You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
61 lines
2.7 KiB
61 lines
2.7 KiB
/* |
|
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_WindVane_ModernDevice.h" |
|
// read wind speed from Modern Device rev p wind sensor |
|
// https://moderndevice.com/news/calibrating-rev-p-wind-sensor-new-regression/ |
|
|
|
// constructor |
|
AP_WindVane_ModernDevice::AP_WindVane_ModernDevice(AP_WindVane &frontend) : |
|
AP_WindVane_Backend(frontend) |
|
{ |
|
_speed_analog_source = hal.analogin->channel(ANALOG_INPUT_NONE); |
|
_temp_analog_source = hal.analogin->channel(ANALOG_INPUT_NONE); |
|
} |
|
|
|
void AP_WindVane_ModernDevice::update_speed() |
|
{ |
|
float analog_voltage = 0.0f; |
|
|
|
// only read temp pin if defined, sensor will do OK assuming constant temp |
|
float temp_ambient = 28.0f; // equations were generated at this temp in above data sheet |
|
if (is_positive(_frontend._speed_sensor_temp_pin.get())) { |
|
_temp_analog_source->set_pin(_frontend._speed_sensor_temp_pin.get()); |
|
analog_voltage = _temp_analog_source->voltage_average(); |
|
temp_ambient = (analog_voltage - 0.4f) / 0.0195f; // deg C |
|
// constrain to reasonable range to avoid deviating from calibration too much and potential divide by zero |
|
temp_ambient = constrain_float(temp_ambient, 10.0f, 40.0f); |
|
} |
|
|
|
_speed_analog_source->set_pin(_frontend._speed_sensor_speed_pin.get()); |
|
_current_analog_voltage = _speed_analog_source->voltage_average(); |
|
|
|
// apply voltage offset and make sure not negative |
|
// by default the voltage offset is the number provide by the manufacturer |
|
analog_voltage = _current_analog_voltage - _frontend._speed_sensor_voltage_offset; |
|
if (is_negative(analog_voltage)) { |
|
analog_voltage = 0.0f; |
|
} |
|
|
|
// simplified equation from data sheet, converted from mph to m/s |
|
_frontend._speed_apparent_raw = 24.254896f * powf((analog_voltage / powf(temp_ambient, 0.115157f)), 3.009364f); |
|
} |
|
|
|
void AP_WindVane_ModernDevice::calibrate() |
|
{ |
|
gcs().send_text(MAV_SEVERITY_INFO, "WindVane: rev P. zero wind voltage offset set to %.1f",double(_current_analog_voltage)); |
|
_frontend._speed_sensor_voltage_offset.set_and_save(_current_analog_voltage); |
|
_frontend._calibration.set_and_save(0); |
|
}
|
|
|