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Merge pull request #3040 from ChristophTobler/master 

several first changes to INAV optical flow estimation
This commit is contained in:
Roman Bapst 2015-10-29 09:09:55 +01:00
parent 47a20f0dd2 8137a26122
commit ffbb1d30cf
4 changed files with 154 additions and 69 deletions
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2
src/modules/position_estimator_inav/CMakeLists.txt
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@ -31,7 +31,7 @@
#
############################################################################
if(${OS} STREQUAL "nuttx")
list(APPEND MODULE_CFLAGS -Wframe-larger-than=3800)
list(APPEND MODULE_CFLAGS -Wframe-larger-than=3890)
endif()
px4_add_module(
MODULE modules__position_estimator_inav

145
src/modules/position_estimator_inav/position_estimator_inav_main.c
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@ -38,7 +38,6 @@
* @author Anton Babushkin <anton.babushkin@me.com>
* @author Nuno Marques <n.marques21@hotmail.com>
*/
#include <px4_posix.h>
#include <unistd.h>
#include <stdlib.h>
@ -66,6 +65,7 @@
#include <uORB/topics/att_pos_mocap.h>
#include <uORB/topics/home_position.h>
#include <uORB/topics/optical_flow.h>
#include <uORB/topics/distance_sensor.h>
#include <mavlink/mavlink_log.h>
#include <poll.h>
#include <systemlib/err.h>
@ -90,8 +90,8 @@ static const hrt_abstime vision_topic_timeout = 500000; // Vision topic timeout
static const hrt_abstime mocap_topic_timeout = 500000; // Mocap topic timeout = 0.5s
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
static const hrt_abstime lidar_timeout = 150000; // lidar timeout = 150ms
static const hrt_abstime lidar_valid_timeout = 1000000; // estimate lidar distance during this time after lidar loss
static const unsigned updates_counter_len = 1000000;
static const float max_flow = 1.0f; // max flow value that can be used, rad/s
@ -311,19 +311,26 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
{ 0.0f }, // D (pos)
};
float corr_sonar = 0.0f;
float corr_sonar_filtered = 0.0f;
float corr_lidar = 0.0f;
float corr_lidar_filtered = 0.0f;
float corr_flow[] = { 0.0f, 0.0f }; // N E
float w_flow = 0.0f;
float sonar_prev = 0.0f;
float lidar_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)
hrt_abstime sonar_valid_time = 0; // time of last sonar measurement used for correction (filtered)
hrt_abstime lidar_time = 0; // time of last lidar measurement (not filtered)
hrt_abstime lidar_valid_time = 0; // time of last lidar measurement used for correction (filtered)
int n_flow = 0;
float gyro_offset_filtered[] = { 0.0f, 0.0f, 0.0f };
float flow_gyrospeed[] = { 0.0f, 0.0f, 0.0f };
float flow_gyrospeed_filtered[] = { 0.0f, 0.0f, 0.0f };
float att_gyrospeed_filtered[] = { 0.0f, 0.0f, 0.0f };
float yaw_comp[] = { 0.0f, 0.0f };
bool gps_valid = false; // GPS is valid
bool sonar_valid = false; // sonar is valid
bool lidar_valid = false; // lidar is valid
bool flow_valid = false; // flow is valid
bool flow_accurate = false; // flow should be accurate (this flag not updated if flow_valid == false)
bool vision_valid = false; // vision is valid
@ -352,6 +359,8 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
memset(&mocap, 0, sizeof(mocap));
struct vehicle_global_position_s global_pos;
