Force control of upper limb exoskeleton to support user movement

Wheelchair mounted upper limb exoskeletons offer an alternative way to support disabled individuals in their activities of daily living (ADL). Key challenges in exoskeleton technology include innovative mechanical design and implementation of a control method that can assure a safe and comfortable interaction between the human upper limb and exoskeleton. In this article, we present a mechanical design of a four degrees of freedom (DOF) wheelchair mounted upper limb exoskeleton. The design takes advantage of non-backdrivable mechanism that can hold the output position without energy consumption and provide assistance to the completely paralyzed users. Moreover, a PD-based trajectory tracking control is implemented to enhance the performance of human exoskeleton system for two different tasks. Preliminary results are provided to show the effectiveness and reliability of using the proposed design for physically disabled people.

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A Novel Inverse Kinematics Method for Upper-Limb Exoskeleton under Joint Coordination Constraints

2020 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) ◽

10.1109/iros45743.2020.9341686 ◽

2020 ◽

Author(s):

Stefano Dalla Gasperina ◽

Keya Ghonasgi ◽

Ana C. de Oliveira ◽

Marta Gandolla ◽

Alessandra Pedrocchi ◽

...

Keyword(s):

Upper Limb ◽

Inverse Kinematics ◽

Joint Coordination ◽

Upper Limb Exoskeleton

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Sensor Reduction, Estimation, and Control of an Upper-Limb Exoskeleton

IEEE Robotics and Automation Letters ◽

10.1109/lra.2021.3056366 ◽

2021 ◽

pp. 1-1

Author(s):

Jianwei Sun ◽

Yang Shen ◽

Jacob Rosen

Keyword(s):

Upper Limb ◽

Upper Limb Exoskeleton ◽

Estimation And Control ◽

Sensor Reduction ◽

And Control

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Kinematic of the Position and Orientation Synchronization of the Posture of a n DoF Upper-Limb Exoskeleton with a Virtual Object in an Immersive Virtual Reality Environment

Electronics ◽

10.3390/electronics10091069 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1069

Author(s):

Deyby Huamanchahua ◽

Adriana Vargas-Martinez ◽

Ricardo Ramirez-Mendoza

Keyword(s):

Virtual Reality ◽

Upper Limb ◽

Human Performance ◽

Early Stage ◽

Inverse Kinematic ◽

Virtual Object ◽

Immersive Virtual Reality ◽

Virtual Reality Environment ◽

Upper Limb Exoskeleton ◽

Position And Orientation

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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