采样机械臂关节月表环境适应性设计

Environmental adaptive design of joint for a lunar surface sampling arm

文章针对月球表面采样任务对机械臂关节防尘、耐高低温和轻量化的特殊要求,提出一种由永磁同步电机驱动、2K-H行星减速器+谐波减速器传动的关节设计方案。该方案采用电机的齿槽转矩提供关节制动力矩,并采用前馈力矩补偿控制的方法消除齿槽转矩引起的速度波动,节省了制动器的配置;通过控制减速器传动侧隙、电机定子与壳体的过盈量及密封垫片厚度,实现关节在-100~160℃高低温环境的热匹配和防尘。仿真分析和样机试验结果验证了关节设计方案可满足月表采样的月面特殊环境要求。

The sampling robotic arm is one of the important tools to realize the lunar surface sampling, and the joints are the basis of the flexible movement and the precise positioning of the arm. In order to meet the special requirements of the lunar surface sampling task for the dustproof, the high temperature resistance and the light weight of the joint, a joint design scheme of the 2 K-H planetary reducer plus the harmonic reducer driven by the permanent magnet synchronous motor is proposed. In the scheme, the magnetostatic torque of the motor provides the joint braking torque, and the feedforward torque compensation control method is used to eliminate the speed fluctuation caused by the magnetostatic torque and save the brake configuration. By controlling the gearbox transmission backlash, the motor stator shell interference and the gasket thickness, the thermal matching of the joint in the temperature range of-100～160 ℃ and the dustproof goal are achieved. The simulation analysis and the prototype test verify that the joint design can meet the task requirements for the lunar sampling.