The study of impedance control of lower extremity exoskeleton

2020 ◽  
Author(s):  
Yali Han ◽  
Jinfei Shi ◽  
Han Sun ◽  
Weijie Zhou ◽  
Hongyao Guan ◽  
...  
Keyword(s):  
Lower Extremity ◽  
Impedance Control

A robotic system with reinforcement learning for lower extremity hemiparesis rehabilitation

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jiajun Xu ◽  
Linsen Xu ◽  
Gaoxin Cheng ◽  
Jia Shi ◽  
Jinfu Liu ◽  
...  
Keyword(s):  
Reinforcement Learning ◽  
Lower Extremity ◽  
Muscle Activation ◽  
High Efficiency ◽  
Impedance Control ◽  
Robotic System ◽  
Mirror Therapy ◽  
Content Type ◽  
Model Reference Adaptive ◽  
Rehabilitation Exercise

Purpose This paper aims to propose a bilateral robotic system for lower extremity hemiparesis rehabilitation. The hemiplegic patients can complete rehabilitation exercise voluntarily with the assistance of the robot. The reinforcement learning is included in the robot control system, enhancing the muscle activation of the impaired limbs (ILs) efficiently with ensuring the patients’ safety. Design/methodology/approach A bilateral leader–follower robotic system is constructed for lower extremity hemiparesis rehabilitation, where the leader robot interacts with the healthy limb (HL) and the follow robot is worn by the IL. The therapeutic training is transferred from the HL to the IL with the assistance of the robot, and the IL follows the motion trajectory prescribed by the HL, which is called the mirror therapy. The model reference adaptive impedance control is used for the leader robot, and the reinforcement learning controller is designed for the follower robot. The reinforcement learning aims to increase the muscle activation of the IL and ensure that its motion can be mastered by the HL for safety. An asynchronous algorithm is designed by improving experience relay to run in parallel on multiple robotic platforms to reduce learning time. Findings Through clinical tests, the lower extremity hemiplegic patients can rehabilitate with high efficiency using the robotic system. Also, the proposed scheme outperforms other state-of-the-art methods in tracking performance, muscle activation, learning efficiency and rehabilitation efficacy. Originality/value Using the aimed robotic system, the lower extremity hemiplegic patients with different movement abilities can obtain better rehabilitation efficacy.

Combining Values

2002 ◽  
Vol 7 (2) ◽  
pp. 1-4, 12 ◽  
Author(s):  
Christopher R. Brigham
Keyword(s):  
Lower Extremity ◽  
Upper Extremity ◽  
Evaluation Method ◽  
Proximal Phalanx ◽  
Common Error ◽  
The Third ◽  
Whole Person ◽  
Impairment Ratings ◽  
Upper Extremity Impairment ◽  
The Individual

Abstract To account for the effects of multiple impairments, evaluating physicians must provide a summary value that combines multiple impairments so the whole person impairment is equal to or less than the sum of all the individual impairment values. A common error is to add values that should be combined and typically results in an inflated rating. The Combined Values Chart in the AMA Guides to the Evaluation of Permanent Impairment, Fifth Edition, includes instructions that guide physicians about combining impairment ratings. For example, impairment values within a region generally are combined and converted to a whole person permanent impairment before combination with the results from other regions (exceptions include certain impairments of the spine and extremities). When they combine three or more values, physicians should select and combine the two lowest values; this value is combined with the third value to yield the total value. Upper extremity impairment ratings are combined based on the principle that a second and each succeeding impairment applies not to the whole unit (eg, whole finger) but only to the part that remains (eg, proximal phalanx). Physicians who combine lower extremity impairments usually use only one evaluation method, but, if more than one method is used, the physician should use the Combined Values Chart.

Quick Reference: Chapter 3: The Musculoskeletal System and Chapter 4: The Nervous System

2000 ◽  
Vol 5 (3) ◽  
pp. 4-4
Keyword(s):  
Nervous System ◽  
Lower Extremity ◽  
Musculoskeletal System ◽  
Multistep Method ◽  
Manual Muscle Testing ◽  
Motor Deficits ◽  
Lower Extremity Weakness ◽  
Residual Symptoms ◽  
Muscle Testing ◽  
Almost All

Abstract Lesions of the peripheral nervous system (PNS), whether due to injury or illness, commonly result in residual symptoms and signs and, hence, permanent impairment. The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fourth Edition, divides PNS deficits into sensory and motor and includes pain in the former. This article, which regards rating sensory and motor deficits of the lower extremities, is continued from the March/April 2000 issue of The Guides Newsletter. Procedures for rating extremity neural deficits are described in Chapter 3, The Musculoskeletal System, section 3.1k for the upper extremity and sections 3.2k and 3.2l for the lower limb. Sensory deficits and dysesthesia are both disorders of sensation, but the former can be interpreted to mean diminished or absent sensation (hypesthesia or anesthesia) Dysesthesia implies abnormal sensation in the absence of a stimulus or unpleasant sensation elicited by normal touch. Sections 3.2k and 3.2d indicate that almost all partial motor loss in the lower extremity can be rated using Table 39. In addition, Section 4.4b and Table 21 indicate the multistep method used for spinal and some additional nerves and be used alternatively to rate lower extremity weakness in general. Partial motor loss in the lower extremity is rated by manual muscle testing, which is described in the AMA Guides in Section 3.2d.

Q&A: Multiple Lower Extremity Impairments and AMA Guides, Third Edition, Revised

2017 ◽  
Vol 22 (2) ◽  
pp. 15-16
Author(s):  
Christopher R. Brigham ◽  
Kathryn Mueller ◽  
Steven Demeter ◽  
Randolph Soo Hoo
Keyword(s):  
Lower Extremity

Spinal Impairment Evaluation: Fifth Edition Changes

2001 ◽  
Vol 6 (1) ◽  
pp. 1-3
Author(s):  
Robert H. Haralson
Keyword(s):  
Spinal Cord ◽  
Lower Extremity ◽  
Range Of Motion ◽  
Upper Extremity ◽  
Spinal Cord Injuries ◽  
Clinical Findings ◽  
Fourth Edition ◽  
Treatment Results ◽  
Standard Terminology ◽  
Made In

Abstract The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fifth Edition, was published in November 2000 and contains major changes from its predecessor. In the Fourth Edition, all musculoskeletal evaluation and rating was described in a single chapter. In the Fifth Edition, this information has been divided into three separate chapters: Upper Extremity (13), Lower Extremity (14), and Spine (15). This article discusses changes in the spine chapter. The Models for rating spinal impairment now are called Methods. The AMA Guides, Fifth Edition, has reverted to standard terminology for spinal regions in the Diagnosis-related estimates (DRE) Method, and both it and the Range of Motion (ROM) Method now reference cervical, thoracic, and lumbar. Also, the language requiring the use of the DRE, rather than the ROM Method has been strengthened. The biggest change in the DRE Method is that evaluation should include the treatment results. Unfortunately, the Fourth Edition's philosophy regarding when and how to rate impairment using the DRE Model led to a number of problems, including the same rating of all patients with radiculopathy despite some true differences in outcomes. The term differentiator was abandoned and replaced with clinical findings. Significant changes were made in evaluation of patients with spinal cord injuries, and evaluators should become familiar with these and other changes in the Fifth Edition.

Replantation of the Lower Extremity

1983 ◽  
Vol 10 (1) ◽  
pp. 103-113 ◽  
Author(s):  
Zhong-Wei Chen ◽  
Bing-Fang Zeng
Keyword(s):  
Lower Extremity
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