基于超磁致伸缩材料的快速制动执行器的设计

摘要

To effectively solve the contradiction between the quick movement and high-precision positioning of braking actuator, giant magnetostrictive actuator ( GMA) is adopted to operate braking mechanism for increasing the response speed of brake system. The overall scheme and the component structure of speedy braking actuator are designed based on the analysis on the design requirements of speedy brake and the principle and feasibility of its ac-tuator. According to the desired actuator displacement and braking force, the calculation method for the length and diameter of GMM bar is given. The relationship between actuator output displacement and the product of solenoid coil turns and excitation current is established by piezomagnetic equation combined with the requirements of speedy braking, avoiding the difficulty of direct calculation of excitation magnetic field intensity. In addition, the basis for selecting coil turns and excitation current is discussed and the calculation formulae for the sizes of displacement mag-nification mechanism are derived. Finally a verification test is conducted with a result indicating that the characteris-tics of B-GMA meet the requirements of speedy braking.%为有效解决制动执行器快速运动和高精度定位的矛盾，采用超磁致伸缩执行器来操纵制动机构，以提高制动系统的响应速度。在分析快速制动器的设计要求及其执行器的原理和可行性的基础上，进行了快速制动执行器总体方案设计和主要部件设计。根据制动所需的位移量和制动力，给出了GMM棒的长度和直径计算方法。由压磁方程结合快速制动要求，建立了螺管线圈的匝数与励磁电流的乘积与执行器输出位移量的关系，避免了直接求解激励磁场强度的困难。与此同时还探讨了线圈匝数和电流选择的依据，推导了位移放大机构尺寸的计算公式。最后进行了实验验证，结果表明B-GMA的工作特性能满足快速制动的要求。