仿生蛇型機器人適應於地面環境變動之運動控制

Abstract

蛇類擁有絕佳的地形適應能力。牠們能因應不同的地形去改變運動的姿態，因此在幾乎所有的環境下都能達到極有效率的運動。如此卓越的地形適應移動能力，是仿生蛇型機器人被發展的主要因素。這也使得蛇型機器人在工程領域上有著很廣泛的應用，特別是搜索及探勘這類需要在未知且複雜的空間下移動的任務。 雖然現今已有許多關於蛇型機器人的建模，控制和硬體製作相關的研究，然而針對蛇型機器人地型適應能力的研究卻不多。 在本論文之中，我們由理論上推導出了多連桿輪型蛇型機器人的動態數學模型，並且分析此動態模型在基於蛇行運動下的特性。藉著分析的結果，此動態數學模型可以被近似成一線性模型。以這個線性模型為基礎，我們提出了一個模型參考的適應控制架構。藉此適應控制系統，蛇型機器人的速度及角速度，或是速度及方向，在地面摩擦力變動的情況下，仍然能夠被成功的控制以達到所需要的運動。 最後，藉著幾個不同條件下的模擬結果，在本論文中所提出來的這個適應性控制系統的收斂性及適應性可以被驗証。

Snakes have excellent terrain adaptability. They change their moving postures to adapt to different terrains and can move efficiently in almost all kinds of environments. By the inspiration from snakes, biomimetic snake robots are developed for superior moving capability. Such snake robots are suitable for wide engineering applications, especially for search and exploration tasks. Many researches have been done on modeling, control, and manufacture of snake robots. However, there are few studies devoted to the terrain adaptability of snake robots. In this thesis, a mathematic dynamic model of a multi-link wheeled snake robot is derived and analyzed based on a snake-like locomotion. In the basis of the analysis, the dynamic model is approximated to a linear model. According to the approximate linear model, a model-reference adaptive control architecture is proposed for adaptive motion control of the snake robot. With the control system, the velocity and angular velocity, or velocity and moving direction of the snake robot can be controlled simultaneously with adaptation to variable ground friction. Finally, to examine the convergence and adaptability, the control system is tested in several different cases by numerical simulations, and the results are exhibited and discussed.