Development Of Non-contact Automatic Measuring System For Engine Crankshaft

With the automotive industry became supporting industry in china, crankshaft domestic manufactories of had implemented automation or partial automation production. But the domestic measuring technique of crankshaft still rests on handwork states that are low efficiency and low precision, and it also becomes a barrier of modern production. Considering factors of price and cost, many domestic manufactories cannot accept the foreign automatic measurement instrument. Domestic manufactories do need the instrument for measuring crankshaft automatically, which suits with level of domestic technology and has independent property right.Aiming to time-consuming, being strenuous, bigger error brought by traditional measurement approach of crankshaft, to improve measuring methods for crankshaft, the non-contact measurement system of engine crankshaft is developed based on CCD. In the system, the image information of crankshaft is collected with CCD and image data acquisition card, and then DIB bitmaps of crankshaft are created. The image processing, edge detection and line fitting algorithm are used for measuring the final outline physical dimensions of the crankshaft. This paper illustrates the working principle and establishment of full system, gives details about mechanical structure and software that is responsible for image processing and result gaining.In order to confirm the system precision, large numbers of experimental was made .The result indicated that this system is completely satisfied to the precision which the crankshaft measurement requests. By use of this system, the crankshaft measurement has made, with the precision of higher than 0.1mm. This system not only reduce the waste in manpower, material and time, but also according to its measurement principle the foundation is established for non-contact measurement of precision shaft.