In the early days, the development and manufacturing of industrial products were generally implemented through product design, module design, part processing, assembly and checkout for productions. This process was called forward engineering (FE) 1. Nowadays, most researching and applications involving reverse engineering focus on geometrical shape, that is reconstructing product’s CAD model and finally manufacturing the product. This is called reverse engineering (RE) 2. Reverse engineering’s application in other fields is also based on measuring data or practical object, and constructing a three-dimensional geometrical model. Therefore, as the precondition of reconstructing a three-dimensional model, figure surface digitalization, that is obtaining adequate data from an object to describe it, is one of the most important processes of reverse engineering. Thus, a researching on measuring and obtaining three-dimensional data from a part’s surface plays an important role in reverse engineering.
According to contacting or non-contacting the surface, the methods of sampling a three-dimensional surface data can be divided into two kinds, contact measurement and non-contact measurement. Contact measurement was generally applied in traditional coordinate measuring machines (CMM), with many disadvantages such as the slower measuring, easily scratching the surface, existing contacting pressure and radius compensation.
Non-contact measurement includes laser triangle measurement, laser distance measurement, optical interference, structural optics, image analysis and so on 3. Non-contact laser triangle measurement (simply called laser probe measurement below) can effectively avoid the system error and the random error which are triggered by contact pressure in precise measurement. It can measure a soft or thin object fast and effectively. According to the lamp-house, it can divided into three kinds, spot lamp-house, line lamp-house and plane lamp-house.
In this paper, in order to obtain reliable data, spot lamp-house method based on laser triangle measurement was applied to acquire data, the hardware structure and the software system of non-contact laser probe measurement system were introduced and implemented.