Mechanical arm, as its name implies, is a mechanism designed to imitate the human arm, which is a type of series robot mechanism.
First, we install different executing components on the wrist of the mechanical arm, which can be a series of executing components with different working purposes, such as grippers, drills, welding guns, etc. And then we need to realize the target position and posture of the executing components through the movement of its upper arm and forearm and even the wrist 
The way to realize this is based on the serial robot. We take the parameters between the parts of the robot arm (for example, taking the torsion angle of the connecting rod and the included angle of the connecting rod) to deduce the positions of each part according to the position and the executing components, so as to adjust these parameters and realize the movement.However, in general, there will be multiple solutions in this reverse calculation, which requires optimization and trade-off. The model established by this calculation is to represent the position and attitude of each kinematic pair with the matrix, and the deduction discussed above is to deduce the position and attitude matrix of each kinematic pair of the manipulator according to the position and attitude matrix of the executive component.
As for refinement, it needs to be realized by computer programming and control systems. These are the main principles involved. The types of mechanical arms are also different according to the selection of their coordinate systems, including cylindrical coordinate system, rectangular coordinate system, spherical coordinate system, articulated and planar articulated industrial robots (or mechanical arms). Different coordinate systems have different workspaces and different ways to realize controlcalculation. The principle of articulated manipulator is mentioned in the previous paragraph.
Currently, mechanical arms are quite expensive. Let’s explore the reasons involved.
Because the mechanical arm is not only a commodity, it is also a production tool, similar to the notebook used by programmers. And it can also generate value by itself.
As a production tool, a mechanical arm can generate extra value.
Therefore, there is a premium in itself.
Its own manufacturing involves all aspects of the industrial chain, and all the people in the industrial chain need to earn money to support their families.
The problem of shipments. Everyone may buy a computer, but not everyone will buy a mechanical arm. Output is inversely proportionalto price.
The development of control systems and advanced control algorithms requires a lot of money, and the research and development cost is high.
To sum up, the mechanical arm brings great benefits to our life and work. It has its own advantages in precision and speed, which will be further improved with the rapid development of science and technology. In the future, we will see mechanical arms in various situations, and they will be good helpers in multiple fields, including surgery, manufacturing, etc. We need to have a cautious attitude towards the development of mechanical arms and generate more benefits to the world.
