Study On Dynamic Characteristics Of Metal Rubber-Aluminum Honeycomb Lander Buffer Mechanism

Soft landing is an important part of the lunar exploration project.The lander absorbs shock energy through the buffer mechanism to achieve soft landing,so as to effectively protect the precision instruments carried and ensure the smooth progress of subsequent detection tasks.With the continuous development of the lunar exploration field,the subsequent lander will realize the walking function to expand its detection range and improve the detection efficiency,and the shock caused by the walking process will affect the working reliability of the lander,so this dissertation proposes a buffer mechanism scheme that gives consideration to both soft landing and walking buffering,and studies the dynamic characteristics of the lander buffer mechanism.The configuration of the buffer mechanism is analyzed,and the dynamic model of the buffer mechanism during the soft landing process is established.Combined with configuration analysis,the simulation model of soft landing is built.The energy absorption mechanism of metal rubber and aluminum honeycomb is analyzed to establish the buffer force in ADAMS.Taking metal rubber and aluminum honeycomb as research objects,the simulation of soft landing with different cushioning medium is carried out,and the matrix centroid acceleration and displacement are compared and analyzed.The optimal solution of metal rubber and aluminum honeycomb as buffer medium is determined.Based on the above study,the configuration of the buffer is given and the dynamic model of the buffer is established.It provides theoretical support for soft landing simulation study and performance analysis.The soft landing process simulation under different conditions is carried out through the soft landing dynamics simulation model of the lander.From the aspects of matrix centroid acceleration,maximum energy absorption ratio,landing stability and other aspects,the effects of changes in operating parameters such as horizontal speed,lunar soil friction coefficient,lunar slope on the soft landing buffer effect are discussed.Based on the simulation results,a comprehensive evaluation index is established to evaluate the cushioning effect,and the metal rubber cushioning stroke and aluminum honeycomb collapse force are optimized based on the gradient descent method to improve the soft landing stability.The shock resistance of metal rubber cushioning components is simulated,and the simulation model of metal rubber shock resistance is established by ANSYS LSDYNA.Based on the single-degree-of-freedom simulation model,the system response theory under shock load is studied,and the relationship between the system response under half sinusoidal excitation and the parameters is obtained.The factors affecting the mechanical properties of metal rubber are analyzed,and the effect of temperature and relative density on the nonlinear mechanical properties of metal rubber is studied to define the spring and damping element in the simulation model.Based on this,anti-shock simulation is carried out,parameters such as excitation peak value,excitation pulse width and relative density of metal rubber are changed,and the temperature is compared orthogonally,which provide a basis for the application of metal rubber components in buffering during walking.The walking process of the lander is analyzed,and the finite element simulation model of the lander is established.The semi-sinusoidal load is used to simulate the shock of the walking process.The shock resistance simulation of the lander under walking condition is studied.The effect of the change of the cross-sectional area and length of the metal rubber component on the response of the shock isolation factor and the maximum strain of the component is explored.On this basis,the simulation optimization scheme is determined and the parameters of the metal rubber component are optimized to achieve effective buffering of walking conditions.