memset(&global_pos, 0, sizeof(global_pos));
struct distance_sensor_s lidar;
memset(&lidar, 0, sizeof(lidar));
/* subscribe */
int parameter_update_sub = orb_subscribe(ORB_ID(parameter_update));
@ -364,6 +373,7 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
int vision_position_estimate_sub = orb_subscribe(ORB_ID(vision_position_estimate));
int att_pos_mocap_sub = orb_subscribe(ORB_ID(att_pos_mocap));
int home_position_sub = orb_subscribe(ORB_ID(home_position));
int distance_sensor_sub = orb_subscribe(ORB_ID(distance_sensor));
/* advertise */
orb_advert_t vehicle_local_position_pub = orb_advertise(ORB_ID(vehicle_local_position), &local_pos);
@ -445,6 +455,7 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
attitude_updates++;
bool updated;
bool updated2;
/* parameter update */
orb_check(parameter_update_sub, &updated);
@ -510,56 +521,60 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
/* optical flow */
orb_check(optical_flow_sub, &updated);
orb_check(distance_sensor_sub, &updated2);
if (updated) {
if (updated && updated2) {
orb_copy(ORB_ID(optical_flow), optical_flow_sub, &flow);
orb_copy(ORB_ID(distance_sensor), distance_sensor_sub, &lidar);
/* calculate time from previous update */
// float flow_dt = flow_prev > 0 ? (flow.flow_timestamp - flow_prev) * 1e-6f : 0.1f;
// flow_prev = flow.flow_timestamp;
if ((flow.ground_distance_m > 0.31f) &&
(flow.ground_distance_m < 4.0f) &&
(PX4_R(att.R, 2, 2) > 0.7f) &&
(fabsf(flow.ground_distance_m - sonar_prev) > FLT_EPSILON)) {
if ((lidar.current_distance > 0.21f) &&
(lidar.current_distance < 4.0f) &&
/*(PX4_R(att.R, 2, 2) > 0.7f) &&*/
(fabsf(lidar.current_distance - lidar_prev) > FLT_EPSILON)) {
sonar_time = t;
sonar_prev = flow.ground_distance_m;
corr_sonar = flow.ground_distance_m + surface_offset + z_est[0];
corr_sonar_filtered += (corr_sonar - corr_sonar_filtered) * params.sonar_filt;
lidar_time = t;
lidar_prev = lidar.current_distance;
corr_lidar = lidar.current_distance + surface_offset + z_est[0];
corr_lidar_filtered += (corr_lidar - corr_lidar_filtered) * params.lidar_filt;
if (fabsf(corr_sonar) > params.sonar_err) {
if (fabsf(corr_lidar) > params.lidar_err) {
/* correction is too large: spike or new ground level? */
if (fabsf(corr_sonar - corr_sonar_filtered) > params.sonar_err) {
if (fabsf(corr_lidar - corr_lidar_filtered) > params.lidar_err) {
/* spike detected, ignore */
corr_sonar = 0.0f;
sonar_valid = false;
corr_lidar = 0.0f;
lidar_valid = false;
} else {
/* new ground level */
surface_offset -= corr_sonar;
surface_offset -= corr_lidar;
surface_offset_rate = 0.0f;
corr_sonar = 0.0f;
corr_sonar_filtered = 0.0f;
sonar_valid_time = t;
sonar_valid = true;
corr_lidar = 0.0f;
corr_lidar_filtered = 0.0f;
lidar_valid_time = t;
lidar_valid = true;
local_pos.surface_bottom_timestamp = t;
mavlink_log_info(mavlink_fd, "[inav] new surface level: %d", (int)surface_offset);
}
} else {
/* correction is ok, use it */
sonar_valid_time = t;
sonar_valid = true;
lidar_valid_time = t;
lidar_valid = true;
}
}
float flow_q = flow.quality / 255.0f;
float dist_bottom = - z_est[0] - surface_offset;
float dist_bottom = - z_est[0] - surface_offset; //lidar.current_distance;
if (dist_bottom > 0.3f && flow_q > params.flow_q_min && (t < sonar_valid_time + sonar_valid_timeout) && PX4_R(att.R, 2, 2) > 0.7f) {
