Rehabilitation and Health Care Robotics 53.2 Physical Therapy and Training Robots 1231 in different directions and assist in reaching in a straight cylinders to help extend or flex the fingers,and has been line.Chronic stroke patients who received assistance shown to improve hand movement ability of chronic during reaching with the robot improved their move- stroke subjects [53.50].Simple force-feedback con- ment ability [53.44].However,they improved about as trolled devices,including a one-DOF wrist manipulator much as a control group that simply practised a matched and a two-DOF elbow-shoulder manipulator,were also number of reaches without assistance from the robot. recently shown to improve movement ability of chronic This suggests that movement effort by the patient is stroke subjects who exercised with the devices [53.51]. a key factor for recovery,although the small sample size A passive exoskeleton,the T-WREX arm orthosis,pro- of this study limited its ability to resolve the size of the vides support to the arm against gravity using elastic difference between guided and unguided therapy. bands,while still allowing a large range of motion of the arm [53.52].By incorporating a simple hand-grasp Bi-Manu-Track sensor,this device allows substantially weakened pa- Perhaps the most striking clinical results generated so tients to practise simple virtual reality exercises that far have come from one of the simplest devices built.simulate functional tasks such as shopping and cooking. Similar to a design proposed previously [53.45],the Chronic stroke patients who practised exercising with Bi-Manu-Track uses two motors,one for each hand,to this non-robotic device recovered significant amounts allow bimanual wrist-flexion extension [53.46].The de-of movement ability,comparable with the Fugl-Meyer vice can also assist in forearm pronation/supination if it gains seen with MIT-MANUS and MIME.NeReBot is tilted downward and the handles are changed.In an is a three-DOF wire-based robot that can slowly move extensive clinical test of the device,22 subacute patients a stroke patient's arm in spatial paths.Acute stroke (i.e.,4-6 weeks after stroke)practised 800 movements patients who received additional movement therapy art with the device for 20 min per day,five days per week beyond their conventional rehabilitation therapy with for six weeks [53.461.For half of the movements,the de-NeReBot recovered significantly more movement ability vice drove both arms,and for the other half,the patient's than patients who received just conventional rehabilita- stronger arm drove the motion of the more-impaired arm.tion therapy [53.53].RehaRob uses an industrial robot A control group received a matched duration of electri- arm to mobilize patients'arms along arbitrary trajecto- cal stimulation(ES)of their wrist extensor muscles,with ries following stroke [53.54]. the stimulation triggered by voluntary activation of their muscles when possible,as measured by electromyo- Other Systems Currently under Development graphy (EMG).The number of movements performed Several other robotic therapy devices are currently under with EMG-triggered ES was 60-80 per session.The development.For example,at the high end of cost and robot-trained group improved by 15 points more on the complexity are the ARM-In [53.55]and Pneu-WREX Fugl-Meyer scale,a standard clinical scale of movement systems [53.56],which are exoskeletons that accommo- ability with a range from 0 to 66 points in upper extrem- date nearly naturalistic movement of the arm while still ity function.It assigns a score of 0(cannot complete),I achieving a wide range of force control.A system that (completes partially),or 2(completes normally)for 33 couples a immersive virtual-reality display with a haptic test movements,such as lifting the arm without flexing robot arm is described in [53.571.A wearable exoskele- the elbow.For comparison,reported gains in Fugl-Meyer ton driven by pneumatic muscles is described in [53.58]. score after therapy with the MIT-MANUS and MIME At the lower end of cost/complexity are devices that use devices ranged from 0-5 points [53.47]. force feedback joysticks and steering wheels with a view toward implementation in the home [53.59-62].Exam- Other Devices to Undergo Clinical Testing ples of recent,novel robotic devices for the hand are Other devices to undergo clinical testing are as fol-given in [53.63-65]:these devices typically follow an lows.The GENTLE/s system uses a commercial robot,active assist therapy paradigm in that they are designed the HapticMaster,to assist in patient movement as the to help open and close the hand.One robotic therapy patient plays video games.The HapticMaster allows system for the hand incorporates the idea of using visual four degrees of freedom of movement and achieves feedback distortion to enhance motivation of patients a high bandwidth of force control using force feedback. during movement therapy [53.66].Using robotic force Chronic stroke patients who exercised with GENTLE/s fields to amplify the kinematic errors of stroke patients improved their movement ability [53.48,49].The Rut- during reaching may provoke novel forms of adaptation gers hand robotic device uses low-friction pneumatic of those patterns [53.4,67].Rehabilitation and Health Care