Abstract: A drive assembly for an exercise device is provided. The drive assembly is made up of a base with side supports and an electric motor drive mechanism. The electric motor drive mechanism is an electric motor with a worm gear attached to two driving pulleys via one way clutches. The drive mechanism is supported with outboard bearing mounts located in the side supports. A torque arm and spring assembly restricts rotation of the mechanism, but allows limited rotational movement. This limited movement attenuates shock torsional loads and as a result reduces the structural and electrical size requirements for the overall device.

Abstract: A simulated stair climbing exercise apparatus having variable sensory feedback is provided. Sensory feedback, in the form of a lifting force acting on a lifting foot of the operator, varies with the operator's location in the stepping stroke. Maximum sensory feedback is provided at a lower portion of the stroke, minimum sensory feedback is provided at an upper portion of the stroke and maximum feedback at the lower portions. Sensory feedback is effected by means of direct interconnection of left and right foot mechanisms in combination with a spring. Direct interconnection is achieved by a cable routed around a series of pulleys such that a downward force on one foot mechanism results in an equal and opposite lifting force on the other foot mechanism. One of the pulleys is a floating pulley that is free to move and its positioned based upon the operating position of the stepping stroke.