In case of aerial vehicle the knowledge of the momentary orientation has primary importance. We need sensor systems which can provide information to surely determine the required intervention with precision and reliability. This kind of sensor system can be formed by so-called inertial sensors, such as the accelerometer, to measure the linear acceleroation and the gyroscope to measure the angular velocity around the axes. Traditionally these sensors are mechanical principled, heavy, difficult and expensive devices, but thanks to the development of the microelectronic industry in the previous one and a half decade, in particular, to the so-called MEMS (MicroElectroMechanical Systems) technology, nowdays these devices are productable at a low price, in chip-scale. It gives opportunity to develop, with many other applications, small size robot aircrafts, so-called unmanned aerial vehicle (UAV).
The subject of this thesis is to introduce the working of the MEMS based inercial sensor systems, to study their usability, to introduce the errors and the effects of the errors, in relation to the UAV applicions. I am going to reveal a 6 degrees of freedom sensor system manufactured by Analog Devices and I am going to show an example of the joint, the signal processing and calculating of the orientation of it in an embedded linux enviroment.
Finally, having accepted the weakness of the inerciol sensors, I am going to mention other sensors for navigation purposes and how we can use them to improve the effeciency of the inercial sensors.