关键词: 刚柔耦合, 拉格朗日方程, 设计空间, 微小型飞行器, 压电双晶片驱动器

Abstract:

In order to magnify the output angular and torque of piezoelectric bimorph simultaneously, and increase the space utilization of ammunition inside, one new-type scheme of the bullet based post-buckling pre-compression (PBP) piezoelectric bimorph rudder actuator is proposed. The design space of actuator is increased by multi-bimorph stacked, and adjusted by angular magnified connecting rod mechanism, thus the goal of increasing the output angular and torque at the same time is achieved. The statics numerical model of measuring output torque, the rigid-flexible coupling Lagrange dynamic equation of the actuator and their FEM model are founded. By statics analysis, structural strength check, and the transient dynamic analysis, the numerical and FEM results are obtained, which conforms to each other comparatively well. Statics results show that, comparing to original PBP, the output angular and torque of new-type PBP are magnified and the design space is amplified more than 80%. In case of the maximum output torque, strength requirements of each part are achieved. The dynamics results show the transfer and distribution of interior energy of actuator. Taking the rudder with the rotary inertia of 1×10^-2 kg·mm² as the driving object, the control bandwidth reaches 300 Hz, which is much better than those of the ordinary micro-servo-actuator. Therefore, this new-type PBP actuator scheme can provide reference to the development of kinds of micro aerial vehicle (MAV)’s rudder actuators characterized by narrow interior space and high control bandwidth.

Key words: design space, Lagrange equation, micro aerial vehicle (MAV), rigid-flexible coupling, piezoelectric bimorph actuator