渐开线齿面串联弹性器件传动机理研究  

Transmission Mechanism of Involute Tooth Surface Series Elastic Device

作　　者：蒋建东[1] 李明贵[1] 乔欣[1] JIANG Jiandong;LI Minggui;QIAO Xin(Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology,Ministry of Education,Zhejiang University of Technology,Hangzhou 310023,China)

机构地区：[1]浙江工业大学特种装备制造与先进加工技术教育部重点实验室,杭州310023

出　　处：《农业机械学报》2023年第1期425-431,458,共8页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(51375456)。

摘　　要：串联弹性器件广泛应用于外骨骼机器人驱动关节,有利于重载荷情况下的电机软启动。针对旋转类串联弹性器件转动刚度变化引起的传动力矩波动,弹性传动和刚性传动两种状态转换时的传动冲击等问题,提出了一种渐开线齿面弹性器件,建立了传动力学模型,并对器件的弹性-刚性传动过程进行了动力学分析与仿真,研究轴心装配偏差对渐开线齿面啮合滑动率与接触面接合冲击的影响,通过对弹性器件安装倾角参数优化保证了传动件转动刚度变化率最小,有效控制了弹性传动过程中的转矩波动。最后对器件进行了下肢外骨骼驱动关节工程验证和传动静特性实验,结果表明,轴心装配偏差会导致接触面接合时转矩激增,当偏差在0.05 mm内时(渐开线齿面啮合滑动率最大为0.006 5),与平面矩形弹性器件相比,转矩激增值平均降低43.55%。Series elastic devices are widely used in driving joints of exoskeleton robots, because they are conducive to the soft start of motors under heavy loads. Aiming at the problems of the transmission torque fluctuation caused by the change of the rotation stiffness of the rotating series elastic device, and the transmission shock during the transition between the elastic transmission and the rigid transmission, an involute tooth surface elastic device was proposed. Firstly, the characteristic that the involute tooth profile transmission would not change due to the deviation of the axis center can make a smooth transition when the elastic-rigid transmission was converted. Secondly, the transmission dynamics model of the involute tooth surface elastic device was established, and the elastic-rigid transmission process of the device was mechanically analyzed. By optimizing the installation inclination angle parameters of the elastic device, the minimum change rate of the rotational stiffness of the transmission part was 0.117 57, and torque fluctuation in the elastic transmission process was effectively controlled. Then, under the optimal installation inclination angle(π/4±1.337 85 rad) model, the dynamic simulation of the transmission process and the mesh process finite element simulation were carried out to analyze the effect of the axis assembly deviation on the sliding rate of the involute tooth mesh and the contact surface joint impact. Finally, the device was verified by the lower limb exoskeleton drive joint engineering verification and the transmission static characteristics test. The results showed that the axis deviation would cause the torque to increase sharply when the contact surface was engaged. Compared with the flat rectangular elastic device, the torque excitation value was reduced by 43.55% on average when the axis deviation was within 0.05 mm(the maximum involute tooth surface meshing sliding ratio was 0.006 5).

关 键 词：外骨骼机器人 串联弹性驱动器 柔性关节 渐开线齿廓 

分 类 号：TP215[自动化与计算机技术—检测技术与自动化装置]