新型主-被动悬架式星球车垂直越障性能分析

Vertical Obstacle-climbing Performance Analysis of Novel Planetary Rover with Active-passive Suspension

针对现有星球车移动系统因摩擦系数需求较大而制约其越障能力的问题,提出一种摩擦系数需求较小、越障能力强大的新型主-被动悬架式六轮移动系统构型。该移动系统采用双差动连杆悬架机构连接前后两节的三对车轮,具有被动、半主动和主动三种行驶运动模式。建立星球车的运动学和准静力学模型,对三种模式的垂直越障性能进行了分析,获得了实现越障车轮所需的摩擦系数,并以此作为评价指标,对所设计的星球车移动系统和其它典型星球车移动系统的越障性能进行了对比讨论。建立了所设计的星球车移动系统的虚拟样机模型,校验了其半主动和主动模式的垂直越障性能。计算与仿真结果表明,所设计的新型主-被动悬架式星球车半主动模式的垂直越障能力与摇臂-转向架式悬架星球车相当,主动模式的垂直越障能力相较于摇臂-转向架式悬架星球车有显著提升。

To solve the problem that the obstacle-climbing ability of the existing planetary rover is restricted due to the large friction coefficient requirement,a novel active-passive suspension six-wheel mobile system with small friction coefficient requirement and strong obstacle-climbing performance is proposed.The mobile system uses a double differential link suspension mechanism to connect three pairs of wheels in the front and rear sections,and has three motion modes:passive,semi-active and active.The kinematics and quasi-statics models of the rover are established,the vertical obstacle-climbing performance of the three modes is analyzed,and the friction coefficient requirement of the wheels to complete the obstacle-climbing is obtained.Using the friction coefficient requirement as the evaluation index,the obstacle-climbing performance of the designed rover mobile system and typical rover mobile systems are compared and discussed.A virtual prototype model of the designed rover mobile system is established to verify the vertical obstacle-climbing performance of the semi-active and active modes.The calculation and simulation results indicate that the vertical obstacle-climbing performance of the designed rover mobile system in semi-active mode is equivalent to that of the rocker-bogie rover,and the vertical obstacle-climbing performance of the active mode is significantly improved compared with the rocker-bogie rover.