農用無人自走車直行系統之研究

Study on Linear Movement of an Automatic Vehicle in Agriculture

黃雅賢(Yea-Shyan Hwang) ； 李春壽(Chuen-Show Lee) ； 盛中德(Chung-Teh Sheng) ； 盧世昌(Shyh-Chang Lu)

《農業機械學刊》 6卷4期 (1997/12) Pp. 61-68

https://doi.org/10.30062/JAM.199712.0006

摘要

農業上有許多作業須朝自動化甚至無人化發展之必要性，但其中以施藥作業無人化發展最具迫切性。雖工業界已發展出許多無人自走感測與控制技術，利用超音波感測器感測外在環境所衍生出的系統最適用於農業，本研究即利用超音波感測器感測自走車與植株的距離，並依作業的特性發展行走控制系統，控制自走車的行走，使自走車在兩植行中間行走，不會撞及植株。以單晶片8051微電腦為控制中樞，利用線性位置轉換尺與車輪偏向角同步動作的方式掌握車體的方向。單晶片8051每225微秒自感測器取樣一次，並立即依以所得訊號做行走狀況判斷，若有偏差則依需要作修正。由實驗得知，自走車之行走軌跡受設定之距離差容忍値所影響。植株直徑對行走軌跡左右偏差幅度無影響；設定之左右距離差容忍値越小，行走軌跡偏離幅度也越小。

關鍵字

超音波 ； 自動導引

並列摘要

There are many operations in agriculture, which need develop to be automatic. Especially, the development of automation for chemical application is desperately required by the operators. Although in industry there exist many sensing and controlling units and technologies, which can be applied in an unmanned automatic equipment. The system to utility an ultrasonic sensor to sense and recognize the environment to become automatic has the best potential to use in agriculture. This study is to use an ultrasonic sensor to determine the distance between an automatic vehicle and plants. The travelling controlled unit is developed based on the actual field practice. The vehicle is controlled to travel in the middle of two rows of plant, and does not collide with the plants in the whole operation.
A single chip micro-processor 8051 is adopted to form the central control unit in this study. A linear position transformer is linked to the front wheel shaft in order that the transformer can turn and show the direction of the vehicle in real. The chip 8051 samples data every 225s. The control system analyzes the data and requests the vehicle to make necessary direction adjustment in real time.
From experimental results, the travelling tracks of automatic vehicle are mainly influenced by designed tolerances. The change of diameter of plant does not influence the deviation of tracks significantly. As the designed tolerance is smaller, the deviation of tracks is smaller.

並列關鍵字

Ultrasonic ； Autonomous Guiding