if (dist_bottom > 0.21f && flow_q > params.flow_q_min) {
/* distance to surface */
float flow_dist = dist_bottom / PX4_R(att.R, 2, 2);
//float flow_dist = dist_bottom / PX4_R(att.R, 2, 2); //use this if using sonar
float flow_dist = dist_bottom; //use this if using lidar
/* check if flow if too large for accurate measurements */
/* calculate estimated velocity in body frame */
float body_v_est[2] = { 0.0f, 0.0f };
@ -571,12 +586,48 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
/* set this flag if flow should be accurate according to current velocity and attitude rate estimate */
flow_accurate = fabsf(body_v_est[1] / flow_dist - att.rollspeed) < max_flow &&
fabsf(body_v_est[0] / flow_dist + att.pitchspeed) < max_flow;
//this flag is not working -->
flow_accurate = true; //already checked if flow_q > 0.3
/*calculate offset of flow-gyro using already calibrated gyro from autopilot*/
flow_gyrospeed[0] = flow.gyro_x_rate_integral/(float)flow.integration_timespan*1000000.0f;
flow_gyrospeed[1] = flow.gyro_y_rate_integral/(float)flow.integration_timespan*1000000.0f;
flow_gyrospeed[2] = flow.gyro_z_rate_integral/(float)flow.integration_timespan*1000000.0f;
//moving average
if (n_flow >= 100) {
gyro_offset_filtered[0] = flow_gyrospeed_filtered[0] - att_gyrospeed_filtered[0];
gyro_offset_filtered[1] = flow_gyrospeed_filtered[1] - att_gyrospeed_filtered[1];
gyro_offset_filtered[2] = flow_gyrospeed_filtered[2] - att_gyrospeed_filtered[2];
n_flow = 0;
flow_gyrospeed_filtered[0] = 0.0f;
flow_gyrospeed_filtered[1] = 0.0f;
flow_gyrospeed_filtered[2] = 0.0f;
att_gyrospeed_filtered[0] = 0.0f;
att_gyrospeed_filtered[1] = 0.0f;
att_gyrospeed_filtered[2] = 0.0f;
} else {
flow_gyrospeed_filtered[0] = (flow_gyrospeed[0] + n_flow * flow_gyrospeed_filtered[0]) / (n_flow + 1);
flow_gyrospeed_filtered[1] = (flow_gyrospeed[1] + n_flow * flow_gyrospeed_filtered[1]) / (n_flow + 1);
flow_gyrospeed_filtered[2] = (flow_gyrospeed[2] + n_flow * flow_gyrospeed_filtered[2]) / (n_flow + 1);
att_gyrospeed_filtered[0] = (att.pitchspeed + n_flow * att_gyrospeed_filtered[0]) / (n_flow + 1);
att_gyrospeed_filtered[1] = (att.rollspeed + n_flow * att_gyrospeed_filtered[1]) / (n_flow + 1);
att_gyrospeed_filtered[2] = (att.yawspeed + n_flow * att_gyrospeed_filtered[2]) / (n_flow + 1);
n_flow++;
}
/*yaw compensation (flow sensor is not in center of rotation) -> params in QGC*/
yaw_comp[0] = params.flow_module_offset_x * (flow_gyrospeed[2] - gyro_offset_filtered[2]);
yaw_comp[1] = - params.flow_module_offset_y * (flow_gyrospeed[2] - gyro_offset_filtered[2]);
/* convert raw flow to angular flow (rad/s) */
float flow_ang[2];
//todo check direction of x und y axis
flow_ang[0] = flow.pixel_flow_x_integral/(float)flow.integration_timespan*1000000.0f;//flow.flow_raw_x * params.flow_k / 1000.0f / flow_dt;
flow_ang[1] = flow.pixel_flow_y_integral/(float)flow.integration_timespan*1000000.0f;//flow.flow_raw_y * params.flow_k / 1000.0f / flow_dt;
//calculate flow [rad/s] and compensate for rotations (and offset of flow-gyro)
flow_ang[0] = (flow.pixel_flow_x_integral - flow.gyro_x_rate_integral)/(float)flow.integration_timespan*1000000.0f + gyro_offset_filtered[0] - yaw_comp[0];//flow.flow_raw_x * params.flow_k / 1000.0f / flow_dt;
