Document Type
Post-Print
Publication Date
6-2018
Abstract
In this paper, we develop theoretical foundations for a new class of rehabilitation robot: body powered devices that route power between a user’s joints. By harvesting power from a healthy joint to assist an impaired joint, novel bimanual and self-assist therapies are enabled. This approach complements existing robotic therapies aimed at promoting recovery of motor function after neurological injury.
We employ hydraulic transmissions for routing power, or equivalently for coupling the motions of a user’s joints. Fluid power routed through flexible tubing imposes constraints within a limb or between homologous joints across the body. Variable transmissions allow constraints to be steered on the fly, and simple valve switching realizes free space and locked motion.
We examine two methods for realizing variable hydraulic transmissions: using valves to switch among redundant cylinders (digital hydraulics) or using an intervening electromechanical link. For both methods, we present a rigorous mathematical framework for describing and controlling the resulting constraints. Theoretical developments are supported by experiments using a prototype fluid-power exoskeleton.
Identifier
PMCID: PMC6335049
DOI
10.1109/TRO.2018.2799597
Publisher
IEEE
Repository Citation
Treadway, E., Gan, Z., Remy, C. D., & Gillespie, R. B. (2018). Toward controllable hydraulic coupling of joints in a wearable robot. IEEE Transactions on Robotics, 34(3), 748-763. doi: 10.1109/TRO.2018.2799597
Publication Information
IEEE Transactions on Robotics