/** ****************************************************************************** * @addtogroup OpenPilotModules OpenPilot Modules * @{ * @addtogroup AirspeedModule Airspeed Module * @brief Communicate with airspeed sensors and return values * @{ * * @file baro_airspeed.c * @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010. * @brief Airspeed module, handles temperature and pressure readings from BMP085 * * @see The GNU Public License (GPL) Version 3 * *****************************************************************************/ /* * 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, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /** * Output object: BaroAirspeed * * This module will periodically update the value of the BaroAirspeed object. * */ #include "openpilot.h" #include "hwsettings.h" #include "airspeed.h" #include "airspeedsettings.h" #include "baroairspeed.h" // object that will be updated by the module #if defined(PIOS_INCLUDE_ETASV3) #define SAMPLING_DELAY_MS_ETASV3 50 //Update at 20Hz #define ETS_AIRSPEED_SCALE 1.0f //??? #define CALIBRATION_IDLE_MS 2000 //Time to wait before calibrating, in [ms] #define CALIBRATION_COUNT_MS 2000 //Time to spend calibrating, in [ms] #define ANALOG_BARO_AIRSPEED_TIME_CONSTANT_MS 100.0f //Needs to be settable in a UAVO // Private types // Private variables // Private functions static uint16_t calibrationCount=0; void baro_airspeedGetETASV3(BaroAirspeedData *baroAirspeedData, portTickType *lastSysTime, uint8_t airspeedSensorType, int8_t airspeedADCPin){ static uint32_t calibrationSum = 0; AirspeedSettingsData airspeedSettingsData; AirspeedSettingsGet(&airspeedSettingsData); //Wait until our turn. //THIS SHOULD BE, IF OUR TURN GO IN, OTHERWISE CONTINUE vTaskDelayUntil(lastSysTime, SAMPLING_DELAY_MS_ETASV3 / portTICK_RATE_MS); //Check to see if airspeed sensor is returning baroAirspeedData baroAirspeedData->SensorValue = PIOS_ETASV3_ReadAirspeed(); if (baroAirspeedData->SensorValue==-1) { baroAirspeedData->BaroConnected = BAROAIRSPEED_BAROCONNECTED_FALSE; baroAirspeedData->CalibratedAirspeed = 0; BaroAirspeedSet(&baroAirspeedData); return; } //Calibrate sensor by averaging zero point value //THIS SHOULD NOT BE DONE IF THERE IS AN IN-AIR RESET. HOW TO DETECT THIS? if (calibrationCount < CALIBRATION_IDLE_MS/SAMPLING_DELAY_MS_ETASV3) { calibrationCount++; return; } else if (calibrationCount < (CALIBRATION_IDLE_MS + CALIBRATION_COUNT_MS)/SAMPLING_DELAY_MS_ETASV3) { calibrationCount++; calibrationSum += baroAirspeedData->SensorValue; if (calibrationCount == (CALIBRATION_IDLE_MS + CALIBRATION_COUNT_MS)/SAMPLING_DELAY_MS_ETASV3) { airspeedSettingsData.ZeroPoint = (int16_t) (((float)calibrationSum) / CALIBRATION_COUNT_MS +0.5f); AirspeedSettingsZeroPointSet( &airspeedSettingsData.ZeroPoint ); } else { return; } } //Compute airspeed float calibratedAirspeed = ETS_AIRSPEED_SCALE * sqrtf((float)abs(baroAirspeedData->SensorValue - airspeedSettingsData.ZeroPoint)); //Is this calibrated or indicated airspeed? baroAirspeedData->BaroConnected = BAROAIRSPEED_BAROCONNECTED_TRUE; baroAirspeedData->CalibratedAirspeed = calibratedAirspeed; } #endif /** * @} * @} */