Virtual Impedance Control and Null Space Motion Control for Humanoid Robots
           

- 指導教授 黃漢邦 博士 研究生 侯天祐

- Advisor :Dr.Han-Pang Huang Student : Tian-You Hou

Lab. of Robotics., Department of Mechanical Engineering, National Taiwan University, Taiwan

Abstract:

Virtual impedance control can be used to avoid obstacles, joint limits, and self-collisions. In this thesis, we propose a stabilizer that uses virtual impedance control and maximal output admissible (MOA) sets to guarantee balance stability and execute other functions simultaneously while walking. This stabilizer ensures that the zero moment point (ZMP) does not exceed the constraints by changing the gains of virtual impedance control after computing the MOA sets so that the humanoid robot will not fall.

Furthermore, we use the gradient projection method to control the motion of the humanoid robot in the null space of virtual impedance control. This enables us to execute subtasks while the main tasks are completed through different cost functions.





中文摘要:


虛擬阻抗控制可以用於避障、避免自身關節角度超過最大限制以及防止自身碰撞等方面。本文結合虛擬阻抗控制與最大輸出允許集合,提出在虛擬阻抗控制架構下的平衡控制器,使人行機器人在行走時的穩定性獲得保證,同時能夠達成避障及防碰撞的功能。這種控制器透過計算最大輸出允許集合,適時改變虛擬阻抗控制的控制係數,使腳底的ZMP在行走過程中不會超出限制範圍,因而保證人形機器人不會跌倒。

另外,本文也使用梯度投影法,在虛擬阻抗控制的零空間內對有多餘自由度的人形機器人進行動作控制,透過不同成本函數使得人形機器人能夠在達成主要任務的前提下,同時滿足次要任務的需求。