Development of Digital Control for Machines Designed to Evaluate/Rehabilitate Muscular Deficits

Development of digital feedback control is addressed for a series of machines, manufactured by Isotechnologies, Inc. for use by therapists in evaluating and rehabilitating musculoskeletal problems and injuries. These machines, called Isostations, allow movement in three dimensions against graded, controllable resistance generated by forcing fluid through hydraulic servo valves. Design considerations are presented, problem areas are identified, and preliminary valve control simulations are discussed.