This paper presents the development of a novel functional electrical stimulation (FES) system. New approaches in emerging rehabilitation robotics propose the use of residual muscular activity or limbs movements during the rehabilitation process of neuromotor. More ambitious projects propose the use of FES systems to restore or compensate motor capabilities by controlling existing muscles or subject limbs. These emerging approaches require more sophisticated FES devices in terms of channels, signals controls and portability. In the framework of HYPER project, such devices are being developed to support the main objective of the project: the development of neurorobots and neuroprosthetics to restore functional motor capabilities in patients who suffered cerebrovascular accidents or spinal cord injury. The presented portable FES system includes novel elec-trostimulator circuits and improved channel switching capacities to enable emerging approaches in rehabilitation robotics.

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The short range atomic arrangements in crystalline chitin, crystalline chitosan and amorphous chitosan films are shown to be similar in that the fundamental rings and chains are retained in all of these structures. The interchain bonding differs, however, and is weakest in amorphous chitosan and strongest in crystalline chitin.

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To hear those in the know tell it, database management systems leave a lot to be desired: They require too much hardware, and they make poor use of it. Some advocate a shift in the type of hardware used¿away from the CPU toward graphics-processing units [see «Data Monster,» September 2009]. But opensource database firm Ingres, of Redwood City, Calif., and start-up VectorWise, of Amsterdam, see the answer in a better use of the CPU.

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Haptic interaction with virtual objects is typically tool mediated, or in alternative it constraints userpsilas body in someway, like it happens in exoskeletons that cannot be totally transparent. Encounter type haptic interfaces aim at hands free haptic interaction, that is more natural and can be applied in contexts in which the user moves in the space around the interface. This paper presents a system that allows a palm based haptic interaction in a large workspace using the principle of encountered haptics. The system is evaluated in a surface exploration task and compared against the same task performed with a standard haptic interface. In this type of task this type of interface is better suited, providing a smoother feedback to the hand during the movement over the surface.

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Developing a telerobot control system for a dexterous hand requires the integration of two very complex systems. The paper presents an approach for controlling the Stanford/JPL Dexterous Hand through a communications network, using an EXOS Dexterous Hand Master. The two major problems to be solved were: mapping of the output of the Hand Master into the corresponding input for the Dexterous Hand Controller, and delivery of the output of the Hand Master to the input of the Dexterous Hand Controller through a communications network in a timely manner. The approach consists of the following steps: division of the system into subsystems, determining the characteristics of individual subsystems, development of suitable mapping algorithms, development of an ancillary graphics subsystem to facilitate the integration of subsystems, and integrating the subsystems using a step by step approach. This approach resulted in process in which the analog signals from the Dexterous Hand Master were conditioned and then converted to digital integers. The integers were mapped into integers representing half degrees. The half degree integers were transmitted to Stanford/JPL Dexterous Hand Controller in data packets via an Ethernet 802.3 data link. The destination node of the data link extracted the half degree integers and input them to another subsystem which mapped them into Dexterous Hand Controller commands. These commands were used to control the Dexterous Hand. The process was implemented in the laboratory and used to successfully control a Stanford/JPL Dexterous Hand by an EXOS Dexterous Hand Master through an Ethernet data link

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