Robot-Aided Neurorehabilitation: A Pediatric Robot for Ankle Rehabilitation

Abstract

This paper presents the pediAnklebot, an impedance-controlled low-friction, backdriveable robotic device developed at the Massachusetts Institute of Technology that trains the ankle of neurologically impaired children of ages 6-10 years old. The design attempts to overcome the known limitations of the lower extremity robotics and the unknown difficulties of what constitutes an appropriate therapeutic interaction with children. The robot's pilot clinical evaluation is on-going and it incorporates our recent findings on the ankle sensorimotor control in neurologically intact subjects, namely the speed-accuracy tradeoff, the deviation from an ideally smooth ankle trajectory, and the reaction time. We used these concepts to develop the kinematic and kinetic performance metrics that guided the ankle therapy in a similar fashion that we have done for our upper extremity devices. Here we report on the use of the device in at least 9 training sessions for 3 neurologically impaired children. Results demonstrated a statistically significant improvement in the performance metrics assessing explicit and implicit motor learning. Based on these initial results, we are confident that the device will become an effective tool that harnesses plasticity to guide habilitation during childhood.

Compliance adaptation of an intrinsically soft ankle rehabilitation robot driven by pneumatic muscles

“…Similarly, the compliance of the robot is adapted to a high level if the subjects show greater effort, which will allow more freedoms for the subject to deviate from reference trajectories. Such treatment strategy has been widely accepted by many clinical and engineering professionals [10,26,27].…”

Design and Performance Evaluation of a Novel Wearable Parallel Mechanism for Ankle Rehabilitation

“…Two linear actuators were arranged in parallel to aid recovery of PL/DO and inversion/eversion (IN/EV), while the adduction/ abduction (AD/AB) can be achieved via the rotation of the leg. Subsequently, a scaled down version called pediAnklebot (Michmizos et al, 2015) is developed for pediatric rehabilitation. Fan and Yin (2009) presented an ankle exoskeleton with a 3-RPS (revolute-prismatic-spherical) parallel mechanism as the main mechanical structure in cooperation with an electromyographic-based neuro-fuzzy controller.…”

Prototype of an Ankle Neurorehabilitation System with Heuristic BCI Using Simplified Fuzzy Reasoning

“…Early rehabilitation is necessary to treat hemiplegia. Training to improve range of motion and muscle strength is typically conducted using a continuous passive motion (CPM) device [3,4]. However, such efforts are ineffective after the chronic phase more than six months after cerebral infarction.…”

“…Thus, ankle joint rehabilitation is emphasized, because it is indispensable in forming a prosperous and vigorous society with elderly people living longer, maintaining and improving their activities of daily life (ADLs) and quality of life (QOL) and maintaining their ability to walk independently. Rehabilitation related to the ankle is of interest because (1) although several studies have addressed lower limb issues such as ankle control and improvement [4,11], fewer studies have examined BCI, except as related to the upper limbs; and (2) generally speaking, gait is a universal behavior involving the ankle, which is an important structure supporting body weight. Consequently, constructing ankle rehabilitation devices is a crucially important issue related to BCI.…”