摘要
为评估月球车的起动能力,建立了刚性车轮与松软月壤间的轮-地作用模型和车轮驱动电机的有限元模型.应用车辆地面力学理论分析了月球车载荷、车轮半径、车轮宽度、轮刺高度及月壤剪切特性参数的变化对起动初始时刻车轮所受阻碍转矩的影响.分析结果表明,减轻载荷和减小车轮尺寸能够降低起动难度,而月面不同位置下月壤参数的差异可能导致起动难度悬殊.计及月面昼夜巨大温差对磁钢磁性能和绕组电阻的影响,仿真了恒定母线电流下电机的电磁转矩,并结合气隙磁场分布分析了转矩脉动的原因,设计制作了一台样机,样机实验结果与仿真结果基本吻合.仿真结果表明,电机的起动性能对温度变化极其敏感.低温环境下,电机不仅可以获得较大的驱动电流,而且相同电流下输出转矩能力更强.因此,合理设计车轮、慎重选择停车位置和起动时间有助于月球车的起动.
A wheelterrain interaction model between rigid wheel and lunar regolith and a finite ele ment model of wheel driving motor are built to evaluate the starting capacity of lunar rover. The in fluences of load, wheel radius, wheel width, wheel lug height and shear characteristic parameters of lunar regolith on the impeditive torque acting on the wheel flange at the initial time of a startup are analyzed based on the terramechanics theory. The analysis results show that reducing load and wheel measurements can reduce the impeditive torque and the startup difficulties obviously vary at different positions of the lunar surface due to the regolith parameter differences. The electromagnetic torque of the motor with the constant bus current is simulated in consideration of the temperature sensitivities of magnetic property of permanent magnet and electric resistance of stator windings. The causes of torque ripple are studied based on the airgap magnetic field. A prototype motor is designed and manufactured. The experimental results of the prototype are basically consistent with those of the fi nite element simulation. The simulation results show that the starting performance of the motor is greatly affected by the ambient temperature. High driving current can be obtained and high torque can be output with the identical current at low temperature. So, designing rover wheel reasonably and choosing parking position and start time meticulously favor lunar rover＇s startup.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2012年第A01期196-202,共7页
Journal of Southeast University：Natural Science Edition
基金
陕西省自然科学基金资助项目(2011GZ013)
关键词
月球车
起动
轮-地作用模型
车轮驱动电机
lunar rover
startup
wheel-terrain interaction model
wheel driving motor
