Control Design of flexible link robots with smart materials

随着控制理论和相关领域技术的巨大发展，机器人系统在人们的日常生活和许多军事领域发挥着越来越重要的作用。轻量化柔性连杆机器人需要更少的能量消耗来进行高速作业，这使得它在许多应用中比传统的刚性连杆机器人更可行，例如核场所，地下废物堆积场，深海和太空应用。这些优点极大地推动了柔性机器人建模与控制的研究。为刚性连杆机械臂所建立的控制方法在理论上已不再适用于柔性连杆机械臂。为了进一步提高柔性机器人的性能，必须研究复杂的控制策略。这些原因促使人们对柔性连杆机器人的控制器设计进行了不断的研究。本项目还旨在研究智能材料机器人，即嵌入压电材料的柔性连杆机器人，从而有效消除柔性连杆的残余挠度。由于压电材料可以沿梁建立，并且具有优异的机电性能，可以实现机械变形和电场之间的转换，因此可以作为机械变形的分布式致动器和传感器。因此，压电材料可以形成一种“智能结构”，即由高度分布的致动器、传感器和处理器组成的网络结构。随着智能材料的应用，更容易获得更好的控制性能。这就是我们考虑柔性连杆机器人智能材料控制问题的动机。

With the great development of control theory and technologies in related areas, robotic systems play an increasingly important role in people's ordinary life and in many military areas. Light-weight flexible-link robot requires less power consumption for high speed operations, which makes it more feasible than the conventional rigid-link robots in many applications, such as nuclear sites, underground waste deposit, deep sea and space applications. These advantages greatly motivate the research in modelling and control of flexible robots. The approaches established for control of rigid-link manipulators are theoretically no longer applicable to flexible ones. Complicated control strategies have had to be investigated to further improve the performance of flexible robots. These reasons have motivated continuous research efforts on the controller design for flexible link robot.This project also aims to study smart materials robot, namely a flexible link robot embedded with piezoelectric materials, such that the residual deflections of a flexible link can be effectively eliminated. Since piezoelectric materials can be founded along a beam and have excellent electromechanical property to achieve the transformation between the mechanical deformation and electrical field, they are ready to serve as distributed actuators and sensors of mechanical deformations. Therefore, a kind of "smart structures", i.e., a structure with networks of highly distributed actuators, sensors and processors can be formed by piezoelectric materials. With application of smart materials, better control performance is expected to be obtained easily. This is our motivation for considering the control problem of flexible link robots by means of smart materials.