flow_ang[1] = (flow.pixel_flow_y_integral - flow.gyro_y_rate_integral)/(float)flow.integration_timespan*1000000.0f + gyro_offset_filtered[1] - yaw_comp[1];//flow.flow_raw_y * params.flow_k / 1000.0f / flow_dt;
/* flow measurements vector */
float flow_m[3];
flow_m[0] = -flow_ang[0] * flow_dist;
@ -599,6 +650,7 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
float flow_q_weight = (flow_q - params.flow_q_min) / (1.0f - params.flow_q_min);
w_flow = PX4_R(att.R, 2, 2) * flow_q_weight / fmaxf(1.0f, flow_dist);
/* if flow is not accurate, reduce weight for it */
// TODO make this more fuzzy
if (!flow_accurate) {
@ -862,9 +914,9 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
}
/* check for timeout on FLOW topic */
if ((flow_valid || sonar_valid) && t > flow.timestamp + flow_topic_timeout) {
if ((flow_valid || lidar_valid) && t > flow.timestamp + flow_topic_timeout) {
flow_valid = false;
sonar_valid = false;
lidar_valid = false;
warnx("FLOW timeout");
mavlink_log_info(mavlink_fd, "[inav] FLOW timeout");
}
@ -890,10 +942,10 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
mavlink_log_info(mavlink_fd, "[inav] MOCAP timeout");
}
/* check for sonar measurement timeout */
if (sonar_valid && (t > (sonar_time + sonar_timeout))) {
corr_sonar = 0.0f;
sonar_valid = false;
/* check for lidar measurement timeout */
if (lidar_valid && (t > (lidar_time + lidar_timeout))) {
corr_lidar = 0.0f;
lidar_valid = false;
}
float dt = t_prev > 0 ? (t - t_prev) / 1000000.0f : 0.0f;
@ -921,16 +973,16 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
bool can_estimate_xy = (eph < max_eph_epv) || use_gps_xy || use_flow || use_vision_xy || use_mocap;
bool dist_bottom_valid = (t < sonar_valid_time + sonar_valid_timeout);
bool dist_bottom_valid = (t < lidar_valid_time + lidar_valid_timeout);
if (dist_bottom_valid) {
/* surface distance prediction */
surface_offset += surface_offset_rate * dt;
/* surface distance correction */
if (sonar_valid) {
surface_offset_rate -= corr_sonar * 0.5f * params.w_z_sonar * params.w_z_sonar * dt;
surface_offset -= corr_sonar * params.w_z_sonar * dt;
if (lidar_valid) {
surface_offset_rate -= corr_lidar * 0.5f * params.w_z_lidar * params.w_z_lidar * dt;
surface_offset -= corr_lidar * params.w_z_lidar * dt;
}
}
@ -1114,6 +1166,7 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
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);
//mavlink_log_info(mavlink_fd, "w_flow = %2.4f\t w_xy_flow = %2.4f\n", (double)w_flow, (double)params.w_xy_flow);
}
if (use_gps_xy) {
@ -1229,7 +1282,7 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
if (local_pos.dist_bottom_valid) {
local_pos.dist_bottom = -z_est[0] - surface_offset;
local_pos.dist_bottom_rate = -z_est[1] - surface_offset_rate;
local_pos.dist_bottom_rate = - z_est[1] - surface_offset_rate;
}
local_pos.timestamp = t;

60
src/modules/position_estimator_inav/position_estimator_inav_params.c
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@ -86,15 +86,15 @@ PARAM_DEFINE_FLOAT(INAV_W_Z_GPS_V, 0.0f);
PARAM_DEFINE_FLOAT(INAV_W_Z_VIS_P, 5.0f);
/**
* Z axis weight for sonar
* Z axis weight for lidar
*
* Weight (cutoff frequency) for sonar measurements.
* Weight (cutoff frequency) for lidar measurements.
