EXOSTATION is a project aiming at building a complete haptic control station, which allows the operator wearing an exoskeleton-based haptic interface for the human arm to remotely control a virtual slave robot. This paper briefly describes the various components : the Sensoric Arm Master (SAM), a portable haptic exoskeleton, the Exoskeleton COntroller (ECO), the slave simulator, simulating an anthropomorphic manipulator and a 3D visualisation client. Several teleoperation control strategies (impedance, hybrid control, 3-channel) have been tested and compared in order to evaluate their performances. The last has shown the best behavior in term of haptic feedback. Finally, a focus is made on the application, and how various manipulation and operation tasks can be performed to assess the system’s performances (contact wall, objects manipulation, screwing). Users who tested the system were very impressed by the easiness of operation with the exoskeleton and felt the advantages of a force feedback information.

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Many people suffer from diseases that impair muscle function, resulting in decreased hand strength and a significant reduction in hand function. The objective of this project is to design and fabricate a powered exoskeleton that assists hand function and reduces the amount of muscular force needed to pinch and grasp. This device will be portable and easily manufactured, consisting of four major sub-systems: a mechanical exoskeleton, forearm support structure, biofeedback sensor array, and motor control system. The exoskeleton will be comprised of aluminum bands incorporated into a tight fitting glove. The mechanical exoskeletonwill be actuated using braided polymer cables attached to three linear actuators via a simple pulley system that connects the most distal finger bands to the motors. The control system of the hand will incorporate a microcontroller that is coded to integrate data from the finger tip sensors to actuate the motors. A light weight, portable battery will be utilized as the power supply.

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Force feedback from the virtual world can greatly enhance the sense of immersion even for simple applications. The ISU force reflecting exoskeleton enables the user to interact dynamically with simulated environments by providing an electro-magnetic haptic interface between the human and the environment. This paper describes the force and trajectory control interface for the PUMA 560 manipulator that supports the ISU force reflecting exoskeleton hand tracking system. The combined exoskeleton-PUMA system allows the application of virtual forces to the digits of the human finger. Two different typical synthetic environments are programmed and tested using the ISU force reflecting exoskeleton haptic interface device. The experimental results shows that the magnetic interface gives adequate force levels for perception of virtual objects, enhancing the feeling of immersion in the virtual environment, and that the PUMA 560 provides adequate tracking and free motion capabilities for the ISUexoskeleton system

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A human wearing an exoskeleton-type assistive device results in a parallel control system that includes two controllers: anexoskeleton controller and a human brain that includes the spinal cord and the cerebrum. Unknown and complicated characteristics of the brain dynamically interact with the exoskeleton controller, which makes the controller design challenging. In this paper, the motion control system of a human is regarded as a feedback control loop that consists of the brain, muscles, and the dynamics of the extended human body. The brain is modeled as a control algorithm amplified by a fictitious gain (FG). The FG is adjusted to compensate for characteristic changes in the muscle and human body dynamics due to physical impairment, varying load, or any other causes. In this paper, an exoskeleton controller that realizes the FG is designed, and its performance and robustness are discussed.

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In this paper we propose an upper body exoskeleton to augment a soldier’s ability to maneuver and fire a heavy weapon. After describing the initial design concept, we model the system dynamics both using Lagrange’s method and the SimMechanics software package. We derive a controller for our upper body exoskeleton, loosely inspired by the novel approach used on the Berkeley lower body exoskeleton (BLEEX). The approach is to combine the computed torque method, along with a nearly marginally stable linear feedback law. The resulting controller can track the wearer’s movement with without the need to measure muscular activation levels. We simulation results for the controller with a human torque input. The contributions, while modest, are an important first step in evaluating the feasibility of this approach for an upper body exoskeleton.

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