The term robot comes from the Czech word “robota”, generally translated as “forced labor.” This describes the majority of robots fairly well. Most robots in the world are designed for heavy, repetitive manufacturing work. They handle tasks that are difficult, dangerous or boring to human beings.
The most common manufacturing robot is the robotic arm. A typical robotic arm is made up of seven metal segments, joined by six joints. The computer controls the robot by rotating individual step motors connected to each joint (some larger arms use hydraulics or pneumatics). Unlike ordinary motors, step motors move in exact increments. This allows the computer to move the arm very precisely, repeating exactly the same movement over and over again. The robot uses motion sensors to make sure it moves just the right amount.
Since robot arm technology began to evolve, robotic arms have been successfully used in the automotive manufacturing industry in the 1980s and were the most widely used automated mechanical devices in the field of robotics, while many industrial hazardous assemblies, painting, welding, high temperature Forging and other heavy work, are able to replace the manual arm to homework.
At present, robotic arms are the most widely used automated mechanical devices in the field of robotics. They are found mainly in industrial manufacturing, commercial agriculture, medical rescue, entertainment services, military preservation and even in space exploration Application device.
source from : https://science.howstuffworks.com