基於馬達電流量測之行動輔助機器人順應性控制

Abstract

本論文應用全向式移動平台設計了一個行動輔助機器人。行動輔助機器人提供老年人在行動上的輔助，使老年人可以安全且穩定的行動。透過本論文所提出的順應性移動控制器行動輔助機器人會順應著使用者施力方向而移動並根據力的大小調整其速度。本文採用量測全向式移動平台上的馬達電流以及轉速去推算出行動輔助機器人所受的外力大小及方向。透過電腦模擬發現估測器可以得到施力的資訊，並且透過順應性控制器達成行動輔助機器人的順應性移動行為。實驗結果驗證，經由機器人之馬達的電流及轉速回授，可以估測出使用者的施力，並且根據此估測結果完成行動輔助機器人的順應性移動，而經由調整順應性控制器之動態模型參數，則可滿足使用者對行動輔助機器人之順應性的需求。

An omni-directional mobile robot has been designed and constructed to work as a robotic walking helper of elderly people. The robotic walking helper has a handrail to assist the elderly to walk safely and stably. In such application, the motion compliance is required in accordance with the applied force of a user. This thesis presents a novel compliance motion control design for the omni-directional motion platform. In this design, an external force observer is developed based on motor current and speed measurement without using an expensive force/torque sensor. Computer simulations show that the compliance of the omni-directional walking helper can be adjusted by setting damping and stiffness coefficients of the overall dynamical system. Practical experiments validate the simulation results. It is demonstrated that the external force observer successfully estimates the pushing as well as pulling force of a user on the platform handrail. The velocity of the omni-directional walking helper is adjusted according to the inferred motion intention as expected.