Abstract: A motion device with three legs provides six degrees of freedom using a pair of motor assemblies (22) to drive each leg. Each leg has a differential drive (28, 30, 32, 40) for providing a pitch-roll joint connected to an elbow (16) for providing a pitch joint connected to a second roll joint (56) connected to a universal joint (62, 72). An actuated plate (10) is connected to the universal joint. All of the motors drive the differential drive from the base of the unit and do not add inertia to the actuated plate. The same kinematic arrangement can be used for hand controllers as well as for end effectors and other movable platforms.