), sensor_combined_sub, &sensor);
- for (int i = 0; i < 3; i++)
- accel_sum[i] += sensor.accelerometer_m_s2[i];
- count++;
- } else {
- return ERROR;
- }
- }
-
- for (int i = 0; i < 3; i++) {
- accel_avg[i] = accel_sum[i] / count;
- }
-
- return OK;
-}
-
-int mat_invert3(float src[3][3], float dst[3][3]) {
- float det = src[0][0] * (src[1][1] * src[2][2] - src[1][2] * src[2][1]) -
- src[0][1] * (src[1][0] * src[2][2] - src[1][2] * src[2][0]) +
- src[0][2] * (src[1][0] * src[2][1] - src[1][1] * src[2][0]);
- if (det == 0.0)
- return ERROR; // Singular matrix
-
- dst[0][0] = (src[1][1] * src[2][2] - src[1][2] * src[2][1]) / det;
- dst[1][0] = (src[1][2] * src[2][0] - src[1][0] * src[2][2]) / det;
- dst[2][0] = (src[1][0] * src[2][1] - src[1][1] * src[2][0]) / det;
- dst[0][1] = (src[0][2] * src[2][1] - src[0][1] * src[2][2]) / det;
- dst[1][1] = (src[0][0] * src[2][2] - src[0][2] * src[2][0]) / det;
- dst[2][1] = (src[0][1] * src[2][0] - src[0][0] * src[2][1]) / det;
- dst[0][2] = (src[0][1] * src[1][2] - src[0][2] * src[1][1]) / det;
- dst[1][2] = (src[0][2] * src[1][0] - src[0][0] * src[1][2]) / det;
- dst[2][2] = (src[0][0] * src[1][1] - src[0][1] * src[1][0]) / det;
-
- return OK;
-}
-
-int calculate_calibration_values(float accel_ref[6][3], float accel_T[3][3], float accel_offs[3], float g) {
- /* calculate offsets */
- for (int i = 0; i < 3; i++) {
- accel_offs[i] = (accel_ref[i * 2][i] + accel_ref[i * 2 + 1][i]) / 2;
- }
-
- /* fill matrix A for linear equations system*/
- float mat_A[3][3];
- memset(mat_A, 0, sizeof(mat_A));
- for (int i = 0; i < 3; i++) {
- for (int j = 0; j < 3; j++) {
- float a = accel_ref[i * 2][j] - accel_offs[j];
- mat_A[i][j] = a;
- }
- }
-
- /* calculate inverse matrix for A */
- float mat_A_inv[3][3];
- if (mat_invert3(mat_A, mat_A_inv) != OK)
- return ERROR;
-
- /* copy results to accel_T */
- for (int i = 0; i < 3; i++) {
- for (int j = 0; j < 3; j++) {
- /* simplify matrices mult because b has only one non-zero element == g at index i */
- accel_T[j][i] = mat_A_inv[j][i] * g;
- }
- }
-
- return OK;
-}
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