The welding operation frame is a manual remote control machine, which is operated by a worker's operating handle. Its characteristic is that the structure of the machine can be made very solid and the working range is large. The working condition depends on the worker's proficiency. Robot is a kind of universal automaton with articulated structure (similar to human arm and elbow joint), which can realize the human mechanical function independently (human does not participate in the operation and control). Advanced robots also have vision, hearing and feeling (equipped with various sensors), which can determine their behavior according to the surrounding environment. It is different from human beings in that it has no human brain, only a variety of programs and instructions that are compiled by human beings in advance and play the role of human brain. Because of its articulated part structure, which can simulate human movement, it can not be made very strong and bear limited load

Manipulator is a kind of machinery between manipulator and robot. It has a strong working mechanism like welding manipulator, which can bear a large load, and its control mode is close to robot. Different from robot, operator still plays a direct control role

In the casting workshop, welding operators and manipulators are commonly used. At first, it was only used for handling or sorting castings. Now it has developed to complete cleaning process operations, such as cutting pouring riser, grinding, priming and inspection. The cleaning quality can be significantly improved by using the manipulator and manipulator. For example, when the gas cutting manipulator developed by the Czech Institute of materials science cuts the cast steel riser with a thickness of 400mm and a mass of 500kg, the cutting accuracy is ± 1mm, the cutting surface is smooth, and the finishing work of the remaining riser is reduced or even eliminated. It can improve productivity, for example, the maximum power of the manually operated suspension grinder is not more than 25kW, and the grinding capacity is no more than 5-10kg / h. However, the power of the grinder operated by the manipulator can reach 55kW, and the grinding capacity can reach 100-150kg / h