ardupilot/libraries/AP_Proximity/AP_Proximity_LightWareSF40C...

443 lines
14 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_LightWareSF40C.h"
#include <AP_SerialManager/AP_SerialManager.h>
#include <ctype.h>
#include <stdio.h>
extern const AP_HAL::HAL& hal;
/*
The constructor also initialises the proximity sensor. Note that this
constructor is not called until detect() returns true, so we
already know that we should setup the proximity sensor
*/
AP_Proximity_LightWareSF40C::AP_Proximity_LightWareSF40C(AP_Proximity &_frontend,
AP_Proximity::Proximity_State &_state,
AP_SerialManager &serial_manager) :
AP_Proximity_Backend(_frontend, _state)
{
uart = serial_manager.find_serial(AP_SerialManager::SerialProtocol_Lidar360, 0);
if (uart != nullptr) {
uart->begin(serial_manager.find_baudrate(AP_SerialManager::SerialProtocol_Lidar360, 0));
}
}
// detect if a Lightware proximity sensor is connected by looking for a configured serial port
bool AP_Proximity_LightWareSF40C::detect(AP_SerialManager &serial_manager)
{
return serial_manager.find_serial(AP_SerialManager::SerialProtocol_Lidar360, 0) != nullptr;
}
// update the state of the sensor
void AP_Proximity_LightWareSF40C::update(void)
{
if (uart == nullptr) {
return;
}
// initialise sensor if necessary
bool initialised = initialise();
// process incoming messages
check_for_reply();
// request new data from sensor
if (initialised) {
request_new_data();
}
// check for timeout and set health status
if ((_last_distance_received_ms == 0) || (AP_HAL::millis() - _last_distance_received_ms > PROXIMITY_SF40C_TIMEOUT_MS)) {
set_status(AP_Proximity::Proximity_NoData);
} else {
set_status(AP_Proximity::Proximity_Good);
}
}
// get maximum and minimum distances (in meters) of primary sensor
float AP_Proximity_LightWareSF40C::distance_max() const
{
return 100.0f;
}
float AP_Proximity_LightWareSF40C::distance_min() const
{
return 0.20f;
}
// initialise sensor (returns true if sensor is succesfully initialised)
bool AP_Proximity_LightWareSF40C::initialise()
{
// set motor direction once per second
if (_motor_direction > 1) {
if ((_last_request_ms == 0) || AP_HAL::millis() - _last_request_ms > 1000) {
set_motor_direction();
}
}
// set forward direction once per second
if (_forward_direction != frontend.get_yaw_correction(state.instance)) {
if ((_last_request_ms == 0) || AP_HAL::millis() - _last_request_ms > 1000) {
set_forward_direction();
}
}
// request motors turn on once per second
if (_motor_speed == 0) {
if ((_last_request_ms == 0) || AP_HAL::millis() - _last_request_ms > 1000) {
set_motor_speed(true);
}
return false;
}
// initialise sectors
if (!_sector_initialised) {
init_sectors();
return false;
}
return true;
}
// initialise sector angles using user defined ignore areas
void AP_Proximity_LightWareSF40C::init_sectors()
{
// use defaults if no ignore areas defined
uint8_t ignore_area_count = get_ignore_area_count();
if (ignore_area_count == 0) {
_sector_initialised = true;
return;
}
uint8_t sector = 0;
for (uint8_t i=0; i<ignore_area_count; i++) {
// get ignore area info
uint16_t ign_area_angle;
uint8_t ign_area_width;
if (get_ignore_area(i, ign_area_angle, ign_area_width)) {
// calculate how many degrees of space we have between this end of this ignore area and the start of the end
int16_t start_angle, end_angle;
get_next_ignore_start_or_end(1, ign_area_angle, start_angle);
get_next_ignore_start_or_end(0, start_angle, end_angle);
int16_t degrees_to_fill = wrap_360(end_angle - start_angle);
// divide up the area into sectors
