A new concept of the exoskeleton-type masterarm, composed of serial links, is introduced in this paper. To provide maximum range of human motion, several redundant joints are added to the serial links. In order to reduce the number of joints to be measured, kinematics of serial links was taken into consideration in design. Three measurable, controllable joints and three redundant free joints are used for the upper arm (shoulder), similarly to the forearm (wrist) while one measurable, controllable joint is used for the elbow. In particular, a torque sensor beam is designed for fine force reflection using the strain gauge. It detects the torque as well as its direction applied by the human operator, which allows the electric brake to be used as an actuator for force reflection. The electric brake constrains the joint movement so that the operator can feel the force. This electric brake outperforms the motor in terms of torque/weight ratio and makes the device light and compact. This masterarm measures the movement of the operator’s arm precisely, and it can be used for teleoperation with a slave robot, or as a motion planner for an industrial robot.

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Integrating humans and robotic machines into one system offers multiple opportunities for creating assistive technologies that can be used in biomedical, industrial, and aerospace applications. The scope of the present research is to study the integration of a human arm with a powered exoskeleton (orthotic device) and its experimental implementation in an elbow joint, naturally controlled by the human. The Human–Machine interface was set at the neuromuscular level, by using the neuromuscular signal (EMG) as the primary command signal for the exoskeleton system. The EMG signal along with the joint kinematics were fed into a myoprocessor (Hill-based muscle model) which in turn predicted the muscle moments on the elbow joint. The moment-based control system integrated myoprocessor moment prediction with feedback moments measured at the human arm/exoskeleton and external load/exoskeleton interfaces. The exoskeleton structure under study was a two-link, two-joint mechanism, corresponding to the arm limbs and joints, which was mechanically linked (worn) by the human operator. In the present setup the shoulder joint was kept fixed at given positions and the actuator was mounted on the exoskeleton elbow joint. The operator manipulated an external weight, located at the exoskeleton tip, while feeling a scaled-down version of the load. The remaining external load on the joint was carried by the exoskeleton actuator. Four indices of performance were used to define the quality of the human/machine integration and to evaluate the operational envelope of the system. Experimental tests have shown that synthesizing the processed EMG signals as command signals with the external-load/human-arm moment feedback, significantly improved the mechanical gain of the system, while maintaining natural human control of the system, relative to other control algorithms that used only position or contact forces. The results indicated the feasibility of an EMG-based power exoskeleton system as an integrated human–machine system using high- level neurological signals.

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A band controlled valve apparatus for controlling fluid flow from a source to a sink, including a base (12) having an upper surface and an aperture (16) extending from the upper surface through the base (12) allowing the flow of fluid from the source through the base (12) to the sink when the aperture (16) is not covered, an elongate flexible band (8) with a first portion (8a) in contact with the upper surface of the base (12) and a second portion (8b) extending forwardly of the first portion (8a) then upwardly and rearwardly above at least a part of the first portion (8a), the second portion (8b) being actuated to selectively move the second portion (8b) of the band (8) forwardly or rearwardly to cover or uncover, respectively, the aperture (16) with the first portion (8a) of the band (8) to thereby prevent or allow, respectively, fluid flow through the aperture (16).

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A rotary displacement measuring apparatus includes an axle whose rotary displacement is to be determined, with the axle being mounted to rotate about its long axis. An emitter disk is mounted on the axle to define a plurality of concentric tracks circumscribing the axle to rotate as the axle rotates, with each of the tracks being segmented to define a plurality of spaced-apart, conductive sections for producing electric fields when energized. Also included is a voltage source for energizing the conductive sections. A detector is disposed adjacent to the tracks of the emitter disk and includes a plurality of sensors, each positioned adjacent a respective track to detect the electric fields of the respective track as the axle and tracks are rotated. The detector produces signals representing the detection of the electric fields as the emitter disk is rotated, and these signals provide an indication of the rotary displacement of the tracks and thus of the axle.

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This paper deals with a particular aspect of the research on teleopera-tion and on the interaction with Virtual Environments (VE), i.e. the design and the development of man-machine interfaces. These systems must be adequate to both record the movements of the human operator’s hand and arms and replicate on them forces detected by the end-effector of the remote robot, or modelled in the VE, at the interaction with the external, or virtual environment. In particular issues related to force replication to the human operator are considered. At first the set of requirements needed for the Force Display Device (FDD) to allow the human operator to perform a good control of manipulative and exploratory tasks are presented. Such issues as manoeuvrability, fidelity, transparency or passivity of the FDD will be addressed. Two basic topologies of FDDs are analyzed in terms of workspaces and force replication. The work carried out at Scuola Superiore S.Anna for the development of FDDs is then presented. In particular two prototypes of Arm and Hand Exoskeletons are described in detail together with the experiments carried out up to now by exploiting a virtual environment testing scenario. The approach to the design of a second prototype of Arm Exoskeleton, devised for application in the rehabilitation field, is presented.

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