This study presents a new method for the estimation of the dynamic impedance of multi-joint leg movements. The method is based on Multi Input Multi Output (MIMO) system identification techniques and is designed for continuous torque perturbations at the hip and knee joint. Preliminary results from this study indicate that MIMO system identification can successfully be used to estimate the hip and knee impedance and the interaction dynamics between both joints. It is also concluded that, in order to create a good model representation of the leg impedance, the effect of biarticular muscles needs to be taken into account. The obtained measures for joint impedance might be used for clinical assessment and follow up of patients, as well as for the development of supportive devices.

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This paper describes a system that provides a full body, digitally programmed, kinesthetic display for virtual reality applications. This design begins by providing a full six axis motion platform for each foot of the operator. From this base design, kneeling boards are added to support rolling, kneeling and prone postures; and a vertical feature presentation mechanism is appended which allows the operator to interact with realistic walls, windows, doors and other vertical obstacles features in his movement space. The design of this complex device was driven by a variety of requirements including the need for system modularity, enhanced safety and the need to emulate all significant physical activities

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In this paper we propose a framework for synchronization based control (SBC) using neural oscillators for motion assist. A neural oscillator is used to accomplish synchronization and entrainment between periodic motions by the human and robot. The mutual joint torque between the human and robot is used as an external input signal for the neural oscillator, which generates the desired trajectory of a robot joint angle, so that the robot motion synchronizes with the external mutual joint torque. The validity and feasibility of the proposed method is examined from three points of view. The first is whether synchronization of action between human and robot can be realized. The second is whether the assist effect can be obtained, and the third is whether the proposed method has an acceptable level of usability for the user. We explored those three points of view by conducting computer simulations on a human-motion assist system and experiments with a joint torque sensing robot suit.

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A «muscle suit» that provides muscular support for the paralyzed or those otherwise unable to move unaided is being developed as a wearable robot. The lack of a metal frame and use of McKibben artificial muscle allow the muscle suit to be lightweight, making it realistic to use in daily life. Although all motion for the upper limb by the armor type muscle suit with the mechanical joints and hard frame is realized, shoulder joints has difficulty in smooth motion because of DOF limitation. To overcome the limitation, new link mechanism is proposed and smooth motion for shoulder is achieved.

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The paper deals with the preliminary treatment of the problem of the determination of the relationship between the kinematics and the effective set of wrenches that a mechanical device can exert on the limbs of a human operator. The definition of force replicating devices (FRDs) is given together with a first classification related to their topological features. The analysis of force replication is initially carried out by considering the kinetostatic analysis for a generic mechanical device: the set of replicable wrenches is calculated on the basis of its kinematics properties. Examples are gives by considering two different types of FRD. The aim of the research is the determination of the kinematics features of an ideal FRD capable of replicating the desired set of wrenches to the specific human body part

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