Design Of A Gaint Magnetostrictive Hydraulic Pump Actuator And Its Application In Foldable-wing Morphing Aircraft

With the development of aerospace technology, new challenges on the aircraft with the traditional configuration have been proposed all the more. One step after another, global researchers have already started to explore developing new conceptual aircrafts with the structural self-adaption, which may sustain timely aerodynamic performance and flight state via radical shape change of the structural configuration under different missions in multiple flight environments. As a result, morphing aircrafts come up, as the time and technology call for. As one type of morphing aircrafts with large shape deformation, the foldable-wing morphing aircraft needs to be driven from one shape to another in a special and innovative way.Giant Magnetostrictive Material(GMM), a new smart material, has drawn more and more attention of researchers for its remarkable advantages, i.e. large magnetostrictive strain, high output stress level, fast response, and high conversion efficiency of energy. The properties mentioned above have been taken advantage over to develop many new actuators, which have got application in the field of aerospace, precision machining, robotics etc., and met the demand for the equipment of compact bulk, light weight, and convenient control.The properties of GMM could be utilized, with the hydraulic advantages of high power output and system reliability, to develop a new type of GMM hydraulic pump actuator, as the power unit of the hydraulic system. The whole hydraulic system could also be constructed schematically, which will be used as the approach to driving the folding of the aircraft with foldable wings. These are the ideas this paper.In this paper, first of all, the operation principles are presented, and a GMM pump actuator is designed and manufactured under the theoretical guide of the Solid Mechanics, Meterial Science, Electromagnetism, and Mechanical Design Principles. The overall performances of the actuator are tested, and the relations between the output flow rate and the current, frequency, bias of the input electric signal, as well as pre-pressure of the hydraulic system are obtained, respectively, and the relation between the output pressure and those four input parameters above are also obtained, respectively.Secondly, referring to the performance test results and design characteristics of the GMM pump actuator, the specific 3-D structural models of the two types of the foldable-wing aircraft fuselage and the inner and outer wing sections with rocker or screw driving mechanisms are designed and constructed in CATIA individually, and the structural features and configuration are analyzed in general. Besides, the theoretical motion model of the foldable-wing aircraft with the rocker driving mechanism is established, which testifies the DMU kinetic simulation results of CATIA, and vice versa.Finally, the dynamic simulation of the foldable-wing aircraft model under its own weight is conducted based on ADAMS, and the driving force which carries the folding motion is obtained. The hydraulic system layout with the GMM pump actuator being the power source is designed schematically, and the typical test result of the GMM pump performance is chosen to compare with the dynamic simulation counterpart, which verifies the feasibility of the hydraulic folding-driving system design.