對於任何一種自走車而言，自動避開障礙物的功能是一項重要指標。這項指標應當被設計加入到車子的導航控制系統中，可從對環境的感知，路徑規劃以及車子的控制這幾方面下手進行整合。有時候就算已經知道了障礙物的位置，但是如何在高速下進行避障仍然十分挑戰性，尤其是在即時地進行這些避障的規劃和車子的控制上。
這篇論文當中，有設定了兩個小目標，第一個是盡可能快速地跑完所給定的路徑。第二個則是自動避障，無論是否已經事先知曉障礙物的位置，自走車都必須被要求有能力自發地避開障礙物。
對於第一個小目標，設計了一個自動可調式的速度以及前瞻距離的單純追蹤控制器來達成用越短的時間完成路徑。至於第二個小目標，設計了使用單純追蹤控制器來追蹤所計算出的避障路徑。
最後，將兩者整合起來，這樣就不但可以快速跑完路徑，同時也可以進行避障的動作。雙重模式是一個可以用來實現目標的非常好的選擇，這雙重模式就是巡航模式以及避障模式。

For any autonomous vehicle, the capability of obstacle avoiding is an important feature to be incorporated into vehicle navigation systems through the integration of appropriate sensing, trajectory planning and control system. Even when obstacles’ locations are known, high-speed obstacle avoidance presents challenges in real-time motion planning and control.
In this thesis, there are two sub-goals, one is finishing the given track as soon as possible. While another one is obstacle avoidance, regardless foreknow the location of obstacles, the car is demanded to avoid the obstacles ahead automatically.
For the first sub-goal, Variable Speed and Lookahead Pure Pursuit Tracking Controller is developed to accomplish a shorter runtime with a given track. For the second sub-goal, obstacle avoidance path is designed to be tracked with pure pursuit tracking controller.
Finally, an integration of two tasks on achieving both the trajectory tracking and obstacle avoidance simultaneously has been presented. A dual mode is a good option for realizing the main goal, they are known as cruise mode and avoid mode.

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