Development Of Servo Motion Control System Based On The Communication Method Of PROFIBUS-DP

For the dynamic balance of tire, the automaticity and detection accuracy of its testing machine have a great influence on the usability of the tire used in the market. Among all the workstations of a dynamic balance testing machine (DBM), the test station is the core part of the machine. As the most important part of the test station, the stability of the spindle motor plays a decisive role to the accuracy of the test system.Among all the machines used in China, there are two kinds of structures for the spindle motor, they are belt transmission structure and small direct-drive motor structure. However, the belt transmission structure may be affected by the instability of belt, which makes the results of the dynamic unbalance of tire inaccurate. Besides, the small direct-drive motor structure is not reliable, thus also making the data inaccurate.The use and development of frameless direct drive motor serve a new way for the design of the spindle motor structure of the machine. This structure could make the followers move without any transmissions. By using this kind of structure, we could make the rim and the tire on it rotate through the motor, and we can avoid the influence on the test result of the external transmissions.This paper aims at developing a dynamic balance testing machine for mud tire and combines the actual needs of company, and then develops a spindle servo motion control system used in this machine based on the communication method of PROFIBUS-DP. Using the technology of industrial detection, PLC motion control, human-computer interaction and data process, this system could test the dynamic balance of all kinds of tires represented by mud tire accurately and steadily, which strongly improves the development of the technology of dynamic balance test for tire.Because of the use of direct drive motor in the dynamic balance machine, if we want to accomplish the required motions, we also need to design the dedicated encoder, servo driver, PLC and external circuitry. In the aspect of hardware system, this system uses Kollmorgen direct drive motor and S700 servo driver. Mitsubishi Q series PLC plays as the core of control part and the man-machine interactive system uses the Mitsubishi GOT series touch screen. In terms of the software system, besides the development tools of every part, we also need the use of industrial personal computer. The key point of the research on this paper is to make the system finish accurate motion control including constant speed rotation, location and homing with the use of bussing technology. The main difficult points of this research include the stability of communication, the rationality of PLC parameters and program, the rationality of servo parameters and the intelligence of system maintenance.The application in the actual industrial site shows that the development of this motion control system not only solves the problems of inaccurate results that exist in dynamic balance testing machine, but also has better stability, safety and intelligence in recovery processing. This system could also be used in the other industrial automation device, so it has wide prospect in application to industry and it is of strategic importance to the research of high-grade machine manufacturing industries and precision equipment manufacturing industries.