Three-dimensional Carbon Fiber Braided Composite Precast Thickness Testing Instrument Developed

The technology of the three-dimensional braided composite materials is a new high-placed textile technique developed in 1980' s. The materials are once braided and its structure is not stratified and it is good in entirety and designed flexibly. So it is closer concerned. It has important relation between composite materials' mechanics and perform thickness and irregularity index, but so far the perform thickness is only measured by hand. Because the measured standard is not unified, the result of measure has great errors. So the materials are not effectively researched and used. From the above, it is essential to design a measuring system, which can measure and analyze its thickness accurately and quickly. It is based on measuring carbon-fiber three-dimension braided composite materials perform, and provides accurately data for analyzing composite materials' mechanics.This paper studies measuring technique of glass-fiber three-dimension braided composite materials perform used by others, specially graduate student CHAI CHUN QIAN' production. So the paper puts forward a measuring method based on bow-wave sensor. Firstly, building measuring system, including bow-wave sensor, press sensor, microcomputer, I/O board, electromotor, machine. Secondly, programming to measuring system included a general program and three thread program, introducing Windows 2000 multithread, using Visual C++ 6. 0. Lastly, designing experiments to gather the data of experiments and analyze the result of experiments. This system proves feasible. Thus the irregularity index is analyzed.The method this paper discussed is an innovatory of the universal thickness measurement. Three research results will help filling in a gap in this field and provide the basis for the study of mechanical capacity and producing the three-dimensional braided composite materials performaccurately.