| Since more and more structures are becoming larger and more complex than before,there are many new structures in modern time. At the same time,there are various damage in many existed structures,and they have been used for several decades and are to be surveyed and strengthened. When they are being diagnosed and strengthened,there is the first problem that how the sensor are disposed and how many sensors are disposed in structures. This paper discusses the development of sensor placement. It focuses on the sensors placement of space grid structures,and chooses three types of space grid structures as calculating model,and adopt two methods for processing of optimal sensor placement that modal strain energy coefficient and effective independence. Process of optimal sensor placement uses structural dynamic characteristic,and uses the theoretic data of finite element model(FEM) analysis as calculating original data. The methods uses in this paper to processing of optimal sensor placement are modal strain energy coefficient and effective independence method. Three optimal principles of sensor placement,Error Discerned Minimum? Displacement Energy and Model Reduction,have been discussed on the relativity of modes and the displacement. Reduced method has been proposed based on the principle of reducing the freedom affecting objective the most to prune one by one. Using these two methods, has received the good optimal results. Under the situation of assuming that the structure is being damaged (structure quality does not change , rigidity changes ), adopt way to expand steps of shaking etc. and decorate and verify with three BP neural network procedure sensor in structure, have reached the good result;And has made comparisons to two kinds of method income results , has proved and had nothing to do the superiority of the method effectively independence; The sensor which provides three kinds of structure fixes up the scheme.
|
PDF Full Text Request