while ((degrees_to_fill > 0) && (sector < PROXIMITY_SECTORS_MAX)) {
uint16_t sector_size;
if (degrees_to_fill >= 90) {
// set sector to maximum of 45 degrees
sector_size = 45;
} else if (degrees_to_fill > 45) {
// use half the remaining area to optimise size of this sector and the next
sector_size = degrees_to_fill / 2.0f;
} else {
// 45 degrees or less are left so put it all into the next sector
sector_size = degrees_to_fill;
}
// record the sector middle and width
_sector_middle_deg[sector] = wrap_360(start_angle + sector_size / 2.0f);
_sector_width_deg[sector] = sector_size;
// move onto next sector
start_angle += sector_size;
sector++;
degrees_to_fill -= sector_size;
}
}
}
// set num sectors
_num_sectors = sector;
// re-initialise boundary because sector locations have changed
init_boundary();
// record success
_sector_initialised = true;
}
// set speed of rotating motor
void AP_Proximity_LightWareSF40C::set_motor_speed(bool on_off)
{
// exit immediately if no uart
if (uart == nullptr) {
return;
}
// set motor update speed
if (on_off) {
uart->write("#MBS,3\r\n"); // send request to spin motor at 4.5hz
} else {
uart->write("#MBS,0\r\n"); // send request to stop motor
}
// request update motor speed
uart->write("?MBS\r\n");
_last_request_type = RequestType_MotorSpeed;
_last_request_ms = AP_HAL::millis();
}
// set spin direction of motor
void AP_Proximity_LightWareSF40C::set_motor_direction()
{
// exit immediately if no uart
if (uart == nullptr) {
return;
}
// set motor update speed
if (frontend.get_orientation(state.instance) == 0) {
uart->write("#MBD,0\r\n"); // spin clockwise
} else {
uart->write("#MBD,1\r\n"); // spin counter clockwise
}
// request update on motor direction
uart->write("?MBD\r\n");
_last_request_type = RequestType_MotorDirection;
_last_request_ms = AP_HAL::millis();
}
// set forward direction (to allow rotating lidar)
void AP_Proximity_LightWareSF40C::set_forward_direction()
{
// exit immediately if no uart
if (uart == nullptr) {
return;
}
// set forward direction
char request_str[15];
int16_t yaw_corr = frontend.get_yaw_correction(state.instance);
snprintf(request_str, sizeof(request_str), "#MBF,%d\r\n", (int)yaw_corr);
uart->write(request_str);
// request update on motor direction
uart->write("?MBF\r\n");
_last_request_type = RequestType_ForwardDirection;
_last_request_ms = AP_HAL::millis();
}
// request new data if required
void AP_Proximity_LightWareSF40C::request_new_data()
{
if (uart == nullptr) {
return;
}
// after timeout assume no reply will ever come
uint32_t now = AP_HAL::millis();
if ((_last_request_type != RequestType_None) && ((now - _last_request_ms) > PROXIMITY_SF40C_TIMEOUT_MS)) {
_last_request_type = RequestType_None;
_last_request_ms = 0;
}
// if we are not waiting for a reply, ask for something
if (_last_request_type == RequestType_None) {
_request_count++;
if (_request_count >= 5) {
send_request_for_health();
_request_count = 0;
} else {
// request new distance measurement
send_request_for_distance();
}
_last_request_ms = now;
}
}
// send request for sensor health
void AP_Proximity_LightWareSF40C::send_request_for_health()
{
if (uart == nullptr) {
return;
}
uart->write("?GS\r\n");
_last_request_type = RequestType_Health;
_last_request_ms = AP_HAL::millis();
}
// send request for distance from the next sector
bool AP_Proximity_LightWareSF40C::send_request_for_distance()
{
if (uart == nullptr) {
return false;
}
// increment sector
_last_sector++;
if (_last_sector >= _num_sectors) {
_last_sector = 0;
}
// prepare request
char request_str[15];
