Magnetorheological Landing Gear for UAVs – A conceptual design

Thedevelopment of Unmanned Air Vehicles (UAVs) for both military and civilian applicationslead the opportunites for the development of advanced technologies to improve their operational performance. Due to various mission requirements UAVs will carry different types of payloads which change the total all-up weight. The landing gears of the UAVs should be optimized to the changing weights and various sink speeds. Conventional landing gears are optimized for particular set of parameters and not efficient in all conditions. A novel solution to this problem is to implement a smart damping using magnetorheological (MR) fluids. This paper presents a design mtheodology that enable MR landing gear to be optimized, both interms of its damping and magnetic circuit performance using Magnetorheological Grease(MRG). The design approach focuses on the impact of landing phase of an UAV where large variations in the UAV mass, landing speed, sink speed makes MR shock absorber a potential solution. The usage of MRG in the present design overcomes the problem of sedimentation that exists in regular MR fluidswith long term usage.