Robotics 53.2 Physical Therapy and Training Robots 1231 in different directions and assist in reaching in a straight line. Chronic stroke patients who received assistance during reaching with the robot improved their move￾ment ability [53.44]. However, they improved about as much as a control group that simply practised a matched number of reaches without assistance from the robot. This suggests that movement effort by the patient is a key factor for recovery, although the small sample size of this study limited its ability to resolve the size of the difference between guided and unguided therapy. Bi-Manu-Track Perhaps the most striking clinical results generated so far have come from one of the simplest devices built. Similar to a design proposed previously [53.45], the Bi-Manu-Track uses two motors, one for each hand, to allow bimanual wrist-flexion extension [53.46]. The de￾vice can also assist in forearm pronation/supination if it is tilted downward and the handles are changed. In an extensive clinical test of the device, 22 subacute patients (i. e., 4–6 weeks after stroke) practised 800 movements with the device for 20 min per day, five days per week for six weeks [53.46]. For half of the movements, the de￾vice drove both arms, and for the other half, the patient’s stronger arm drove the motion of the more-impaired arm. A control group received a matched duration of electri￾cal stimulation (ES) of their wrist extensor muscles, with the stimulation triggered by voluntary activation of their muscles when possible, as measured by electromyo￾graphy (EMG). The number of movements performed with EMG-triggered ES was 60–80 per session. The robot-trained group improved by 15 points more on the Fugl-Meyer scale, a standard clinical scale of movement ability with a range from 0 to 66 points in upper extrem￾ity function. It assigns a score of 0 (cannot complete), 1 (completes partially), or 2 (completes normally) for 33 test movements, such as lifting the arm without flexing the elbow. For comparison, reported gains in Fugl-Meyer score after therapy with the MIT-MANUS and MIME devices ranged from 0–5 points [53.47]. Other Devices to Undergo Clinical Testing Other devices to undergo clinical testing are as fol￾lows. The GENTLE/s system uses a commercial robot, the HapticMaster, to assist in patient movement as the patient plays video games. The HapticMaster allows four degrees of freedom of movement and achieves a high bandwidth of force control using force feedback. Chronic stroke patients who exercised with GENTLE/s improved their movement ability [53.48, 49]. The Rut￾gers hand robotic device uses low-friction pneumatic cylinders to help extend or flex the fingers, and has been shown to improve hand movement ability of chronic stroke subjects [53.50]. Simple force-feedback con￾trolled devices, including a one-DOF wrist manipulator and a two-DOF elbow–shoulder manipulator, were also recently shown to improve movement ability of chronic stroke subjects who exercised with the devices [53.51]. A passive exoskeleton, the T-WREX arm orthosis, pro￾vides support to the arm against gravity using elastic bands, while still allowing a large range of motion of the arm [53.52]. By incorporating a simple hand-grasp sensor, this device allows substantially weakened pa￾tients to practise simple virtual reality exercises that simulate functional tasks such as shopping and cooking. Chronic stroke patients who practised exercising with this non-robotic device recovered significant amounts of movement ability, comparable with the Fugl-Meyer gains seen with MIT-MANUS and MIME. NeReBot is a three-DOF wire-based robot that can slowly move a stroke patient’s arm in spatial paths. Acute stroke patients who received additional movement therapy beyond their conventional rehabilitation therapy with NeReBot recovered significantly more movement ability than patients who received just conventional rehabilita￾tion therapy [53.53]. RehaRob uses an industrial robot arm to mobilize patients’ arms along arbitrary trajecto￾ries following stroke [53.54]. Other Systems Currently under Development Several other robotic therapy devices are currently under development. For example, at the high end of cost and complexity are the ARM-In [53.55] and Pneu-WREX systems [53.56], which are exoskeletons that accommo￾date nearly naturalistic movement of the arm while still achieving a wide range of force control. A system that couples a immersive virtual-reality display with a haptic robot arm is described in [53.57]. A wearable exoskele￾ton driven by pneumatic muscles is described in [53.58]. At the lower end of cost/complexity are devices that use force feedback joysticks and steering wheels with a view toward implementation in the home [53.59–62]. Exam￾ples of recent, novel robotic devices for the hand are given in [53.63–65]: these devices typically follow an active assist therapy paradigm in that they are designed to help open and close the hand. One robotic therapy system for the hand incorporates the idea of using visual feedback distortion to enhance motivation of patients during movement therapy [53.66]. Using robotic force fields to amplify the kinematic errors of stroke patients during reaching may provoke novel forms of adaptation of those patterns [53.4, 67]. Part F 53.2