snprintf(request_str, sizeof(request_str), "?TS,%d,%d\r\n", (int)(_sector_width_deg[_last_sector]), (int)(_sector_middle_deg[_last_sector]));
uart->write(request_str);
// record request for distance
_last_request_type = RequestType_DistanceMeasurement;
_last_request_ms = AP_HAL::millis();
return true;
}
// check for replies from sensor, returns true if at least one message was processed
bool AP_Proximity_LightWareSF40C::check_for_reply()
{
if (uart == nullptr) {
return false;
}
// read any available lines from the lidar
// if CR (i.e. \r), LF (\n) it means we have received a full packet so send for processing
// lines starting with # are ignored because this is the echo of a set-motor request which has no reply
// lines starting with ? are the echo back of our distance request followed by the sensed distance
// distance data appears after a <space>
// distance data is comma separated so we put into separate elements (i.e. <space>angle,distance)
uint16_t count = 0;
int16_t nbytes = uart->available();
while (nbytes-- > 0) {
char c = uart->read();
// check for end of packet
if (c == '\r' || c == '\n') {
if ((element_len[0] > 0)) {
if (process_reply()) {
count++;
}
}
// clear buffers after processing
clear_buffers();
ignore_reply = false;
wait_for_space = false;
// if message starts with # ignore it
} else if (c == '#' || ignore_reply) {
ignore_reply = true;
// if waiting for <space>
} else if (c == '?') {
wait_for_space = true;
} else if (wait_for_space) {
if (c == ' ') {
wait_for_space = false;
}
// if comma, move onto filling in 2nd element
} else if (c == ',') {
if ((element_num == 0) && (element_len[0] > 0)) {
element_num++;
} else {
// don't support 3rd element so clear buffers
clear_buffers();
ignore_reply = true;
}
// if part of a number, add to element buffer
} else if (isdigit(c) || c == '.' || c == '-') {
element_buf[element_num][element_len[element_num]] = c;
element_len[element_num]++;
if (element_len[element_num] >= sizeof(element_buf[element_num])-1) {
// too long, discard the line
clear_buffers();
ignore_reply = true;
}
}
}
return (count > 0);
}
// process reply
bool AP_Proximity_LightWareSF40C::process_reply()
{
if (uart == nullptr) {
return false;
}
bool success = false;
switch (_last_request_type) {
case RequestType_None:
break;
case RequestType_Health:
// expect result in the form "0xhhhh"
if (element_len[0] > 0) {
int result;
if (sscanf(element_buf[0], "%x", &result) > 0) {
_sensor_status.value = result;
success = true;
}
}
break;
case RequestType_MotorSpeed:
_motor_speed = atoi(element_buf[0]);
success = true;
break;
case RequestType_MotorDirection:
_motor_direction = atoi(element_buf[0]);
success = true;
break;
case RequestType_ForwardDirection:
_forward_direction = atoi(element_buf[0]);
success = true;
break;
case RequestType_DistanceMeasurement:
{
float angle_deg = (float)atof(element_buf[0]);
float distance_m = (float)atof(element_buf[1]);
uint8_t sector;
if (convert_angle_to_sector(angle_deg, sector)) {
_angle[sector] = angle_deg;
_distance[sector] = distance_m;
_distance_valid[sector] = is_positive(distance_m);
_last_distance_received_ms = AP_HAL::millis();
success = true;
// update boundary used for avoidance
update_boundary_for_sector(sector);
}
break;
}
default:
break;
}
// mark request as cleared
if (success) {
_last_request_type = RequestType_None;
}
return success;
}
// clear buffers ahead of processing next message
void AP_Proximity_LightWareSF40C::clear_buffers()
{
element_len[0] = 0;
element_len[1] = 0;
element_num = 0;
memset(element_buf, 0, sizeof(element_buf));
}