/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*- #include "AP_InertialSensor_Oilpan.h" // ADC channel mappings on for the APM Oilpan // Sensors: GYROX, GYROY, GYROZ, ACCELX, ACCELY, ACCELZ const uint8_t AP_InertialSensor_Oilpan::_sensors[6] = { 1, 2, 0, 4, 5, 6 }; // ADC result sign adjustment for sensors. const int8_t AP_InertialSensor_Oilpan::_sensor_signs[6] = { 1, -1, -1, 1, -1, -1 }; // ADC channel reading the gyro temperature const uint8_t AP_InertialSensor_Oilpan::_gyro_temp_ch = 3; // Maximum possible value returned by an offset-corrected sensor channel const float AP_InertialSensor_Oilpan::_adc_constraint = 900; // ADC : Voltage reference 3.3v / 12bits(4096 steps) => 0.8mV/ADC step // ADXL335 Sensitivity(from datasheet) => 330mV/g, // 0.8mV/ADC step => 330/0.8 = 412 // Tested value : 418 // 1G in the raw data coming from the accelerometer // Value based on actual sample data from 20 boards const float AP_InertialSensor_Oilpan::_gravity = 423.8; ///< would like to use _gravity here, but cannot //const float AP_InertialSensor_Oilpan::_accel_x_scale = 9.80665 / 413.195; //const float AP_InertialSensor_Oilpan::_accel_y_scale = 9.80665 / 412.985; //const float AP_InertialSensor_Oilpan::_accel_z_scale = 9.80665 / 403.69; #define ToRad(x) (x*0.01745329252) // *pi/180 // IDG500 Sensitivity (from datasheet) => 2.0mV/degree/s, // 0.8mV/ADC step => 0.8/3.33 = 0.4 // Tested values : 0.4026, ?, 0.4192 const float AP_InertialSensor_Oilpan::_gyro_gain_x = ToRad(0.4); const float AP_InertialSensor_Oilpan::_gyro_gain_y = ToRad(0.41); const float AP_InertialSensor_Oilpan::_gyro_gain_z = ToRad(0.41); const AP_Param::GroupInfo AP_InertialSensor_Oilpan::var_info[] PROGMEM = { // index 0 was used for the old orientation matrix AP_GROUPINFO("XH", 0, AP_InertialSensor_Oilpan, _x_high, 2465), AP_GROUPINFO("XL", 1, AP_InertialSensor_Oilpan, _x_low, 1617), AP_GROUPINFO("YH", 2, AP_InertialSensor_Oilpan, _y_high, 2465), AP_GROUPINFO("YL", 3, AP_InertialSensor_Oilpan, _y_low, 1617), AP_GROUPINFO("ZH", 4, AP_InertialSensor_Oilpan, _z_high, 2465), AP_GROUPINFO("ZL", 5, AP_InertialSensor_Oilpan, _z_low, 1617), AP_GROUPEND }; /* ------ Public functions -------------------------------------------*/ AP_InertialSensor_Oilpan::AP_InertialSensor_Oilpan( AP_ADC * adc ) : _adc(adc) { _gyro.x = 0; _gyro.y = 0; _gyro.z = 0; _accel.x = 0; _accel.y = 0; _accel.z = 0; } uint16_t AP_InertialSensor_Oilpan::init( AP_PeriodicProcess * scheduler) { _adc->Init(scheduler); _accel_mid.x = (_x_high + _x_low) / 2; _accel_mid.y = (_y_high + _y_low) / 2; _accel_mid.z = (_z_high + _z_low) / 2; _accel_scale.x = 9.80665 / ((float)_x_high - _accel_mid.x); _accel_scale.y = 9.80665 / ((float)_y_high - _accel_mid.y); _accel_scale.z = 9.80665 / ((float)_z_high - _accel_mid.z); #if defined(DESKTOP_BUILD) return AP_PRODUCT_ID_SITL; #elif defined(__AVR_ATmega1280__) return AP_PRODUCT_ID_APM1_1280; #else return AP_PRODUCT_ID_APM1_2560; #endif } bool AP_InertialSensor_Oilpan::update() { float adc_values[6]; _sample_time = _adc->Ch6(_sensors, adc_values); _temp = _adc->Ch(_gyro_temp_ch); _gyro.x = _gyro_gain_x * _sensor_signs[0] * _gyro_apply_std_offset( adc_values[0] ); _gyro.y = _gyro_gain_y * _sensor_signs[1] * _gyro_apply_std_offset( adc_values[1] ); _gyro.z = _gyro_gain_z * _sensor_signs[2] * _gyro_apply_std_offset( adc_values[2] ); // _accel.x = _accel_x_scale * _sensor_signs[3] * _accel_apply_std_offset( adc_values[3] ); // _accel.y = _accel_y_scale * _sensor_signs[4] * _accel_apply_std_offset( adc_values[4] ); // _accel.z = _accel_z_scale * _sensor_signs[5] * _accel_apply_std_offset( adc_values[5] ); _accel.x = _accel_scale.x * _sensor_signs[3] * (adc_values[3] - _accel_mid.x); _accel.y = _accel_scale.y * _sensor_signs[4] * (adc_values[4] - _accel_mid.y); _accel.z = _accel_scale.z * _sensor_signs[5] * (adc_values[5] - _accel_mid.z); /* * X = 1619.30 to 2445.69 * Y = 1609.45 to 2435.42 * Z = 1627.44 to 2434.82 */ return true; } bool AP_InertialSensor_Oilpan::new_data_available( void ) { return _adc->new_data_available(_sensors); } float AP_InertialSensor_Oilpan::gx() { return _gyro.x; } float AP_InertialSensor_Oilpan::gy() { return _gyro.y; } float AP_InertialSensor_Oilpan::gz() { return _gyro.z; } void AP_InertialSensor_Oilpan::get_gyros( float * g ) { g[0] = _gyro.x; g[1] = _gyro.y; g[2] = _gyro.z; } float AP_InertialSensor_Oilpan::ax() { return _accel.x; } float AP_InertialSensor_Oilpan::ay() { return _accel.y; } float AP_InertialSensor_Oilpan::az() { return _accel.z; } void AP_InertialSensor_Oilpan::get_accels( float * a ) { a[0] = _accel.x; a[1] = _accel.y; a[2] = _accel.z; } void AP_InertialSensor_Oilpan::get_sensors( float * sensors ) { sensors[0] = _gyro.x; sensors[1] = _gyro.y; sensors[2] = _gyro.z; sensors[3] = _accel.x; sensors[4] = _accel.y; sensors[5] = _accel.z; } float AP_InertialSensor_Oilpan::temperature() { return _temp; } uint32_t AP_InertialSensor_Oilpan::sample_time() { return _sample_time; } void AP_InertialSensor_Oilpan::reset_sample_time() { } /* ------ Private functions -------------------------------------------*/ float AP_InertialSensor_Oilpan::_gyro_apply_std_offset( float adc_value ) { /* Magic number from AP_ADC_Oilpan.h */ return ((float) adc_value ) - 1658.0f; } float AP_InertialSensor_Oilpan::_accel_apply_std_offset( float adc_value ) { /* Magic number from AP_ADC_Oilpan.h */ return ((float) adc_value ) - 2041.0f; } // return the oilpan gyro drift rate in radian/s/s float AP_InertialSensor_Oilpan::get_gyro_drift_rate(void) { // 3.0 degrees/second/minute return ToRad(3.0/60); }