Bionic Design Of The Wheel For Planetary Exploration Rovers Inspired By Arachnoidiscus Structure And Study On Its Mechanical Performance

Throughout the long period of evolution,creatures have formed the novel biomaterial and lightweight structure featured with excellent mechanical properties,providing great inspiration for human to solve many scientific and technological problems.Diatom frustule,the phytoplankton in vast waters is a typical biological structure of lightweight and high-strength characterized by light weight,high strength,and good pressure-bearing performance,which has always attracted many scholars to use it as a bionic template for lightweight engineering structure.The current wheel structure of deep space exploration vehicles still needs to be further improved in terms of load bearing,cushioning performance and light weight.Therefore,it is of great research significance and application value to apply the bionic innovation idea to design the wheel with light weight,strong bearing capacity and good cushioning performance.Within the limitations of the study,the main work of this paper includes:(1)A new rigid wheel of the exploration rovers inspired by Arachnoidiscus diatom shell is carried out in combination with the force of the wheels.Compared with the traditional spoke wheel,the weight of proposed wheel is reduced by 30.4% under the similar stress.Additionally,the response surface analysis(RSA)is applied to optimize the bionic rigid wheel structure for the optimum design.(2)In order to improve the cushioning performance of the exploration rovers,three different wheel structures are proposed.Finite element method is used to study the pressure performance of flexible wheels,and the effects of different spoke size parameters on wheel mass,stress,deformation,radial stiffness and vertical stability are analyzed.The SW-2d flexible wheel is selected as the optimum design.(3)The motion simulation models of bionic rigid wheels and SW-2d flexible wheels are established in the finite element method.The dynamics analysis of the wheel driving process on flat,convex and gully roads is conducted so as to investigate the ride performance and the cushioning performance of the wheels under different loads,road bump heights and gully widths.(4)The modal characteristics of the bionic rigid wheel and the SW-2d flexible wheel under free condition and prestressed ground constraints are calculated to obtain the natural frequencies and mode shapes in different states.Additionally,the Bekker semi-empirical method is used to study the traction trafficability of SW-2d flexible wheels on the lunar surface.The calculations have found that the movement of the flexible wheel is feasible.