For children, the urge to move is a basic need. Movement is essential for the development of physical and mental abilities. Quite often, for children with intellectual and physical disabilities who require special supportive seating, other considerations receive priority over movement in seats. The result is an even greater reduction of their…

We describe an algorithm based on motion-planning techniques to determine the existence of an accessible route through a facility for a wheeled mobility device. The algorithm is based on LaValle's work on rapidly exploring random trees and is enhanced to take into consideration the particularities of the accessible route domain. Specifically, the…

Many experimenters, starting with Ernst Mach in 1883, have reported that if a device alternately sucks in and then expels a surrounding fluid, it moves in the same direction as if it only expelled fluid. This surprising phenomenon, which we call "Machian propulsion", is explained by conservation of momentum: the outflow efficiently transfers…