基于超磁致伸缩材料的谐波驱动器结构与磁场优化设计

基于超磁致伸缩材料(giant magnetostrictive material,GMM)正逆耦合效应以及能量转换特性,提出一种集驱动、传动及传感于一体的新型自感知谐波驱动器构想.利用ANSYS分析谐波减速器运行过程中波发生器应力分布情况,结合波发生器尺寸结构求解GMM棒的尺寸参数.基于毕奥萨伐尔定律推导驱动线圈内部磁场求解方法并设计驱动磁场和偏置磁场布置方式.利用COMSOL Multiphysics建立驱动器电磁机三场耦合模型,分析在不同条件下驱动线圈内部磁场分布情况以及驱动器的位移输出特性.结果表明:在永磁体总长度不变情况下,对永磁体实行内置均匀布置,随着永磁体片数逐渐增加,磁场均匀度从44％降低到26％,输出最大位移从0.123 mm下降到0.114 mm,GMM棒应力分布均匀度显著提高.

Optimization of structure and magnetic field of a harmonic actuatorbased on giant magnetostrictive material

Based on the positive and inverse coupling magnetostrictive effects and energy conversion characteristics of giant magnetostrictive material (GMM), a new concept of a self-aware harmonic actuator integrating drive, transmission and sensing is proposed. The stress distribution of the wave generator during the running of the actuator is analyzed with ANSYS, and the size parameters of the GMM rod are calculated with the dimensional structure of the wave generator taken into consideration.Based on Biot-Savart law, the internal magnetic field of the drive coil is deduced. Subsequently, the arrangement of driving magnetic field and bias magnetic field is designed. A coupling model of the electrical, magnetic, and mechanical fields of the actuator is built by using COMSOL Multiphysics, with which the distribution of the internal magnetic field and displacement output characteristics under different conditions are analyzed. The results show that with the number of permanent magnets increasing, the uniformity of the magnetic field is reduced from 44% to 26%, the maximum output displacement decreases from 0.123 mm to 0.114 mm, and the GMM rod stress distribution uniformity is significantly improved.