Sensors Used for Autonomous Navigation

Abstract

Navigation and guidance are defined as the processes of determining and controlling the position of a vehicle. An autonomous system will have to include these two basic procedures to perform any useful task. The information generally required for navigation is the direction, speed, and position of the vehicle. The basic navigation techniques were designed several years ago to navigate vessels across the ocean. In the past the position of ships was estimated with dead reckoning techniques using speed and heading observations. With this information the trajectory of the ship was predicted with errors that accumulated over time. The heading information was obtained with the position of the sun or other stars and the velocity was evaluated with a log compensating for the effect of local currents. Absolute information was also used to correct the position estimation. These fixes were done when well-known natural landmarks were recognised. The Mediterranean was the testing place of all these techniques. It was appropriate since the water currents are light in most places and many natural landmarks can be seen along most possible journeys.