Tactile sensors systems are very important for today's service robotics. Designed as a holohedral cover for a robot, they are suitable for collision detection when working in unstructured environments, for humanmachine interaction or, with a high resolution, as object sensors enabling dexterous hands for reactive gripping. In this paper, we explain construction and working principle of resistive tactile sensor cells. The latter is based on the change of the electrical resistance between a conductive polymer and at least two electrodes. For this effect, we formulate a model to describe the dependence between the sensor's electrical resistance and the applied load. The model enables further improvements of resistive tactile sensor cells.

No abstract

By collisions with argon atoms in the gas phase (SORI‐CAD experiments by means of FT‐ICR mass spectrometry) the metalloid cluster ion [Ga19(C(SiMe3)3)6]— fragments in a very precise way detaching step by step neutral Ga(C(SiMe3)3) units and finally leading to the stable 40‐electron bare metal cluster [Ga13]—. In combination with quantum chemical calculations the exploration of the fragmentation process leads to an experimentally based understanding of the bond properties of many of the recently investigated metalloid gallium and aluminum clusters.

No abstract

Several prototype Cable-In-Conduit-Conductors (CICC) for the superconducting EDIPO (Efda DIPOle) revealed a degradation of their critical current (Ic) increasing with each loading cycle. The strong Lorentz-forces during operation in combination with the limited support of the single strands against these forces are thought to be the cause of the permanent degradation of the brittle Nb3Sn superconductor from which the multi-stranded CICC are made. In summer 2006 EFDA started to explore the possibility to remedy the Ic degradation by solder-filling the conductor in order to mechanically stabilize the twistedstrand cable inside the conduit. This solution was not considered as the main one, but as an emergency solution to be applied to the completed magnet, should every other option fail. The solder-filling approach was previously applied with success in some cases. Some issues, however, needed to be clarified before this solution could be proposed for the EDIPO project. The most important among them are the choice of solder material, details of the solder filling process, and the thermo-mechanical implications of a solder-filled, high-field, high-current cable. This work, being reported here, made use not only of simulation but also of experiments, such as the mechanical testing of solder filled cables at cryogenic temperatures.