A product structure model based on the assembly topology tree is put forward. Based on this, the object-oriented product model classes are built up. By using tabular layouts of article characteristics technique, the transformation from part classes to part examples is realized, so the variant design of product can be carried out. Associated with variant rules and tabular layouts of article characteristics technique, aircraft tooling’s fast design system on the CATIA V5 software platform is used in a large aviation enterprise. And a case illustrating practicability of product variant design is verified.
It is described how to use acoustic emission （AE） technology for aviation aluminum alloy high￣speed milling process monitoring. A monitoring device hardware systems and the composition of signal data acquisition platform are introduced. The signals are decomposed by using the wavelet analysis, and then each frequency band of energy after decomposition is computed. From the comparison of each frequency band of energy, it is found that signal energy can be used as the characteristic parameter of the tool wear.
The computer-aided aircraft design is mainly realized in aircraft manufacturing enterprises, but the aircraft product tolerance design still depends on calculation by hand. A method to construct a national standard tolerance, fitting and aircraft construction tolerance database by using VC++ and Access is put forward in order to realize automatic lookup of tolerance and fitting. With the help of this automatic lookup program, engineers can design or verify tolerances conveniently, quickly and precisely. This method provides a basic technique to realize the computerization of aircraft constructuion tolerance design.
