Article

Numerous haptic devices have been developed for upper-limb neurorehabilitation,
but their widespread use has been largely impeded because of complexity and cost.
Here, we describe a variable structure pantograph mechanism combined with a
spring suspension system that produces a versatile rehabilitation robot, called
Universal Haptic Pantograph, for movement training of the shoulder, elbow, and
wrist. The variable structure is a 5-degree-of-freedom (DOF) mechanism composed
of 7 joints, 11 joint axes, and 3 configurable joint locks that reduce the number
of system DOFs to between 0 and 3. The resulting device has eight operational
modes: Arm, Wrist, ISO (isometric) 1, ISO 2, Reach, Lift 1, Lift 2, and Steer.
The combination of available work spaces (reachable areas) shows a high
suitability for movement training of most upper-limb activities of daily living.
The mechanism, driven by series elastic actuators, performs similarly in all
operational modes, with a single control scheme and set of gains. Thus, a single
device with minimal setup changes can be used to treat a variety of upper-limb
impairments that commonly afflict veterans with stroke, traumatic brain injury,
or other direct trauma to the arm. With appropriately selected design parameters,
the developed multimode haptic device significantly reduces the costs of robotic
hardware for full-arm rehabilitation while performing similarly to that of
single-mode haptic devices. We conducted case studies with three patients with
stroke who underwent clinical training using the developed mechanism in Arm,
Wrist, and/or Reach operational modes. We assessed outcomes using Fugl-Meyer
Motor Assessment and Wolf Motor Function Test scores showing that upper-limb
ability improved significantly following training sessions.

Langue : ANGLAIS