Wrist joint torque-angle-velocity performance capacity envelope evaluation and modelling

A biomechanical model of the press handstand was developed to evaluate and predict the shoulder joint torque requirements as well as the motion of a gymnast’s center of mass (CM) from an initial to a final (handstand) position. Five press handstands executed by gymnasts of differing abilities were filmed and analyzed. The results were compared to the predicted parameters of simulated presses. It was found that execution of the skill with fewer fluctuations in trunk and lower extremities angular velocity—a characteristic of skilled performance—required smoother and at times larger shoulder joint torques. Reduction of the hip joint angle by only 5 or 10° did not substantially reduce the shoulder joint torque requirements. Regarding CM motion, it was found that during performance the CM continuously elevated and remained close to a vertical line passing through the center of the wrist joint. All gymnasts, however, were found to be leaning slightly backward during the first part of the movement and slightly forward during the later phases. Modifications in wrist joint angle required to maintain each gymnast’s CM precisely above the center of the wrist joint were investigated.

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Provocative mechanical tests of the peripheral nervous system affect the joint torque-angle during passive knee motion

Scandinavian Journal of Medicine and Science in Sports ◽

10.1111/sms.12250 ◽

2014 ◽

Vol 25 (3) ◽

pp. 338-345 ◽

Cited By ~ 3

Author(s):

R. J. Andrade ◽

S. R. Freitas ◽

J. R. Vaz ◽

P. M. Bruno ◽

P. Pezarat-Correia

Keyword(s):

Nervous System ◽

Peripheral Nervous System ◽

Mechanical Tests ◽

Joint Torque ◽

Knee Motion ◽

Torque Angle

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Wrist torque estimation during simultaneous and continuously changing movements: surface vs. untargeted intramuscular EMG

Journal of Neurophysiology ◽

10.1152/jn.00086.2013 ◽

2013 ◽

Vol 109 (11) ◽

pp. 2658-2665 ◽

Cited By ~ 25

Author(s):

Ernest N. Kamavuako ◽

Erik J. Scheme ◽

Kevin B. Englehart

Keyword(s):

Degrees Of Freedom ◽

Performance Metrics ◽

Wrist Joint ◽

Pearson Correlation ◽

Surface Emg ◽

Joint Torque ◽

Coefficient Of Determination ◽

Significant Difference ◽

The Difference ◽

The Right

In this paper, the predictive capability of surface and untargeted intramuscular electromyography (EMG) was compared with respect to wrist-joint torque to quantify which type of measurement better represents joint torque during multiple degrees-of-freedom (DoF) movements for possible application in prosthetic control. Ten able-bodied subjects participated in the study. Surface and intramuscular EMG was recorded concurrently from the right forearm. The subjects were instructed to track continuous contraction profiles using single and combined DoF in two trials. The association between torque and EMG was assessed using an artificial neural network. Results showed a significant difference between the two types of EMG ( P < 0.007) for all performance metrics: coefficient of determination (R2), Pearson correlation coefficient (PCC), and root mean square error (RMSE). The performance of surface EMG (R2 = 0.93 ± 0.03; PCC = 0.98 ± 0.01; RMSE = 8.7 ± 2.1%) was found to be superior compared with intramuscular EMG (R2 = 0.80 ± 0.07; PCC = 0.93 ± 0.03; RMSE = 14.5 ± 2.9%). The higher values of PCC compared with R2 indicate that both methods are able to track the torque profile well but have some trouble (particularly intramuscular EMG) in estimating the exact amplitude. The possible cause for the difference, thus the low performance of intramuscular EMG, may be attributed to the very high selectivity of the recordings used in this study.

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Knee and ankle joint torque–angle relationships of multi-joint leg extension

Journal of Biomechanics ◽

10.1016/j.jbiomech.2011.05.011 ◽

2011 ◽

Vol 44 (11) ◽

pp. 2059-2065 ◽

Cited By ~ 25

Author(s):

Daniel Hahn ◽

Matthias Olvermann ◽

Jan Richtberg ◽

Wolfgang Seiberl ◽

Ansgar Schwirtz

Keyword(s):

Ankle Joint ◽

Joint Torque ◽

Leg Extension ◽

Torque Angle

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Torque-Angle Relationship for a 2D RRR-Type Serial Link Manipulator

Advanced Science Engineering and Medicine ◽

10.1166/asem.2020.2584 ◽

2020 ◽

Vol 12 (10) ◽

pp. 1296-1299

Author(s):

Anil Kumar Gillawat ◽

Hemant Jayantilal Nagarsheth

Keyword(s):

Joint Torque ◽

Serial Links ◽

Serial Link ◽

Joint Torques ◽

Serial Manipulators ◽

Revolute Joints ◽

Euler Approach ◽

Torque Values ◽

Torque Angle ◽

Selection Of

This paper presents an application of Lagrange–Euler approach for dynamic analysis of three link with revolute type (RRR-type) rigid serial manipulators. MATLAB code is programmed for Lagrange– Euler approach for RRR-type serial manipulator for generating joint torque equations and plotting these joint torque values for given range of angular rotations. This study is useful for understanding the effect of combinations of link rotation on joint torque behaviour. Maximum value of required joint torques obtained can be used for selection of motors for any mechanism with serial links with revolute joints performing given task.

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A Basic Study on Biological Signal of Operator During Master-Slave System Control

Journal of Robotics and Mechatronics ◽

10.20965/jrm.2012.p0908 ◽

2012 ◽

Vol 24 (5) ◽

pp. 908-916 ◽

Cited By ~ 1

Author(s):

Yu Okamoto ◽

◽

Kotaro Tadano ◽

Kenji Kawashima ◽

Keyword(s):

External Force ◽

Visual Information ◽

Wrist Joint ◽

Early Stage ◽

Joint Torque ◽

Slave System ◽

Basic Study ◽

Biological Signals ◽

Acting Force ◽

Master Slave System

In a master-slave system, operators control the master device based on visual information and sensory feedback. This suggests that the position sensors on the slave side are not always necessary. However, position signals are required to estimate the acting force conveyed to the slave using an observer which realize the force sensorless control. In this paper, we focused on the biological signals of the operator to estimate the slave side’s condition which can be used to estimate the external force. In the early stage of the research, we investigate biological signals just with 1-DOF masterslave system. First, we measured electromyographic (EMG) and gripping force of operators when pushing objects. We verified that predictive signals can be used for estimation of touching the objects. Second, we propose a method, which uses wrist joint torque and Total Contraction Level (TCL) calculated by the EMG when pushing the virtual elastic films, of estimating the acting force conveyed to the slave. We verify that the proposed method can estimate external force under specific conditions with a trained subject.

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