运动副间隙对多杆锁机构动力学特性的影响

摘要

To reduce the probability of aircraft cargo door opened accidently caused by abnormal stress, the dynamic characteristics of multi-linkage lock mechanisms with kinematic pairs clearance are studied in detail. The equivalent joint clearance link ( the length is e) is used to describe the influence of kinematic pairs clearance. Meanwhile, the dynamic analysis model of multi-linkage lock mechanisms is built based on the Lagrange kinetic equation and the screw theory, and the procedures programmed by MATLAB are used to solve and analysis the model. Results indicate that the kinematic pairs clearance has a bigger influence on angular velocity of the rod, angular acceleration of the rod, driving moment and hinge binding kinematic, and the greatest influence appears near the singular configuration. While e is 10 μm, its impact on dynamics of the multi-linkage lock mechanisms is small, however while e is 100 μm, the impact is enhanced obviously.%为降低因受力异常而出现飞机货舱门意外打开的概率，详细研究运动副间隙对多杆锁机构动力学特性的影响。采用无质量的等效间隙杆描述运动副的间隙，以拉格朗日动力学方程和螺旋理论为基础建立了多杆锁机构的动力学分析模型，并用MATLAB软件编程对模型进行了求解分析。结果表明：杆的角速度、角加速度、驱动力矩和铰链约束力对运动副间隙的大小比较敏感，在奇异位型附近受到的影响最大。间隙为10μm时，其对多杆锁机构的动力学影响较小；间隙为100μm时，其对多杆锁机构的动力学影响明显增强。