Embedded Control System Of Inspecting Instrument For Steel Ball Surface Defect

Bearings are very important part in mechanical equipment, which are used widely, and they are playing a great part in modern industry. To a large extent, bearing's precision, motility and service life depend on the quality of steel ball in bearing. A great deal of bearing experiments indicated: among bearing failure forms, the ones induced by crack and slit of steel ball surface which result from surface defect of steel ball account for 60%, that is to say, the surface quality of steel ball is one of important factors which are used to judge the performance of bearing, so surface quality of steel ball must be inspected in industry production. At present, the domestic factories for bearing or steel ball mostly adopted manual visual method to inspect surface quality of steel ball. This kind of method is usually affected by many labile factors such as worker's technical ability, emotion, responsibility, tiredness and so on, and it has heavy labor intensity as well as high undetected error rate, furthermore, it is difficult to obtain statistical inspecting data, so the inspect efficiency is very low. In order to inspect and classify effectively surface defects of steel ball, an automatic inspecting instrument is urgently required.Aimed at some problems existed in automatic inspection for steel ball surface defect, we developed the inspecting instrument based on machine vision detection technique, which is applied to detecting external bug area of steel ball. This thesis made some significative exploration in machine of inspecting system, control circuit, drive circuit, real-time character of control system and so on, and researched the correlative key technique.This thesis mostly researched the control and drive of automatic inspecting system for steel ball surface defect, adopted DSP chip of TMS320LF2407A as main processor to develop the control circuit board, developed blending step motor driver based on the chip L297/L298, and realized accurate control for motion trace and surface spread of steel ball. In order to simplify the design of application program and improve real-time character of control system, this design transplanted the real-time kernelμC/OS-Ⅱi nto the TMS320LF2407A, and elaborated the code and optimization of transplantation in detail. According to the work circumstance of steel ball inspection, the control program was divided to corresponding multitask programs and these programs were developed respectively, so the whole embedded control system was established. The result of experiment and simulation indicated that the design of control system is proper, and the embedded control system for inspecting instrument has high control accuracy and excellent performance, which can satisfy adequately the requirement of high speed and real-time image detection.