Sensors Modeling - PabloRdrRbl/GNC_LAB GitHub Wiki
Introduction
In order to implement an state estimator it is necessary to model the sensor measurements and their errors. In a real aircraft the only way of acquiring the current state of the vehicle is to fuse all the sensor measurements, obtaining an estimation of the state and its confidence.
The desired sensors to be modeled are:
- 3-axis accelerometer
- 3-axis gyro
- 3-axis magnetometer
- Static air sensor (barometric altitude)
- Differential air sensor (indicated airspeed)
- GPS
- Environmental temperature
FlightGear already provides some sensor models for the IMU and GPS, where errors are added to the real state used by the simulator. An alternative approach would be to use the real state and some sensor model in the literature to produce the sensor measurements input to the state estimator.
Extracting sensor data from FlightGear
Sensor data transmission is done using the Generic Protocol.
Additional resources:
- State Vector used by the simulator: (http://jsbsim.sourceforge.net/JSBSim/classJSBSim_1_1FGPropagate.html).
- Space Shuttle Navigation (http://wiki.flightgear.org/Space_Shuttle_Navigation#GP3S).
Inertial Navigation System (INS) / Inertial Measurement Unit (IMU)
Additional resources:
- Adding an INS to an aircraft: (http://wiki.flightgear.org/Inertial_Navigation_System).
- Sensor drift: (https://forum.flightgear.org/viewtopic.php?f=36&t=21889).
Global Navigation Satellite System (GNSS)
Additional resources:
- GPS internals: (http://wiki.flightgear.org/GPS_internals).
Magnetormeter
Additional resources:
- (https://forum.flightgear.org/viewtopic.php?f=66&t=18622).
- (https://sourceforge.net/p/jsbsim/mailman/message/34665681/).
Similar Simulations
Additional resources:
- Using flight gear to test autopilot algorithm: (https://diydrones.com/forum/topics/using-flight-gear-to-test?commentId=705844%3AComment%3A116934).
Paparazzi
Additional resources: