进行登月探测之前，在地面采用实验模拟和数值模拟的方法预测和评价月球漫游车通过性能是其开发过程中的必要环节之一；研究月球漫游车车轮驱动力矩的自动控制策略是实现其无人驾驶行驶的重要研究内容。本文根据车辆地面力学的相关理论，分析了月球漫游车车轮-模拟月壤相互作用的力学特性模型以及模拟月壤力学特性参数的识别方法，并对车轮滑转沉陷的形成原因、计算方法和车轮重复通过的力学特性做了较为深入的分析。采用贝氏仪、直剪仪分别进行了模拟月壤的承压实验和剪切实验，基于实验测量结果和Bekker土壤承压模型、Janosi土壤剪切模型，分别计算了模拟月壤的承压力学特性参数n、k和剪切力学特性参数c、φ、K；针对一种月球漫游车的刚性车轮和模拟月壤，在土槽中进行了一系列滑转率下的单轮滚动实验，基于实验测量结果和轮-壤相互作用的半经验力学模型识别了模拟月壤的承压及剪切力学特性参数。将基于单轮滚动实验识别的参数与应用直剪仪、贝氏仪实验测量得到的参数进行了比较分析，二者差别较大，造成这种差别的主要原因是两种实验方法中的模拟月壤力学边界条件相差较大。根据单轮滚动实验识别的模拟月壤力学特性参数和轮-壤半经验力学模型计算了不同滑转率下车轮首次、第二次及第三次通过的沉陷量、挂钩牵引力和驱动效率，其中沉陷量和挂钩牵引力的计算结果与实验测量值吻合很好，验证了轮-壤相互作用力学模型的合理性。进一步应用车轮三次通过的挂钩牵引力和驱动效率的计算结果，分析了三轴月球漫游车的前轮、中轮和后轮的通过性能指标，得知中轮和后轮的最佳驱动效率和最大牵引系数大于前轮的相应值，它们对应的滑转率小于前轮的相应结果。根据相关的通过性指标，首先分析了1/2月球漫游车车轮驱动力矩优化控制模型的目标函数和约束条件，利用ADAMS软件建立了1/2月球漫游车的动力学模型，利用Matlab中的Simulink工具箱建立了优化控制模型，将二者进行联合仿真分析，仿真结果表明了控制策略的有效性。在此基础上，分析了月球漫游车整车的车轮驱动力矩控制策略，并对整车进行了相应的运动学建模。
Before the lunar rover play a role on the moon, its trafficability should be estimated with experimental or simulating method on the earth. And study on torque-control strategy of its wheels is one of the key tasks for autonomous moving on the moon.In this paper, the characteristic of wheel-soil interaction model and the methods of identifying the mechanical property parameters of soil are discussed based on the terra-mechanics. Furthermore, the cause of slip-sinkage of wheel and the wheel-soil interaction mechanical characteristics during multi-pass are analyzed.Firstly, experiments for the lunar soil simulant being compressed and shearing are performed by using bevameter and direct shear apparatus. With the experimental results and BEKKER and JANOSI model of soil, the mechanical property parameters of lunar soil simulant, k, n, c, φ and K are calculated. Secondly, a series of tests for a wheel of lunar rover rolling in lunar soil simulant at different slips are completed. And then, the parameters are identified again with the semi-empirical wheel-soil interaction model and the test results. By compared the parameters gained by the two means, a large difference was discovered between them, which is mainly caused by the different boundary condition of lunar soil simulant in the two kinds of experiments.Based on the parameters identified by the latter method and the wheel-soil interaction model, sinkage, drawbar pull and tractive efficiency of the wheel during the first, second and third pass at the same slip and vertical load are computed. And the computational sinkage and drawbar pull are accord with the test results, which shows that the wheel-soil interaction model is acceptable. Accordingly, the tractive coefficient and efficiency of the front, middle and rear wheel of a three-axle lunar rover are calculated by using this interaction model. Apparently, the tractive characteristics of the middle and rear wheel is better than the front one.According as the tractive characteristics of the wheels, objective function and constraints of a torque-control optimization model for the wheels of half lunar rover are formulated. And then，a dynamic model of the half lunar rover is formed with ADAMS and the optimization model is programmed with SIMULINK. By combining the two model, simulation can be performed, and the results of it demonstrate the validity of the optimization model. Consequently, torque-control strategy for the wheel of the whole lunar rover is discussed.
