Design, Analysis and Topology Optimization of a Landing Gear Strut for a Quadcopter Upon Impact

In this paper, a comprehensive approach for design, analysis, and topology optimization for a solid leaf spring landing gear of a quadcopter is presented. Landing gears are a critical structural part of an aircraft that support all up weight in static conditions and absorb kinetic energy in a form of impact loads during touch down. Complete designing along with the analysis of landing gear as per the governing principals and rules have been carried out such that it undertakes static load and impact load of the aerial vehicle having Gross Take-off Weight of 12 kg including the payload capacity of 9 kg. The work includes a comprehensive literature review, mathematical modeling of the strut, calculation of Impact force at static and dynamic conditions. Drop test dynamics has been explained thoroughly which is a prerequisite for experimental verification using drop test of the designed strut before its installation on aerial vehicle. Considering the maximum force encountered during landing, the design of the landing gear along with appropriate thickness has also been undertaken in SOLIDWORKS®. The numerical analysis of the model has been conducted using the continuum approach, considering continuous bodies. Similarly, to validate the proposed design and to determine the structural integrity of strut, finite element analysis has been carried out on landing gear assembly. The deformation, maximum stresses (Von-Mises, Principle Stress) and factor of safety have been computed using SOLIDWORKS®Simulation-Static. Moreover, three materials have been initially used, (Cold Rolled Steel, Al 7075- T6, Al 2024-T3). High strength to weight ration is a critical design consideration for any landing gear strut. The optimization parameter for the analysis is weight of the strut. Hence three optimum variants of the struts have also been proposed with 15%, 35%, 60% reduced weight of each without compromising the strength. The results indicate that the designed strut behaves efficiently meeting all the operational conditions.