*
* @min 0.0
* @max 10.0
* @group Position Estimator INAV
*/
PARAM_DEFINE_FLOAT(INAV_W_Z_SONAR, 3.0f);
PARAM_DEFINE_FLOAT(INAV_W_Z_LIDAR, 3.0f);
/**
* XY axis weight for GPS position
@ -158,10 +158,10 @@ PARAM_DEFINE_FLOAT(INAV_W_XY_VIS_V, 0.0f);
* Weight (cutoff frequency) for optical flow (velocity) measurements.
*
* @min 0.0
* @max 10.0
* @max 30.0
* @group Position Estimator INAV
*/
PARAM_DEFINE_FLOAT(INAV_W_XY_FLOW, 5.0f);
PARAM_DEFINE_FLOAT(INAV_W_XY_FLOW, 10.0f);
/**
* XY axis weight for resetting velocity
@ -217,18 +217,18 @@ PARAM_DEFINE_FLOAT(INAV_FLOW_K, 0.15f);
* @max 1.0
* @group Position Estimator INAV
*/
PARAM_DEFINE_FLOAT(INAV_FLOW_Q_MIN, 0.5f);
PARAM_DEFINE_FLOAT(INAV_FLOW_Q_MIN, 0.3f);
/**
* Weight for sonar filter
* Weight for lidar filter
*
* Sonar filter detects spikes on sonar measurements and used to detect new surface level.
* Lidar filter detects spikes on lidar measurements and used to detect new surface level.
*
* @min 0.0
* @max 1.0
* @group Position Estimator INAV
*/
PARAM_DEFINE_FLOAT(INAV_SONAR_FILT, 0.05f);
PARAM_DEFINE_FLOAT(INAV_LIDAR_FILT, 0.05f);
/**
* Sonar maximal error for new surface
@ -240,7 +240,7 @@ PARAM_DEFINE_FLOAT(INAV_SONAR_FILT, 0.05f);
* @unit m
* @group Position Estimator INAV
*/
PARAM_DEFINE_FLOAT(INAV_SONAR_ERR, 0.5f);
PARAM_DEFINE_FLOAT(INAV_LIDAR_ERR, 0.5f);
/**
* Land detector time
@ -289,6 +289,30 @@ PARAM_DEFINE_FLOAT(INAV_LAND_THR, 0.2f);
*/
PARAM_DEFINE_FLOAT(INAV_DELAY_GPS, 0.2f);
/**
* Flow module offset (center of rotation) in X direction
*
* Yaw X flow compensation
*
* @min -1.0
* @max 1.0
* @unit m
* @group Position Estimator INAV
*/
PARAM_DEFINE_FLOAT(INAV_FLOW_DIST_X, 0.0f);
/**
* Flow module offset (center of rotation) in Y direction
*
* Yaw Y flow compensation
*
* @min -1.0
* @max 1.0
* @unit m
* @group Position Estimator INAV
*/
PARAM_DEFINE_FLOAT(INAV_FLOW_DIST_Y, 0.0f);
/**
* Disable vision input
*
@ -319,7 +343,7 @@ int inav_parameters_init(struct position_estimator_inav_param_handles *h)
h->w_z_gps_p = param_find("INAV_W_Z_GPS_P");
h->w_z_gps_v = param_find("INAV_W_Z_GPS_V");
h->w_z_vision_p = param_find("INAV_W_Z_VIS_P");
h->w_z_sonar = param_find("INAV_W_Z_SONAR");
h->w_z_lidar = param_find("INAV_W_Z_LIDAR");
h->w_xy_gps_p = param_find("INAV_W_XY_GPS_P");
h->w_xy_gps_v = param_find("INAV_W_XY_GPS_V");
h->w_xy_vision_p = param_find("INAV_W_XY_VIS_P");
@ -331,13 +355,15 @@ int inav_parameters_init(struct position_estimator_inav_param_handles *h)
h->w_acc_bias = param_find("INAV_W_ACC_BIAS");
h->flow_k = param_find("INAV_FLOW_K");
h->flow_q_min = param_find("INAV_FLOW_Q_MIN");
h->sonar_filt = param_find("INAV_SONAR_FILT");
h->sonar_err = param_find("INAV_SONAR_ERR");
h->lidar_filt = param_find("INAV_LIDAR_FILT");
h->lidar_err = param_find("INAV_LIDAR_ERR");
