Landing strategies in honeybees, and possible applications to autonomous airborne vehicles

Insects, being perhaps more reliant on image motion cues than mammals or hi gher vertebrates, are proving to be an excellent organism in which to inves tigate how information on optic flow is exploited to guide locomotion and n avigation. This paper describes one example, illustrating how bees perform grazing landings on a flat surface. A smooth landing is achieved by a surpr isingly simple and elegant strategy: image velocity is held constant as the surface is approached, thus automatically ensuring that flight speed is cl ose to zero at touchdown. No explicit knowledge of flight speed or height a bove the ground is necessary. The feasibility of this landing strategy is t ested by implementation in a robotic gantry, and its applicability to auton omous airborne vehicles is discussed.