Pr oc. 5 th Intl Conf. Disability, Virtual Reality & Assoc. Tech., Ox ford, UK, 2004 2004 ICDVRAT/University of Reading, UK; ISBN 07 049 11 44 2 3 3 Robot aided therapy: challenges ahead for upper limb stroke rehabilitation R C V Loureiro, C F Collin and W S Harwin Department of Cybernetics, The University of Reading, Whiteknights, Reading, RG6 6AY, UK r.c.v.loureiro@reading.ac.uk, Christine.Collin@rbbh-tr.anglox.nhs.uk, w.s.harwin@reading.ac.uk www.isrg.reading.ac.uk ABSTRACT People who have been discharged from hospital following a stroke still have a potential to continue their recovery by doing therapy at home. Unfortunately it is difficult to exercise a stroke affected arm correctly and many people simply resort to using their good arm for most activities. This strategy makes many tasks difficult and any tasks requiring two hands become nearly impossible. The use of haptic interface technologies will allow the reach and grasp movements to be retrained by either assisting movement, or directing movement towards a specified target. This paper demonstrates how initial work on machine mediated therapies can be made available to a person recovering at home. 1. INTRODUCTION Stroke is a leading cause of disability in the UK, with incidence rates between 1.25 and 1.8 per 1000 people per annum with the rate higher in Scotland and higher for men (Stewart et al, 1999; Scottish Health Statistics, 2002). Traditional treatments rely on the use of physiotherapy that is partially based on theories and also heavily reliant on the therapists training and past experience. The lack of evidence to prove that one treatment is more effective than any other makes the rehabilitation of stroke patients a difficult task. Upper limb motor re-learning and recovery levels improve with intensive physiotherapy. The need for conclusive evidence supporting one method over the other and the need to stimulate the stroke patient clearly suggest that traditional methods lack high motivational content, as well as objective standardised analytical methods for evaluating a patient’s performance and assessment of therapy effectiveness. Although the causes of stroke are well known and it is possible to reduce these risks, there is still a need to improve rehabilitation techniques. 2. CURRENT STATE-OF-THE-ART 2.1 Early interventions According to physiotherapy literature, attention and motivation are key factors for motor relearning following stroke (Yekutiel, 2000). One way to achieve early intensive interventions is via machine mediated therapies but there is a lack of good tools available to the therapist. Several authors have already proposed the use of robotics for the delivery of this type of physiotherapy. The first far-reaching study on acceptance of robot technology in occupational therapy for both patients and therapists was done by Dijkers and colleagues using a simple therapy robot (Dijkers et al, 1991). Dijkers study reports a wide acceptance from both groups, together with a large number of valuable suggestions for improvements. Advantages of Dijkers therapy include the availability of the robot to successively repeat movements without grievance, as well as, the ability to record movements. However, there was no measure of movement quality and patient cooperation was not monitored. 2.2 Recent research More recent studies however, follow a more task oriented approach. Johnson et al, (1999) have developed the SEAT: “simulation environment for arm therapy” to test the principle of the ‘mirrored-image’ by the provision of bimanual, patient controlled therapeutic exercise. The device comprises of a customised design