h->land_t = param_find("INAV_LAND_T");
h->land_disp = param_find("INAV_LAND_DISP");
h->land_thr = param_find("INAV_LAND_THR");
h->no_vision = param_find("CBRK_NO_VISION");
h->delay_gps = param_find("INAV_DELAY_GPS");
h->flow_module_offset_x = param_find("INAV_FLOW_DIST_X");
h->flow_module_offset_y = param_find("INAV_FLOW_DIST_Y");
return 0;
}
@ -347,7 +373,7 @@ int inav_parameters_update(const struct position_estimator_inav_param_handles *h
param_get(h->w_z_baro, &(p->w_z_baro));
param_get(h->w_z_gps_p, &(p->w_z_gps_p));
param_get(h->w_z_vision_p, &(p->w_z_vision_p));
param_get(h->w_z_sonar, &(p->w_z_sonar));
param_get(h->w_z_lidar, &(p->w_z_lidar));
param_get(h->w_xy_gps_p, &(p->w_xy_gps_p));
param_get(h->w_xy_gps_v, &(p->w_xy_gps_v));
param_get(h->w_xy_vision_p, &(p->w_xy_vision_p));
@ -359,13 +385,15 @@ int inav_parameters_update(const struct position_estimator_inav_param_handles *h
param_get(h->w_acc_bias, &(p->w_acc_bias));
param_get(h->flow_k, &(p->flow_k));
param_get(h->flow_q_min, &(p->flow_q_min));
param_get(h->sonar_filt, &(p->sonar_filt));
param_get(h->sonar_err, &(p->sonar_err));
param_get(h->lidar_filt, &(p->lidar_filt));
param_get(h->lidar_err, &(p->lidar_err));
param_get(h->land_t, &(p->land_t));
param_get(h->land_disp, &(p->land_disp));
param_get(h->land_thr, &(p->land_thr));
param_get(h->no_vision, &(p->no_vision));
param_get(h->delay_gps, &(p->delay_gps));
param_get(h->flow_module_offset_x, &(p->flow_module_offset_x));
param_get(h->flow_module_offset_y, &(p->flow_module_offset_y));
return 0;
}

16
src/modules/position_estimator_inav/position_estimator_inav_params.h
View File

@ -46,7 +46,7 @@ struct position_estimator_inav_params {
float w_z_gps_p;
float w_z_gps_v;
float w_z_vision_p;
float w_z_sonar;
float w_z_lidar;
float w_xy_gps_p;
float w_xy_gps_v;
float w_xy_vision_p;
@ -58,13 +58,15 @@ struct position_estimator_inav_params {
float w_acc_bias;
float flow_k;
float flow_q_min;
float sonar_filt;
float sonar_err;
float lidar_filt;
float lidar_err;
float land_t;
float land_disp;
float land_thr;
int32_t no_vision;
float delay_gps;
float flow_module_offset_x;
float flow_module_offset_y;
};
struct position_estimator_inav_param_handles {
@ -72,7 +74,7 @@ struct position_estimator_inav_param_handles {
param_t w_z_gps_p;
param_t w_z_gps_v;
param_t w_z_vision_p;
param_t w_z_sonar;
param_t w_z_lidar;
param_t w_xy_gps_p;
param_t w_xy_gps_v;
param_t w_xy_vision_p;
@ -84,13 +86,15 @@ struct position_estimator_inav_param_handles {
param_t w_acc_bias;
param_t flow_k;
param_t flow_q_min;
param_t sonar_filt;
param_t sonar_err;
param_t lidar_filt;
param_t lidar_err;
param_t land_t;
param_t land_disp;
param_t land_thr;
param_t no_vision;
param_t delay_gps;
param_t flow_module_offset_x;
param_t flow_module_offset_y;
};
#define CBRK_NO_VISION_KEY 328754