The control of exploratory and manipulative procedures in Teleoperation and Virtual Environments requires the availability of adequate advanced interfaces capable not only of recording the movements of the human hands and arms, but also of replicating sensations of contact and collisions. In this paper the problem of replicating external forces acting against the remote/virtual a r m is addressed. The design of an arm exoskeleton system developed an our laboratory is presented. The exoskeleton consists of a 7 actuated and sensorized DOF mechanical structure wrapping up completely the human arm and directly supported by the shoulders and the trunk of the human operator. Emphasis is given t o the implemented control procedures and t o the description of the transputer-based control architecture.

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A new integrated system consisting of a testing machine, denominated Diaptometro, and of an algorithm for metallic materials identification via instrumented spherical indentation testing is presented. The identification is carried out by analyzing the experimental load – penetration depth curve ( curve) from shallow indentation tests, thus preventing any contact condition effects in the material properties estimation. Accuracy in the experimental data collecting and the curve representation were recognized to be the key factors at the basis of reliable and accurate estimations. A new equipment with accuracies of 0.075% and 0.1% for the penetration depth and indentation load respectively was specifically built-up, whereas a four-terms power expansion is proposed for modeling the curve in the identification procedure. Experimental validation campaigns confirm the effectiveness of the adopted solutions.

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