Precision measurement on comprehensive topography of the deep hole surface

摘要

Based on the computer aided test technique, a precision method for measuring the comprehensive topography of the deep hole surface is developed. The measuring principle and data processing method are described in detail. A new built-up function has good linearity and good continuity, therefore it is easy to be subdivided by computer and the error can be corrected conveniently. In order to get a high quality fringe signal, we apply a new correction technique which based on the least square method to correct the A/D values in real-time. Some new methods are firstly employed to predict measuring errors and find the best measuring plan. A serial of experiments are made to verify the method's availability and reliability by using some especial devices and software. Based on the laser holographic diffraction grating, a new experimental instrument is developed to measure the needle valve seat's cone of a diesel engine.