Conference Paper

Collision Recognition and Direction Changes Using Fuzzy Logic for Small Scale Fish Robots by Acceleration Sensor Data.

DOI: 10.1007/11540007_41 Conference: Fuzzy Systems and Knowledge Discovery, Second International Conference, FSKD 2005, Changsha, China, August 27-29, 2005, Proceedings, Part II
Source: DBLP

ABSTRACT For natural and smooth movement of small scale fish robots, collision detection and direction changes are important. Typical
obstacles are walls, rocks, water plants and other nearby robots for a group of small scale fish robots and submersibles that
have been constructed in our lab. Two of 2-axes acceleration sensors are employed to measure the three components of collision
angles, collision magnitudes, and the angles of robot propulsion. These data are integrated using fuzzy logic to calculate
the amount of propulsion direction changes. Because caudal fin provides the main propulsion for a fish robot, there is a periodic
swinging noise at the head of a robot. This noise provides a random acceleration effect on the measured acceleration data
at the collision instant. We propose an algorithm based on fuzzy logic which shows that the MEMS-type accelerometers are very
effective to provide information for direction changes.

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