Robot-Aided Wrist Rehabilitation After Stroke
The goal of this research is to extend robotic therapy to wrist rotations using a novel, 3-degree-of-freedom robotic therapy device for the wrist. This robot is capable of tracking, guiding, and perturbing a person’s wrist rotations while he/she performs a set of virtual tasks. The first stage of this project consists of establishing a quantitative [...]
Performance-Based Progressive Therapy (PBPT) Enhances Neural Plasticity
An initial therapy protocol for 42 chronic stroke patients (≥ 3 months post-stroke) consisted of robot-assisted moves to and from 8 targets that are oriented like a compass, starting with the north target and proceeding clockwise, i.e., N, NE, E, SE, etc. This therapy resulted in statistically significant reductions in shoulder and elbow impairment and [...]
MRI Compatible Wrist Robot
The MIT Wrist Robot, designed by Dustin Williams, [1] has demonstrated the effectiveness of robotic therapy in aiding the rehabilitation of stroke victims. In an effort to better understand the neurological processes involved in this therapy and evaluate its effectiveness a patented MRI compatible version of the wrist robot is under development so that therapy [...]
Semi-active variable-impedance materials
In collaboration with team 4.3 at the Institute for Soldier Nanotechnologies, and under the combined guidance of Drs. Neville Hogan and Gareth McKinley, this project is devoted to the study of semi-active variable-impedance materials in the context of enhancing human biomechanical performance. The challenge of this project is to develop biomechanically sound devices with semi-active [...]
Movement primitives and human arm movements
Velocity profiles of voluntary unconstrained human arm movements under some conditions, e.g., during accurate movements, are irregular. Specifically, the velocity profiles of the hand paths (Vt) exhibit fluctuations from the typical bell-shaped profile. What is the nature of such fluctuations? Do these fluctuations reveal anything about the nature of the controller of human arm movements? [...]
Improving Force-Based Interaction Control Using Limited Knowledge of Environment Dynamics
Robots for neurological rehabilitation require actuators with high force/weight ratio and low mechanical impedance. Conventional actuators with high force capacity are generally either extremely heavy (e.g. electromagnetic actuators) or have high endpoint impedance (e.g. geared actuators). Measurement of the endpoint force can be used with feedback control to reduce the apparent impedance, but this can seriously compromise [...]
Finding Objective Function and Mathematical Model of Locomotion of Normal/Impaired Subjects
Despite of redundancy in locomotion, generally, we follow common pattern while walking or running. Therefore, we can infer or at least assume that there is an objective function that our CNS solve while locomotion. My goal is to find proper objective function by considering known behaviors. In parallel, I expect to suggest or modify a [...]
Brain Stimulation and Motor Control
Publications: Levy-Tzedek, S., Arle, J.E., Apetauerova, D., Shils, J.L., Gould, C., Krebs, H.I. (2006) Clinical score improves while motor performance deteriorates in a parkinsonian patient with deep-brain stimulation. 2006 ACRM-ASNR Joint Conference (accepted). Apetauerova, D., Levy-Tzedek, S., Gould, C., Arle, J.E., Shils, J.L., Penney, D., Krebs, H.I. (2006) Impaired visual perception in a patient with [...]
The Effect of Proximal and Distal Training on Stroke Recovery
How can motor recovery following a stroke be maximized? Is “optimal therapy” bound to an all encompassing functional training or is a modular training approach, involving specificity and proper sequence of training to each limb segment, also effective? This project has the following specific aims: 1) Test whether specific wrist robotic training improves motor performance [...]
Hydraulic Transmissions for “High Force Haptic” Device Actuation
Robots for neurological rehabilitation and similar “high force haptic” devices require actuators with high force/weight ratio and the ability to render virtual objects, which requires low mechanical impedance. Conventional actuators are generally inadequate when the device kinematics are complicated. In this actuator development project, a low-impedance electromagnetic source actuator is used with a purely passive hydraulic transmission [...]
Robot-Aided Grasp Rehabilitation
This research is focused on Biomechanics and Robotic Rehabilitation Technologies; the main investigations are the dynamic and kinematic studies of mechanisms and actuators, and the engineering of chain measurements. Now under development is a modular device for rehabilitation of the hand, which can be used with stroke patients.
Spectral Estimation of Mechanical Impedance of Hemiplegic Arms
Patients with stroke who had robotic therapy using a performance-based, progressive protocol experienced a marked change in tone – a muscle’s resistance to passive elongation or stretch [1,2]. Although clinicians judge muscle tone subjectively, an objective measure would provide valuable insight about the effect of stroke on a hemiplegic limb and better characterize the effect [...]
Spinal Rat Rehabilitation Robot
The initial goal of this research is to develop a platform that researchers can use to examine how rats relearn how to walk after a spinal cord injury. Previous devices were attached to treadmills. The novelty of this device is that it is mobile to allow recovery in a relatively unstructured environment. With this type [...]
