Research On Buffer Performance And Semi-Active Control Methods Of The Lander Magnetorheological Fluid Buffer Device

With the development of China’s Chang’E lunar exploration program,designing a good performance of soft landing buffer system is an integral part of the whole task,such as with small volume,high buffer efficiency and good adaptability to the environment.As a representative of the new buffer,buffering force is controllable,buffering effect is good and reusable magnetorheological fluid damper(MRFD)is the research hotspot in this field.This paper is aimed to research on MRFD’s structural design,semi-active control,buffering performance and other aspects,the concrete research contents are as follows:First of all,bypass type of MRFD is chosen as the research target,the damping forces of each region in the case of a magnetic field and a non-magnetic field are calculated.ANSYS is used to simulate the bypass structure size’s influence on buffering force,and a MRFD with the reasonable structure size is designed for the 800 Kg lander.Then,a quarter of the simplified lander model is set up,and the semi-active control strategy for the MRFD is researched.Asynchronous sampling method is used to reflect the rheological response delay of MRF,and control strategy models are built in MATLAB for the simulation contrast analysis of state jump control,multi-state control and fuzzy control.The results show that the control effect of fuzzy control is best.At last,a model of single leg lander is set up in ADAMS,and buffering forces are added to lander as a pair of interaction forces.Different control models are built in MATLAB according to the control strategies,and then are co-simulated.The results show that,MRFD performs well in lander’s buffering control,buffering force can achieve self-regulation,fuzzy control strategy can reduce the large instantaneous overload at the landing moment and during the buffering on hard lunar surface.