Designed Of Control System On Escape Wheel Semiautomatic Visual Inspection Instrument

Automatic detection is an important direction of instrument design. Escape Wheel Semiautomatic Visual Inspection System was designed to detect escape wheels of mechanical watch automatically and accurately, in which the vision detection technology, automatic control technique and precise mechanic design were gathered in a whole. The designed of automatic control system was described in this paper, the research method and main contents include:1. Have designed the overall scheme of control system. The control system is divided into two parts, the 2-D motion control system and the no-motion control system, based on its control characteristics and requirements. By comparing kinds of common movement controllers, motion actuators, control methods, and movement modes, we chose PLC for controller, AC servo motor for actuator, and used half-closed loop control method and point to point movement mode to design the 2-D motion control system. Analyzed the system communication and used free port communication mode between PC and S7-200 PLC. Analyzed the needs of no-motion control system and finally completed the overall scheme design.2. Have completed the hardware design of control system. In this part, we firstly calculated the driving force of the 2-D moving worktable and chose an appropriate motor. Then chose position control mode of AC servo according to the location requirement of the worktable, and designed the circuit connection of PLC and AC servo. Thirdly the method of zero adjustment was proposed by using CCD camera to reference to preset feature point. Finally, the installation and calibration of the worktable were completed.3. Have completed the software design of control system. PLC control programs were designed according to different requirement of different work modes of the worktable, PLC communication program was designed in accordance with communication mode of PC and PLC, the PLC program of fault diagnose and exception protection were designed based on the needs of fault diagnosis of the visual inspection system.4. Have designed the accuracy verification experiment. Used Laser interferometer to test the moving accuracy of the worktable,and verified the total position accuracy through image processing and deviation comparison. The data of the experiment shows that the motion control system can meet the needs of the Visual inspection instrument. The Escape Wheel Visual Inspection System now has applied at industrial field.