Modulation of Impedance and Muscle Activation of the Upper Limb Joints while Simultaneously Controlling Manual-grasping and Walking

Joseph Mizrahi, Navit Roth, Rahamim Seliktar

2017

Abstract

The design of spring-based artificial and robotic arm joints presents a challenge in problems of transportation of manually-held objects during walking. For maintaining stability of these objects, stiffness and damping of the arm joints have to be adjusted by continuously tuning muscle activation. This necessitates knowledge about the mechanisms by which stiffness and damping (mechanical impedance) are being modulated in walking movement. The paradigm employed in this study consisted of modeling the impedance adjustments from input data obtained in simultaneously controlled grasping and walking experiments. While walking on a treadmill, tested subjects held a cup filled with liquid and were asked to aim at minimizing liquid spillage. Monitoring liquid spillage served to quantify stability of the hand as the end-effector of the upper limb. Kinematic data were obtained for the shoulder, elbow and wrist joints. Accelerometer data were obtained for the wrist and for the knee. Electro-myography (EMG) data were collected for the wrist flexor and extensor muscles. Based on the measured data, regressive functions were used to express stiffness and damping as a function of angle and angular velocity. The joints of the upper limb were thereafter successively constrained to study the effect of joint immobilization on joint impedance and muscle activation. The obtained results indicate the nonlinearity of the joint impedances as required in tasks of manual grasping of objects during locomotion, with and without joint constraints.

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Paper Citation


in Harvard Style

Mizrahi J., Roth N. and Seliktar R. (2017). Modulation of Impedance and Muscle Activation of the Upper Limb Joints while Simultaneously Controlling Manual-grasping and Walking. In - BIODEVICES, (BIOSTEC 2017) ISBN , pages 0-0. DOI: 10.5220/0006239100001488


in Bibtex Style

@conference{biodevices17,
author={Joseph Mizrahi and Navit Roth and Rahamim Seliktar},
title={Modulation of Impedance and Muscle Activation of the Upper Limb Joints while Simultaneously Controlling Manual-grasping and Walking},
booktitle={ - BIODEVICES, (BIOSTEC 2017)},
year={2017},
pages={},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0006239100001488},
isbn={},
}


in EndNote Style

TY - CONF

JO - - BIODEVICES, (BIOSTEC 2017)
TI - Modulation of Impedance and Muscle Activation of the Upper Limb Joints while Simultaneously Controlling Manual-grasping and Walking
SN -
AU - Mizrahi J.
AU - Roth N.
AU - Seliktar R.
PY - 2017
SP - 0
EP - 0
DO - 10.5220/0006239100001488