ardupilot/libraries/AP_Proximity/AP_Proximity_MAV.cpp

159 lines
6.3 KiB
C++

/*
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 <http://www.gnu.org/licenses/>.
*/
#include <AP_HAL/AP_HAL.h>
#include "AP_Proximity_MAV.h"
#include <ctype.h>
#include <stdio.h>
extern const AP_HAL::HAL& hal;
#define PROXIMITY_MAV_TIMEOUT_MS 500 // distance messages must arrive within this many milliseconds
// update the state of the sensor
void AP_Proximity_MAV::update(void)
{
// check for timeout and set health status
if ((_last_update_ms == 0 || (AP_HAL::millis() - _last_update_ms > PROXIMITY_MAV_TIMEOUT_MS)) &&
(_last_upward_update_ms == 0 || (AP_HAL::millis() - _last_upward_update_ms > PROXIMITY_MAV_TIMEOUT_MS))) {
set_status(AP_Proximity::Status::NoData);
} else {
set_status(AP_Proximity::Status::Good);
}
}
// get distance upwards in meters. returns true on success
bool AP_Proximity_MAV::get_upward_distance(float &distance) const
{
if ((_last_upward_update_ms != 0) && (AP_HAL::millis() - _last_upward_update_ms <= PROXIMITY_MAV_TIMEOUT_MS)) {
distance = _distance_upward;
return true;
}
return false;
}
// handle mavlink DISTANCE_SENSOR messages
void AP_Proximity_MAV::handle_msg(const mavlink_message_t &msg)
{
if (msg.msgid == MAVLINK_MSG_ID_DISTANCE_SENSOR) {
mavlink_distance_sensor_t packet;
mavlink_msg_distance_sensor_decode(&msg, &packet);
// store distance to appropriate sector based on orientation field
if (packet.orientation <= MAV_SENSOR_ROTATION_YAW_315) {
uint8_t sector = packet.orientation;
_angle[sector] = sector * 45;
_distance[sector] = packet.current_distance * 0.01f;
_distance_min = packet.min_distance * 0.01f;
_distance_max = packet.max_distance * 0.01f;
_distance_valid[sector] = (_distance[sector] >= _distance_min) && (_distance[sector] <= _distance_max);
_last_update_ms = AP_HAL::millis();
update_boundary_for_sector(sector, true);
}
// store upward distance
if (packet.orientation == MAV_SENSOR_ROTATION_PITCH_90) {
_distance_upward = packet.current_distance * 0.01f;
_last_upward_update_ms = AP_HAL::millis();
}
return;
}
if (msg.msgid == MAVLINK_MSG_ID_OBSTACLE_DISTANCE) {
mavlink_obstacle_distance_t packet;
mavlink_msg_obstacle_distance_decode(&msg, &packet);
// check increment (message's sector width)
float increment;
if (!is_zero(packet.increment_f)) {
// use increment float
increment = packet.increment_f;
} else if (packet.increment != 0) {
// use increment uint8_t
increment = packet.increment;
} else {
// invalid increment
return;
}
const float MAX_DISTANCE = 9999.0f;
const uint8_t total_distances = MIN(((360.0f / fabsf(increment)) + 0.5f), MAVLINK_MSG_OBSTACLE_DISTANCE_FIELD_DISTANCES_LEN); // usually 72
// set distance min and max
_distance_min = packet.min_distance * 0.01f;
_distance_max = packet.max_distance * 0.01f;
_last_update_ms = AP_HAL::millis();
// get user configured yaw correction from front end
const float param_yaw_offset = constrain_float(frontend.get_yaw_correction(state.instance), -360.0f, +360.0f);
const float yaw_correction = wrap_360(param_yaw_offset + packet.angle_offset);
if (frontend.get_orientation(state.instance) != 0) {
increment *= -1;
}
Vector2f current_pos;
float current_heading;
const bool database_ready = database_prepare_for_push(current_pos, current_heading);
// initialise updated array and proximity sector angles (to closest object) and distances
bool sector_updated[PROXIMITY_NUM_SECTORS];
for (uint8_t i = 0; i < PROXIMITY_NUM_SECTORS; i++) {
sector_updated[i] = false;
_angle[i] = _sector_middle_deg[i];
_distance[i] = MAX_DISTANCE;
}
// iterate over message's sectors
for (uint8_t j = 0; j < total_distances; j++) {
const uint16_t distance_cm = packet.distances[j];
if (distance_cm == 0 ||
distance_cm == 65535 ||
distance_cm < packet.min_distance ||
distance_cm > packet.max_distance)
{
// sanity check failed, ignore this distance value
continue;
}
const float packet_distance_m = distance_cm * 0.01f;
const float mid_angle = wrap_360((float)j * increment + yaw_correction);
// iterate over proximity sectors
for (uint8_t i = 0; i < PROXIMITY_NUM_SECTORS; i++) {
float angle_diff = fabsf(wrap_180(_sector_middle_deg[i] - mid_angle));
// update distance array sector with shortest distance from message
if ((angle_diff <= (PROXIMITY_SECTOR_WIDTH_DEG * 0.5f)) && (packet_distance_m < _distance[i])) {
_distance[i] = packet_distance_m;
_angle[i] = mid_angle;
sector_updated[i] = true;
}
}
// update Object Avoidance database with Earth-frame point
if (database_ready) {
database_push(mid_angle, packet_distance_m, _last_update_ms, current_pos, current_heading);
}
}
// update proximity sectors validity and boundary point
for (uint8_t i = 0; i < PROXIMITY_NUM_SECTORS; i++) {
_distance_valid[i] = (_distance[i] >= _distance_min) && (_distance[i] <= _distance_max);
if (sector_updated[i]) {
update_boundary_for_sector(i, false);
}
}
}
}