Passive Hydraulic Training Simulator for Upper Arm Spasticity

2020 ◽  
Vol 12 (4) ◽  
Author(s):  
Jiahui Liang ◽  
Yinan Pei ◽  
Randy H. Ewoldt ◽  
Steven R. Tippett ◽  
Elizabeth T. Hsiao-Wecksler
Keyword(s):  
Evaluation Method ◽  
Muscle Tone ◽  
Fluid Model ◽  
Angular Speed ◽  
Practical Training ◽  
Training Simulator ◽  
Damping Force ◽  
Upper Arm ◽  
Hydraulic Damper ◽  
Resistive Torque

Abstract Spasticity is a hypertonic muscle behavior commonly observed in patients with multiple sclerosis, cerebral palsy, stroke, etc. Clinical assessment for spasticity is done through passive stretch evaluations of various joints using qualitative clinical scales, such as the Modified Ashworth Scale (MAS). Due to the subjective nature of this evaluation method, diagnostic results can have poor reliability and inconsistency. A few research groups have developed electromechanical training simulators of upper arm spasticity with the intent of providing healthcare students practical training opportunities. This paper presents a novel, purely mechanical (nonpowered) training simulator as an alternative design approach. This passive design utilizes a hydraulic damper with selectable viscous effect to simulate the speed-dependent spastic muscle tone and a Scotch-Yoke linkage system to create the “catch-release” behavior of spasticity. An analytical fluid model was developed to systematically design the hydraulic damper. The error residuals between model prediction and experimental damping force were found within ±2.0 N and percent errors within ±10% across various testing speeds (i.e., 250, 500, 750, and 1000 mm/min). The performance of the fully assembled simulator was tested under slow (ω ≤ 60 deg/s), medium (60 deg/s < ω < 150 deg/s), and fast (ω ≥ 150 deg/s) stretch speeds, where ω is the joint angular speed. Preliminary bench-top results suggested the feasibility of replicating five distinct levels of spasticity behaviors (MAS levels 0–4), where resistive torque increased with higher stretch speed and peak resistive torque ranged from 1.3 to 6.7 N · m under the fast stretch speed.

Design Framework and Clinical Evaluation of a Passive Hydraulic Patient Simulator for Biceps Spasticity Assessment Training

2021 ◽  
Vol 13 (4) ◽  
Author(s):  
Yinan Pei ◽  
Randy H. Ewoldt ◽  
Christopher M. Zallek ◽  
Elizabeth T. Hsiao-Wecksler
Keyword(s):  
Mechanical Design ◽  
Muscle Tone ◽  
Training Simulator ◽  
Design Features ◽  
Resistance Level ◽  
Patient Simulator ◽  
Resistive Torque ◽  
Good Potential ◽  
The Mean ◽  
Assessment Training

Abstract This article presents the framework for developing a passive (unpowered) mechanical training simulator for replication of biceps spasticity to complement current clinical assessment training. The passive training simulator was developed to mimic three main behavioral features of spasticity, i.e., abnormal muscle tone, catch-release behavior, and range of motion (ROM) reduction. The simulator can replicate varied levels of spasticity (Modified Ashworth Scale (MAS) levels 0–4) using a combination of three adjustable mechanical design features, i.e., resistance level, catch angle, and ROM selectors. Bench-top evaluation examined the performance of individual mechanical design features, as well as their combined performance. Spastic muscle resistance profiles generated by the simulator qualitatively agreed with the clinical descriptions of spasticity in the MAS. Mean peak simulated resistive torque fell within the clinical measures from actual spasticity patients for MAS 1–4, but was lower for MAS 0 (0.9, 3.5, 4.2, 6.9, 9.8 Nm for MAS 0–4, respectively). Seven clinicians were invited to validate the simulator performance. They were asked to identify the simulated MAS level during a blinded assessment and to score the realism of each simulation feature using a five-point scale, where 3 was “about right,” during a disclosed assessment. The mean percent agreement of clinicians’ judgments was 76 ± 12%. The mean realism score throughout MAS 0–4 were 2.82 ± 0.15. Preliminary results suggested good potential for this simulator in helping future healthcare practitioners learn and practice the basics of spasticity assessment.

scholarly journals The Aerodynamics of a Diabolo

2021 ◽  
Author(s):  
Darren Jia
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Angular Momentum ◽  
Flow Pattern ◽  
High Spin ◽  
Angular Speed ◽  
Geometric Shape ◽  
Cfd Simulations ◽  
Resistive Torque ◽  
Computational Fluid Dynamics Cfd

Diabolo is a popular game in which the object can be spun at up to speeds of 5000 rpm. This high spin velocity gives the diabolo the necessary angular momentum to remain stable. The shape of the diabolo generates an interesting air flow pattern. The viscous air applies a resistive torque on the fast spinning diabolo. Through computational fluid dynamics (CFD) simulations it's shown that the resistive torque has an interesting dependence on the angular speed of the diabolo. Further, the geometric shape of the diabolo affects the dependence of torque on angular speed.

scholarly journals Revised Design of a Passive Hydraulic Training Simulator of Biceps Spasticity

2018 ◽  
Author(s):  
Yinan Pei ◽  
Randy H. Ewoldt ◽  
Christopher M. Zallek ◽  
Elizabeth T. Hsiao-Wecksler
Keyword(s):  
Neurological Disorders ◽  
Muscle Tone ◽  
Clinical Signs ◽  
Limited Range ◽  
Passive Movement ◽  
Sudden Increase ◽  
Release Behavior ◽  
Training Simulator ◽  
Limited Range Of Motion ◽  
Passive Stretch

