A robot is helping stroke victims regain movement in their arms. The robot was created by Jules Dewald, PhD, associate professor of physical therapy and human movement sciences, physical medicine, and rehabilitation and biomedical engineering at Northwestern University, Chicago, IL, and Wim Lam, owner and general manager of Lam Design Management of Orchard Park, NY.

Most people who have suffered a stroke find reaching out very difficult to do unless the arm is fully supported. Up to now an air bearing device that slides over a large table has been used, but this is a clumsy solution. Lam's company represented a robot called the HapticMASTER from Netherlands-based Moog FCS B.V., and Lam suggested that perhaps the robot could replace a real table with a virtual one for the benefit of stroke victims. The idea was to create a virtual world for stroke victims, so that the weight of their arm could be fully eliminated and then gradually reintroduced.

A chair created by Biodex Medical Devices,Shirley, NY, provides an adjustable seat that allows individuals to be placed in the correct position with respect to the robot. The combination of the Biodex chair and the HapticMASTER robot created the new ACT3D system.The built-in interface, which supports the hand and forearm, is connected to a gimble, which is attached to a special load cell.

The computer creates a virtual world with objects and responds to a patient's movements. The robot processes 3-D information, allowing subjects to see their arm and the virtual objects in space.It generates a sensation of contact with physical objects. The video interface Feedback provides a realistic feel to the objects in the virtual environment. Over time, the robot can be set to to allow the patient to control more and more of the weight of his arm, until he can deal with the real weight of the arm as he explores the work space.

The next iteration of the ACT3D, a system help patients regain hand/finger dexterity, is already in progress.