Force control of an upper limb exoskeleton for virtual reality using impedance control

Exoskeletons are an external structural mechanism with joints and links that work in tandem with the user, which increases, reinforces, or restores human performance. Virtual Reality can be used to produce environments, in which the intensity of practice and feedback on performance can be manipulated to provide tailored motor training. Will it be possible to combine both technologies and have them synchronized to reach better performance? This paper consists of the kinematics analysis for the position and orientation synchronization between an n DoF upper-limb exoskeleton pose and a projected object in an immersive virtual reality environment using a VR headset. To achieve this goal, the exoskeletal mechanism is analyzed using Euler angles and the Pieper technique to obtain the equations that lead to its orientation, forward, and inverse kinematic models. This paper extends the author’s previous work by using an early stage upper-limb exoskeleton prototype for the synchronization process.

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Direct force control of upper-limb exoskeleton based on fuzzy adaptive algorithm

Journal of Vibroengineering ◽

10.21595/jve.2017.18610 ◽

2018 ◽

Vol 20 (1) ◽

pp. 636-650 ◽

Cited By ~ 1

Author(s):

Yang Wang ◽

Jing Tang ◽

Jianbin Zheng

Keyword(s):

Upper Limb ◽

Force Control ◽

Adaptive Algorithm ◽

Upper Limb Exoskeleton ◽

Fuzzy Adaptive

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The Control of an Upper-Limb Exoskeleton by Means of a Particle Swarm Optimized Active Force Control for Motor Recovery

IFMBE Proceedings - 3rd International Conference on Movement, Health and Exercise ◽

10.1007/978-981-10-3737-5_12 ◽

2017 ◽

pp. 56-62

Author(s):

A. P. P. Abdul Majeed ◽

Z. Taha ◽

I. Mohd Khairuddin ◽

M. Y. Wong ◽

M. A. Abdullah ◽

...

Keyword(s):

Upper Limb ◽

Force Control ◽

Particle Swarm ◽

Motor Recovery ◽

Active Force ◽

Upper Limb Exoskeleton ◽

Active Force Control

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Hybrid Impedance-Admittance Control for Upper Limb Exoskeleton Using Electromyography

Applied Sciences ◽

10.3390/app10207146 ◽

2020 ◽

Vol 10 (20) ◽

pp. 7146

Author(s):

Lucas D. L. da Silva ◽

Thiago F. Pereira ◽

Valderi R. Q. Leithardt ◽

Laio O. Seman ◽

Cesar A. Zeferino

Keyword(s):

Upper Limb ◽

Degrees Of Freedom ◽

Control Method ◽

Hybrid Control ◽

Impedance Control ◽

Robotic Arm ◽

Average Error ◽

Acceptable Error ◽

Upper Limb Exoskeleton ◽

Input Signals

Exoskeletons are wearable mobile robots that combine various technologies to enable limb movement with greater strength and endurance, being used in several application areas, such as industry and medicine. In this context, this paper presents the development of a hybrid control method for exoskeletons, combining admission and impedance control based on electromyographic input signals. A proof of concept of a robotic arm with two degrees of freedom, mimicking the functions of a human’s upper limb, was built to evaluate the proposed control system. Through tests that measured the discrepancy between the angles of the human joint and the joint of the exoskeleton, it was possible to determine that the system remained within an acceptable error range. The average error is lower than 4.3%, and the robotic arm manages to mimic the movements of the upper limbs of a human in real-time.

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