An autonomous vibration-driven device, for motion through a lumen or along a surface, utilizing an array of flexible fibers attached to the body of the device. The outer surface of the fibers have an anisotropic coefficient of friction with the surface along which the device is to move, and the fibers extend from the device body such that at least some of the fibers are in contact with the walls along a part of their length. A transducer is used to vibrate the device, such that it moves down the lumen. The transducer can be either device borne or external. A rotary device is also described, utilizing an array of fibers disposed on the rotor's body, the fibers having an anisotropic coefficient of friction with a central stator or with an outer circular wall. A planar motion device is also described for crawling over a planar surface.