Piezoelectric stack actuators (PESAs) are widely used in applications requiring a fast response, high resolution, and accuracy. The self-heating of PESA during continuous drive with large amplitude at frequencies can change its voltage displacement charge characteristics. These changes lead to loss stability inaccurate positioning systems. In this paper, we confirmed that by using our proposed ...

A coupled thermal-microstructural simulation model was developed to estimate the thermal history in a eutectoid steel wire rod under continuous cooling and forced-convection. The phenomena of heat transfer, phase transformation estimation boundary condition. histories were analyzed at different rates emulate forced-convection conditions by air-jet as controlled conveyor. acquired used calculate...

BACKGROUND This pilot study in five healthy adult humans forms the pre-clinical assessment of the effect of a forced convective head cooling device on intracranial temperature, measured non-invasively by magnetic resonance spectroscopy (MRS). METHODS After a 10 min baseline with no cooling, subjects received 30 min of head cooling followed by 30 min of head and neck cooling via a hood and nec...

Shape Memory Alloys (SMA) are good candidates to actuate endoscope heads but the cooling problem must be solved particularly in confined situations. For these reasons, a new SMA microactuator specially designed for active endoscopy applications has been developed in our laboratory. This work is a new step in the approach of using integrated thermoelectric cooling with SMA actuators. In fact, th...