隨著自動化技術的進步，各行業盡可能採用各種機器人代替人類工作力。本文探討差動驅動移動機器人的路徑追踪和避障控制，並實現原型機器人。路徑追踪是移動車輛在標記路徑上向前移動的能力。另一方面，避障行為則確保車輛移動時不會碰到路徑中任何物體。
該原型機器人遵循標記路徑，檢測障礙物並採取必要的行動以避免碰撞。該設計融合了following line 和following wall兩種模式。以三組路線追踪感測器得到的資料經由PID 控制修正路線偏移量，實現追蹤路徑功能，其中，在PID值偏小情形下提升基礎速度( base speed)前進，相較於固定基礎速度條件，於實驗設計路徑上節省11.4%時間。另外，以三組超音波感測器偵測行進路線中障礙物，當測得障礙物時進入following wall模式繞障礙物前進，直到線追踪感測器測得標記路徑再切回following line模式繼續前進。

With the progress of automation technology, the industries are trying to adopt robots instead of human workforce in fields. This thesis discusses control of path tracking and obstacle avoidance for differential drive mobile robot and implements the prototype robot. Path tracking is the ability of the mobile vehicle to move forward on the marking track. Obstacle avoidance behavior ensures that the vehicle doesn’t hit any object in its path while moving.
This prototype robot follows marking track, detects obstacle and take necessary actions to avoid it. The design fused two modes- following line and following wall. The three sets of line tracking sensors and ultrasonic sensors are implemented in this prototype to detect path and obstacles respectively. The data obtained by the three sets of line tracking sensors are used for PID control to correct the deviation from the marking path. Compare to constant base speed scenario, the advantage of variable base speed scenario while PID value is significant small is 11.4% time saving in the route applied in this paper. As for obstacle avoidance, three sets of ultrasonic sensors are implemented to detect obstacles. The robot switches to following wall mode to follow the boundary of obstacle once any one is detected on the path. The robot switches back to follow line mode once the marking path is detected again.

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