position_estimator_inav: more safe EPH/EPV estimation, minor changes

This commit is contained in:
Anton Babushkin 2014-05-31 16:19:38 +02:00
parent 612b25711f
commit 6b8248ee29
1 changed files with 30 additions and 17 deletions

View File

@ -79,7 +79,7 @@ static bool thread_running = false; /**< Deamon status flag */
static int position_estimator_inav_task; /**< Handle of deamon task / thread */
static bool verbose_mode = false;
static const hrt_abstime gps_topic_timeout = 1000000; // GPS topic timeout = 1s
static const hrt_abstime gps_topic_timeout = 500000; // GPS topic timeout = 0.5s
static const hrt_abstime flow_topic_timeout = 1000000; // optical flow topic timeout = 1s
static const hrt_abstime sonar_timeout = 150000; // sonar timeout = 150ms
static const hrt_abstime sonar_valid_timeout = 1000000; // estimate sonar distance during this time after sonar loss
@ -218,8 +218,13 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
memset(R_gps, 0, sizeof(R_gps));
int buf_ptr = 0;
float eph = 1.0;
float epv = 1.0;
static const float min_eph_epv = 2.0f; // min EPH/EPV, used for weight calculation
static const float max_eph_epv = 20.0f; // max EPH/EPV acceptable for estimation
float eph = max_eph_epv;
float epv = 1.0f;
float eph_flow = 1.0f;
float x_est_prev[2], y_est_prev[2], z_est_prev[2];
memset(x_est_prev, 0, sizeof(x_est_prev));
@ -276,9 +281,6 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
float corr_flow[] = { 0.0f, 0.0f }; // N E
float w_flow = 0.0f;
static float min_eph_epv = 2.0f; // min EPH/EPV, used for weight calculation
static float max_eph_epv = 10.0f; // max EPH/EPV acceptable for estimation
float sonar_prev = 0.0f;
hrt_abstime flow_prev = 0; // time of last flow measurement
hrt_abstime sonar_time = 0; // time of last sonar measurement (not filtered)
@ -555,9 +557,10 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
w_flow *= 0.05f;
}
flow_valid = true;
/* under ideal conditions, on 1m distance assume EPH = 10cm */
eph_flow = 0.1 / w_flow;
eph = fminf(eph, 0.1 / att.R[2][2] / flow_q * fmaxf(1.0f, flow_dist)); // under ideal conditions, on 1m distance assume EPH = 10cm
flow_valid = true;
} else {
w_flow = 0.0f;
@ -616,13 +619,13 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
/* hysteresis for GPS quality */
if (gps_valid) {
if (gps.eph_m > max_eph_epv * 1.5f || gps.epv_m > max_eph_epv * 1.5f || gps.fix_type < 3) {
if (gps.eph_m > max_eph_epv || gps.epv_m > max_eph_epv || gps.fix_type < 3) {
gps_valid = false;
mavlink_log_info(mavlink_fd, "[inav] GPS signal lost");
}
} else {
if (gps.eph_m < max_eph_epv && gps.epv_m < max_eph_epv && gps.fix_type >= 3) {
if (gps.eph_m < max_eph_epv * 0.7f && gps.epv_m < max_eph_epv * 0.7f && gps.fix_type >= 3) {
gps_valid = true;
reset_est = true;
mavlink_log_info(mavlink_fd, "[inav] GPS signal found");
@ -702,9 +705,6 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
/* save rotation matrix at this moment */
memcpy(R_gps, R_buf[est_i], sizeof(R_gps));
eph = fminf(eph, gps.eph_m);
epv = fminf(epv, gps.epv_m);
w_gps_xy = min_eph_epv / fmaxf(min_eph_epv, gps.eph_m);
w_gps_z = min_eph_epv / fmaxf(min_eph_epv, gps.epv_m);
}
@ -745,8 +745,12 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
t_prev = t;
/* increase EPH/EPV on each step */
eph *= 1.0 + dt;
epv += 0.005 * dt; // add 1m to EPV each 200s (baro drift)
if (eph < max_eph_epv) {
eph *= 1.0 + dt;
}
if (epv < max_eph_epv) {
epv += 0.005 * dt; // add 1m to EPV each 200s (baro drift)
}
/* use GPS if it's valid and reference position initialized */
bool use_gps_xy = ref_inited && gps_valid && params.w_xy_gps_p > MIN_VALID_W;
@ -759,7 +763,7 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
xy_src_time = t;
}
bool can_estimate_xy = eph < max_eph_epv * 1.5;
bool can_estimate_xy = (eph < max_eph_epv) || use_gps_xy || use_flow;
bool dist_bottom_valid = (t < sonar_valid_time + sonar_valid_timeout);
@ -853,7 +857,12 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
/* inertial filter correction for altitude */
inertial_filter_correct(corr_baro, dt, z_est, 0, params.w_z_baro);
inertial_filter_correct(corr_gps[2][0], dt, z_est, 0, w_z_gps_p);
if (use_gps_z) {
epv = fminf(epv, gps.epv_m);
inertial_filter_correct(corr_gps[2][0], dt, z_est, 0, w_z_gps_p);
}
if (!(isfinite(z_est[0]) && isfinite(z_est[1]))) {
write_debug_log("BAD ESTIMATE AFTER Z CORRECTION", dt, x_est, y_est, z_est, x_est_prev, y_est_prev, z_est_prev, acc, corr_gps, w_xy_gps_p, w_xy_gps_v);
@ -878,11 +887,15 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
/* inertial filter correction for position */
if (use_flow) {
eph = fminf(eph, eph_flow);
inertial_filter_correct(corr_flow[0], dt, x_est, 1, params.w_xy_flow * w_flow);
inertial_filter_correct(corr_flow[1], dt, y_est, 1, params.w_xy_flow * w_flow);
}
if (use_gps_xy) {
eph = fminf(eph, gps.eph_m);
inertial_filter_correct(corr_gps[0][0], dt, x_est, 0, w_xy_gps_p);
inertial_filter_correct(corr_gps[1][0], dt, y_est, 0, w_xy_gps_p);