ardupilot/libraries/AP_RangeFinder/RangeFinder_Backend.cpp

107 lines
3.8 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_Common/AP_Common.h>
#include <AP_HAL/AP_HAL.h>
#include "RangeFinder.h"
#include "RangeFinder_Backend.h"
extern const AP_HAL::HAL& hal;
/*
base class constructor.
This incorporates initialisation as well.
*/
AP_RangeFinder_Backend::AP_RangeFinder_Backend(RangeFinder::RangeFinder_State &_state, AP_RangeFinder_Params &_params) :
state(_state),
params(_params)
{
}
MAV_DISTANCE_SENSOR AP_RangeFinder_Backend::get_mav_distance_sensor_type() const {
if (params.type == RangeFinder::RangeFinder_TYPE_NONE) {
return MAV_DISTANCE_SENSOR_UNKNOWN;
}
return _get_mav_distance_sensor_type();
}
RangeFinder::RangeFinder_Status AP_RangeFinder_Backend::status() const {
if (params.type == RangeFinder::RangeFinder_TYPE_NONE) {
// turned off at runtime?
return RangeFinder::RangeFinder_NotConnected;
}
return state.status;
}
// true if sensor is returning data
bool AP_RangeFinder_Backend::has_data() const {
return ((state.status != RangeFinder::RangeFinder_NotConnected) &&
(state.status != RangeFinder::RangeFinder_NoData));
}
// update status based on distance measurement
void AP_RangeFinder_Backend::update_status()
{
// check distance
if ((int16_t)state.distance_cm > params.max_distance_cm) {
set_status(RangeFinder::RangeFinder_OutOfRangeHigh);
} else if ((int16_t)state.distance_cm < params.min_distance_cm) {
set_status(RangeFinder::RangeFinder_OutOfRangeLow);
} else {
set_status(RangeFinder::RangeFinder_Good);
}
}
// set status and update valid count
void AP_RangeFinder_Backend::set_status(RangeFinder::RangeFinder_Status _status)
{
state.status = _status;
// update valid count
if (_status == RangeFinder::RangeFinder_Good) {
if (state.range_valid_count < 10) {
state.range_valid_count++;
}
} else {
state.range_valid_count = 0;
}
}
/*
set pre-arm checks to passed if the range finder has been exercised through a reasonable range of movement
max distance sensed is at least 50cm > min distance sensed
max distance < 200cm
min distance sensed is within 10cm of ground clearance or sensor's minimum distance
*/
void AP_RangeFinder_Backend::update_pre_arm_check()
{
// return immediately if already passed or no sensor data
if (state.pre_arm_check || state.status == RangeFinder::RangeFinder_NotConnected || state.status == RangeFinder::RangeFinder_NoData) {
return;
}
// update min, max captured distances
state.pre_arm_distance_min = MIN(state.distance_cm, state.pre_arm_distance_min);
state.pre_arm_distance_max = MAX(state.distance_cm, state.pre_arm_distance_max);
// Check that the range finder has been exercised through a realistic range of movement
if (((state.pre_arm_distance_max - state.pre_arm_distance_min) >= RANGEFINDER_PREARM_REQUIRED_CHANGE_CM) &&
(state.pre_arm_distance_max < RANGEFINDER_PREARM_ALT_MAX_CM) &&
((int16_t)state.pre_arm_distance_min < (MAX(params.ground_clearance_cm,params.min_distance_cm) + 10)) &&
((int16_t)state.pre_arm_distance_min > (MIN(params.ground_clearance_cm,params.min_distance_cm) - 10))) {
state.pre_arm_check = true;
}
}