Development ofaHandMotionAssist RobotforRehabilitation TherapybyPatient Self-Motion Control

Thispaperpresents a newhandmotionassist robotforrehabilitation therapy. Therobotisanexoskeleton with18DOFs anda self-motion control, whichallows the impaired handofapatient tobedriven byhisorherhealthy handontheopposite side. Toprovide suchpotential thatthe impaired handisabletorecover itsability tothelevel ofa functional hand,thehandmotionassist robotisdesigned to support theflexion/extension andabduction/adduction motions offingers andthumbindependently aswellastheopposability ofthethumb.Moreover, itisdesigned tosupport acombination motion ofthehandandthewrist. Thedesign specifications and experimental results areshown. I.INTRODUCTION T henumber ofpatients with adisability inacertain part of lthebodyasaresult ofacerebral vascular accident (CVA)orbonefracture isincreasing instep withtheaging of thepopulation inJapan. Thesepatients needtimely and persistent rehabilitation torecover their lost abilities and regain their normal daily lives. Longrehabilitation training sessions withtherapists, whoareinrelative shortage, arenot always possible forpatients toobtain. A solution tothis problem wouldbearehabilitation system thatallows the patient tocarry outrehabilitation exercises byhimorherself. Many systems forrehabilitation havebeenstudied. Functional electrical stimulation (FES) (1), (2)hasproven to beavaluable tool intherestoration ofarmfunction topatients, butthis approach isnotsuitable forpatient self-controlled rehabilitation therapy. Many aspects of robotic arm rehabilitation therapy (3)-(5), including clinical tests (6), (7), havebeenreported. Mostdisabilities caused byCVAsare