More than 750,000 new or recurrent strokes occur each year in the United States. A large proportion of these Stroke survivors exhibit loss of arm function, which significantly affects thei ability to independently carry out activities of daily living. Recovering lost limb function after stroke requires therapy-often extensive amounts of supervised rehabilitation therapy that starts in the clinic but ideally extends into the home. Robotics offers a promising means to deliver such therapy, but new approaches in human-machine interface, mechanical design, and robot-facilitated interventions are needed. A sufficiently comfortable, lightweight, and portable device is required that facilitates active limb use in everyday tasks and puts the patient in control. Thee are considerable design challenges for a wearable device because motors powerful enough to replace lost muscle function are too heavy to be wearable. In this application, the PIs propose to develop a new class of safe wearable exoskeleton (called eMbots) based on transmissions rather than motors and test its feasibility in restoring arm function in stroke survivors. They see to achieve this overall goal by pursuing the following Specific Aims:
(Aim 1) To design and fabricate an Elbow Wrist OrthotiK with Shoulder drive (EWOKS) hydraulic device and establish its mechanical performance.
(Aim 2) To establish the physiological effects of eMbots on their wearers by performing a series of biomechanical tests. The physiological evaluations will involve both healthy subjects and motor impaired stroke subjects. All human participant experiments will be conducted in parallel with ongoing device development and designs will be continually improved based on experiment results.
(Aim 3) To investigate the efficacy of eMbots to induce recovery of function after stroke by performing a 6-week intervention training in 15 stroke survivors (10 chronic and 5 sub-acute). A series of pre-, post-, and follow-up tests (3 months) of customary clinical measures will be performed to evaluate device efficacy. The proposed application has the potential to transform robotic rehabilitation by providing a new class of wearable robot that may not only benefit stroke survivors, but also individuals suffering from other neurological injuries.

Public Health Relevance

More than two-thirds of the 7 million stroke survivors in the United States live with substantial loss of quality of life because of impaired arm function. Robotic therapy offers a promising approach to restore lost function, but new designs are required to facilitate its use at home. Here, we propose to develop a new class of wearable robotic devices that could improve the quality of life for millions with arm dysfunction.

National Institute of Health (NIH)
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Research Project (R01)
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Special Emphasis Panel (ZEB1-OSR-A (M1))
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Peng, Grace
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University of Michigan Ann Arbor
Engineering (All Types)
Schools of Engineering
Ann Arbor
United States
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