Papers by Author: Carlo Menon

Abstract: Technologies for space applications are often considered to be rather conservative, aimed at ensuring reliability and robustness. Nevertheless, novel concepts coming from research activities have been and are always the lymph for the development of successful and competitive new solutions. This paper presents new concepts and ideas inspired by natural systems with distributed actuation embedded in their structure, considered as ideal models for possible uses in space applications. Preliminary concepts for possible technical solutions for long-term future implementations are here proposed and briefly analyzed. Peristaltic-like actuations obtained by the use of dielectric elastomer actuators is proposed as one of the most promising solutions. Experimental performances of a single actuation unit are here presented and directions for future implementations are proposed.

Abstract: Most animals and insects use opposing muscles, called flexors and extensors, to articulate the joints of their limbs. However, some spiders do not have extensors in some of their joints and use, instead, a simple and efficient miniaturized hydraulic system to extend their limbs. An actuator inspired by the hydraulic system of spiders, which can be embedded on adaptive structures, is investigated in robot-like configurations in this paper. Its design and characteristics are discussed and the effects of the geometrical parameters on its performance are investigated.

Abstract: We present a new concept for compact, tunable antennas. Traditional approaches have circuits and switchable elements which can be bulky and lossy. Here we investigate structures which offer direct tuning through voltage-controlled deformation of the radiating structure itself. The antenna is a dielectric resonator (DRA), where the antenna impedance and tuning depends on the shape of the dielectric. The deformation action is through using electro-active polymer (EAP) for the dielectric. EAPs have promising properties for smart antennas and ongoing developments are continuing to improve its suitability.

Abstract: Since early this decade, investigations into how geckos achieve their remarkable adhesive properties, have determined that multi-scale compliant systems can allow geckos to attach to nearly any surface through Van der Waals forces. Microscopic hairs on the bottom of gecko feet can make intimate contact over large areas, and allows relatively weak Van der Waals forces to produce significant adhesion on the macroscale. Over the past five years, microfabrication technology has been used to replicate these multi-scale compliant mechanisms, using silicon or polymers to reproduce microscale rods or cantilevers to produce what is known as a dry adhesive. What is more difficult is creating the nanoscale compliant systems that create most contact areas in gecko feet. This work examines how a well known problem in reactive ion etching processes, RIE "grass" can be used to great effect to alter surface morphology on the nanoscale for nearly any polymer. Identical etching parameters in the presence of different elements, like gold or aluminum, can result in radically different surface morphologies and material behaviors, potentially allowing both adhesive and non-adhesive areas to be formed in a single material. This technique is potentially the easiest and fastest way to produce nano-compliant systems for use with dry adhesives.