Research On The Steering Mechanism Of Manned Lunar Rover Vehicle

Manned lunar landing is the inevitable way for the development of China’s spaceindustry, the manned lunar rover vehicle (LRV) is the essential tool for moonexploration. The steering mechanism is one key part of LRV mobile systems, itsperformance directly affects the LRV steering stability and security, so the steeringmechanism’s design to meet the performance requirements of LRV is significant tomanned lunar landing. On this background, the steering mechanism is designed in thispaper based on Ackerman-geometry steering.The steering mainly includes two ways, differential steering and track steering. Inthis paper the two ways’ characteristics are analyzed and compared to determine whichway to adopt; Ackerman-geometry steering and double Ackerman-geometry steeringcharacteristics are analyzed in this paper, the double Ackerman-geometry steeringadvantages are stated and it is found more suited to adopt; Based on the overall schemeof energy system of the nickel cadmium battery and double wishbone type independentsuspension, the divided steering mechanism is determined to adopt. three kinds ofschemes are designed and carried on the contrast analysis, finally the scheme three isdetermined to adopt as the manned lunar rover steering mechanism.When designing divided steering mechanism, the first problem is to determinesplitting point location. So-called splitting point in structure refers to the connected balljoint center between the tie rod and the central steering link, the center is wheel beatingand folding point of axis of rotation. There are two initial methods for the steeringmechanism splitting point position to determine, graphical method and analyticalmethod. By comparison, one method is better to be used; The inflection circle theoryand Euler-Sawari equation in mechanism subject is used to solve splitting point positioninitially, thus a feasibility analysis is conducted in the process of a wide range of folding.By optimal design, the splitting point position is determined finally.Based on Ackerman-geometry steering theory, the inner and outer wheel turningangles mathematical model is deduced,and the nature of the theoretical model isanalyzed; the optimized mathematical model of the steering mechanism is established.By model optimization and results analysis, the best steering mechanism parameters areobtained in this paper.By using optimized results, the steering mechanism’s Pro/E three-dimensionalmodel and ADAMS simulation model are established; The kinematics simulation of thesteering pull rod folding and the wheel turning angles are carried out to validateprevious reduction rationality. Steering motor and the reducer are selected, according tothe resistance torque and the drive torque, key parts’ dynamics simulation is carried out;By using finite element analysis software, stress condition of key bars of the steering mechanism is analyzed and the steering mechanism’s design work is improved lastly.