基于相似理论开展月球车轮壤相互作用系统参数量纲分析,分别以模拟月壤内聚力和密度参数不变为约束条件,推导了轮壤系统参数比例尺.采用轻质量模型样车法当量月面低重力环境影响,设计1/2比例月球模型样车;以速度和坡度为试验因素,开展月球车坡面通过性试验;分析了试验因素对各车轮滑转率和沉陷量的影响规律;讨论了不同坡度条件下驱动扭矩、挂钩牵引力和牵引系数随滑转率的变化规律.结果表明,坡度对通过性的影响明显较速度的大;随着滑转率的增加,驱动扭矩和挂钩牵引力呈现增加趋势,最大值分别为3.6N·m和10.5 N;牵引系数呈现先增加后减小趋势,在滑转率为21.6％时达到最大值0.18.为保障月球车安全可靠的通过性能,其巡视坡度在20°以内合理.%Dimensional analysis on parameters of wheel-soil interaction system was performed,and the parameters' scales were also acquired when the density and cohesion of simulant regolith were kept consistent,respectively.The lightweight model method was adopted to eliminate the influence of low gravity environment,and a 1/2 scale lunar rover model was designed.The slope angle and wheel velocity were taken as the experimental factors,the wheel sinkage and slip ratio were taken as the experimental index,test on lunar rover's slope trafficability was carried out,and the experimental factors' influences on the wheel sinkage and slip ratio were analyzed.Variation laws of the driving torque,drawbar pull and traction coefficient with the slip ratio under different slope conditions were analyzed.Results indicated that the influence of slope angle on trafficability was more obvious than that of wheel velocity.With the increase of slip ratio,the driving torque and drawbar pull presented increasing trend,and the maximum values of the driving torque and drawbar pull were up to 3.6 N· m and 10.5 N,respectively.The traction coefficient was increased first and then decreased with the increase of slip ratio,and it was up to its maximum value of 0.18 when the slip ratio was 21.6％.In order to ensure that the lunar rover had safe and reliable trafficability,the exploring slope angle within 20° was reasonable.The research result would provide a reference for the evaluation of lunar rover's slope trafficability under low gravity environment.
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