倾转旋翼机齿轮-丝杠作动器动力学建模及响应分析

Dynamics Modeling and Response Analysis of Gear-screw Actuators of Tiltrotor Aircrafts

倾转旋翼机的倾转机构是由齿轮副与滚珠丝杠副组成的复杂结构,动力学问题较为突出。为准确分析其动态行为并探明振动机制,考虑丝杠副的滚珠冲击激励以及齿轮副的准静态传动误差激励耦合作用,提出了一种齿轮-滚珠丝杠作动器系统动力学耦合建模方法。基于系统动力学方程求解特征值问题,得到了系统各阶固有频率与振型;对比有限元模态分析结果,验证了理论模型的准确性;在此基础上,分析了齿轮-滚珠丝杠作动器系统的动态行为,研究了丝杠副结构参数对输出响应的影响。结果表明,丝杠轴向振动响应随着螺旋升角的增大而减小,随着接触角的增大呈现先增大后减小的趋势。

The tilting mechanism of a tiltrotor aircraft is a complex structure comprised of gear pairs and ball screw pairs,with its dynamic challenges being particularly prominent.To precisely analyze its dynamic behavior and uncover the vibration mechanism,a dynamic coupling modeling method for a gear-ball screw actuator system was proposed.In this method,the impact excitation from the ball screw pair and the quasi-static transmission errors from the gear pair were considered.By solving the eigenvalue problem based on the system's dynamic equations,the natural frequencies and modes were determined.A comparison with the finite element modal analysis results confirmed the accuracy of the theoretical model.On this basis,an analysis of the dynamic behavior of the gear-ball screw actuator system was conducted,along with an exploration of the influence of structural parameters of the ball screw pairs on the output response.The results show that the axial vibration response of the ball screw decreases with an increase in the helix angle,while it follows a trend of initial increase followed by decrease with an increase in the contact angle.