GPS Sensor Model

The GPS in Chrono computes the latitude, longitude, and altitude using a spherical coordinate system and GPS reference location that specifies the origin on the simulation. The GPS assumes the Chrono system is Z-Up, X-East, Y-North.

GPS Creation

// create a noise model
auto gps_noise_model=chrono_types::make_shared<ChNoiseNormal>(
    ChVector<float>(1.f, 1.f, 1.f),  // Mean
    ChVector<float>(2.f, 3.f, 1.f)   // Standard Deviation
);
auto gps = chrono_types::make_shared<ChGPSSensor>(
                parent_body,      // body to which the GPS is attached
                gps_update_rate,  // update rate
                gps_offset_pose,  // offset pose from body
                gps_reference,    // reference GPS location (GPS coordinates of simulation origin)
                gps_noise_model   // noise model to use for adding GPS noise
);
 
gps->SetName("GPS");
gps->SetLag(gps_lag);
gps->SetCollectionWindow(gps_collection_time);
 
// GPS data accessfilter
gps->PushFilter(chrono_types::make_shared<ChFilterGPSAccess>());
 
// Addsensorto manager
manager->AddSensor(gps);

GPS data access

utils::CSV_writergps_csv(" ");
UserGPSBufferPtr bufferGPS;
while () {
    bufferGPS=gps->GetMostRecentBuffer<UserGPSBufferPtr>();
    if(bufferGPS->Buffer) {
        // Save the gpsdata to file
        GPSDatagps_data= bufferGPS->Buffer[0];
        gps_csv<<std::fixed <<std::setprecision(6);
        gps_csv<<gps_data.Latitude;   // Latitude
        gps_csv<<gps_data.Longitude;  // Longitude
        gps_csv<<gps_data.Altitude;   // Altitude
        gps_csv<<gps_data.Time;       // Time
        gps_csv<<std::endl;
    }
}
 
gps_csv.write_to_file(gps_file);