Robot-Aided Training of Propulsion: Effects of Torque Pulses Applied to the Hip and Knee Joint Under User-Driven Treadmill Control.

Objective: to establish whether torque pulses ap-plied by an exoskeleton to the hip and knee joint modulate propulsion mechanics and whether changes in propulsion me-chanics are sustained after exposure to torque pulses under user-driven treadmill control.

Methods: we applied twelve for-mulations of torque pulses consecutively over 300 strides to 22 healthy participants, and quantified the evolution of four outcome measures - gait speed (GS), hip extension (HE), trailing limb angle (TLA), normalized propulsive impulse (NPI) - before, during, and immediately after training.

Results: Metrics of propulsion mechanics significantly changed both during and after training.

Single-stride exposure to pulse torque assistance provided by a robotic exoskeleton at the hip and knee joints.

Robot assisted gait retraining is an increasingly common method for supporting restoration of walking function after neurological injury. Gait speed, an indicator of walking function, is correlated with propulsive force, a measure modulated by the posture of the trailing limb at push-off. With the ultimate goal of improving efficacy of robot assisted gait retraining, we sought to directly target gait propulsion, by exposing subjects to pulses of joint torque applied at the hip and knee joints to modulate push-off posture.

The effect of stride length on lower extremity joint kinetics at various gait speeds.

Robot-assisted training is a promising tool under development for improving walking function based on repetitive goal-oriented task practice. The challenges in developing the controllers for gait training devices that promote desired changes in gait is complicated by the limited understanding of the human response to robotic input. A possible method of controller formulation can be based on the principle of bio-inspiration, where a robot is controlled to apply the change in joint moment applied by human subjects when they achieve a gait feature of interest.

Toward goal-oriented robotic gait training: The effect of gait speed and stride length on lower extremity joint torques.

Robot-assisted gait training is becoming increasingly common to support recovery of walking function after neurological injury. How to formulate controllers capable of promoting desired features in gait, i.e.

Task-Dependent Bimanual Coordination After Stroke: Relationship With Sensorimotor Impairments.

Objectives: To determine (1) bimanual coordination deficits in patients with stroke using 3-dimensional kinematic analyses as they perform naturalistic tasks requiring collaborative interaction of the 2 arms; and (2) whether bimanual coordination deficits are related to clinical measures of sensorimotor impairments and unimanual performance of the paretic arm.

Design: Case-control study.

Setting: Rehabilitation hospital research institute.

Reduced asymmetry in motor skill learning in left-handed compared to right-handed individuals.

Hemispheric specialization for motor control influences how individuals perform and adapt to goal-directed movements. In contrast to adaptation, motor skill learning involves a process wherein one learns to synthesize novel movement capabilities in absence of perturbation such that they are performed with greater accuracy, consistency and efficiency. Here, we investigated manual asymmetry in acquisition and retention of a complex motor skill that requires speed and accuracy for optimal performance in right-handed and left-handed individuals.