Spasticity is a common abnormal muscle behavior associated with neurological disorders and is characterized by speed-dependent increased tone in the affected muscle when induced by passive movement [1]. During the passive stretch of the muscle, additional unique clinical signs that accompany spasticity are (a) sudden increase in muscle tone at a certain joint position (catch angle), called the “catch”, (b) after the “catch”, a quick drop of muscle resistance, called the “release”, where (a) and (b) together are usually referred to as the “catch-release” behavior, and (c) limited range of motion (ROM) [1,2]. With the evolution of spasticity, these symptoms will worsen.

scholarly journals DEVELOPMENT OF THE PROCEDURE OF TESTING WITH THE APPLICATION OF THE EXPERT EVALUATION METHOD IN PSYCHOPHYSIOLOGY

2019 ◽  
Vol 7 (5) ◽  
pp. 941-945
Author(s):  
Svetlana V. Igrunova ◽  
Elena V. Nesterova ◽  
Orest D. Ivaschuk ◽  
Valery G. Nesterov ◽  
Alexandr V. Lomazov ◽  
...  
Keyword(s):  
Information System ◽  
Evaluation Method ◽  
Influencing Factor ◽  
Practical Training ◽  
Expert Evaluation ◽  
Information System Design ◽  
Functional Models ◽  
Teachers And Students ◽  
Expert Evaluation Method ◽  
Psychophysiological Testing

Purpose: This article provides a detailed description of the stages of development of an information system of personalized psychophysiological testing using expert evaluation. The process of the information system design is presented, the developed functional models, database and algorithm of testing by students-experts are demonstrated. Methodology: As a result of the analysis, the features of commercial educational institutions in the field of practical psychology, as the main influencing factor can be identified as the amount of practical training in the direction of «Psychology», which is very different from the standard curriculum. Result: In the learning process, students, who acts experts, face following problems: absence of a clear structured hierarchy of indicators (test questions) in the evaluation of tests; lack of a procedure for formalization and evaluation of various qualitative and quantitative indicators (certain types of tests; lack of an effective tool that provides support for decision-making on the selection of personality type. The proposed system will solve these problems. Applications: This research can be used for universities, teachers, and students. Novelty/Originality: In this research, the model of Development of the Procedure of Testing with the Application of the Expert Evaluation Method in Psychophysiology is presented in a comprehensive and complete manner.

scholarly journals Enhancement of Damping Force of Classical Hydraulic Damper into Semi Active Damper using MR Approach

2019 ◽  
Vol 5 (4) ◽  
Author(s):  
Mane Shubham S. ◽  
Abhangrao Chaitanya R. ◽  
Kothawale Rajdeep R. ◽  
Mete Akash R. ◽  
Raut Laukik B.
Keyword(s):  
Damping Force ◽  
Hydraulic Damper ◽  
Active Damper

Numerical Evaluation and High-Speed Rotating Test On Circular Arc Spring Dampers for Centrifugal Compressors

2021 ◽  
Author(s):  
Ryota Takeuchi ◽  
Hidetsugu Ishimaru ◽  
Hideaki Yamashita ◽  
Takahiko Inoue ◽  
Shota Yabui ◽  
...  
Keyword(s):  
High Speed ◽  
Numerical Evaluation ◽  
Evaluation Method ◽  
Interaction Analysis ◽  
Flow Analysis ◽  
Theoretical Background ◽  
Fluid Film ◽  
System Level ◽  
Damping Force ◽  
Circular Arc

Abstract A circular arc spring damper (CASD) is a recently-proposed, compact fluid-film damper that has two or more arc-shaped centering springs and dual radial clearances. It provides linear stiffness and stable damping force in rotor-bearing systems. However, their performance and applicability to real machines have not been confirmed in system-level experiments. Additionally, a theoretical means of evaluation for CASD should be established. In the first part of this study, a numerical evaluation method using two-way fluid-structure interaction analysis and its theoretical background is presented. Transient structural analysis and fluid-film flow analysis with a simple homogeneous cavitation model are coupled in the commercial multi-physics platform ANSYS. The accuracy of the method was validated by comparing the damping and added-mass coefficients with results from previous experiments. Furthermore, several aspects of the force generation mechanism were studied numerically. The second part of the study addresses the application of CASD in a multi-stage centrifugal compressor. A combined 4-inch diameter tilting pad journal bearing (TPJB) with CASD was newly designed and manufactured. To prove the applicability of the developed damper bearing, a series of rotating tests was conducted at a high-speed balancing facility with a full-scale dummy rotor. The measured unbalance response showed a much lower amplification factor than that of the conventional TPJB without the damper. The measured responses agreed with the rotordynamic analysis, which uses the dynamic coefficients of CASD derived from the proposed numerical evaluation method.

Effects of MHD and wall properties on the peristaltic transport of a Carreau fluid through porous medium

2014 ◽  
Vol 6 (2) ◽  
pp. 1106-1121 ◽  
Author(s):  
Dheia Salih ◽  
Ahmed M. Abdulhadi M. Abdulhadi
Keyword(s):  
Porous Medium ◽  
Stream Function ◽  
Fluid Model ◽  
Darcy Number ◽  
Perturbation Series ◽  
Weissenberg Number ◽  
Carreau Fluid ◽  
Damping Force ◽  
Long Wavelength ◽  
Wall Properties

This work concerns the peristaltic flow of a Carreau fluid model through porous medium under combined effects of MHD and wall properties. The assumptions of Reynolds number and long wavelength is investigated. The flow is investigated in a wave frame of reference moving with velocity of the wave. The perturbation series in terms of the Weissenberg number (We <1) was used to obtain explicit forms for velocity field and stream function. The effects of thermal conductivity, Grashof number, Darcy number, magnet, rigidity, stiffness of the wall and viscous damping force parameters on velocity, temperature and stream function have been studied.

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