A robot test-bed for assistance and assessment in physical therapy

This article describes an experimental test-bed that was developed to assist and assess rehabilitation during physical and occupational therapy. A PUMA 260 robot was used for which a controller and interface software was developed in-house. The robot can operate in two modes: (i) passive and (ii) active. In the passive mode, the robot moves the subject’s arm through specified paths. In the active mode, a subject guides the robot along a predefined path overcoming a specified joint stiffness matrix. In this mode, the controller provides gravity compensation so that the robot can support its own weight in an arbitrary configuration. The developed graphical interface enables display of the current configuration of the robot in real-time, customize experiments to a specific subject, and collect force and position data during an experiment. The results of a preliminary study using this test-bed are also presented along with issues involved in choice of paths and interpretation of the results.