Imagine visting a farm and realizing that the farm itself only covers a couple of acres. You ask the farmer about it, and he replies that he simply doesn't have enough manpower to work a larger amount of land. He is the only man working the farm, and he doesn't have any tools or animals. He has to work the whole farm by himself, by hand.
Now imagine going to a farm and not seeing any person working the fields. You go inside the house, and notice that the farmer is sitting in front of a computer still in his pajamas. You ask what he is doing, and to your surprise, he answers, “farming.” He is controlling all the robots that are doing the actual farming for him with the use of a high-tech computer program. The robots can irrigate, plant, weed, harvest, package and label the crops without any help from the farmer other than through his use of the computer program. The world is not at this point yet, but in recent years we have come closer to achieving this goal.
To understand agricultural robotics, we need to understand the definition of a robot. A robot is defined as a machine created out of mechanical parts. 
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