| The liner coaxial parameters directly affect the performance of artillery shells and missiles, but the coaxiality of the current domestic means is still very backward, coaxiality testing has become a disincentive to further improve the properties of shells and missiles.Based on this, the paper designs a method to detect the coaxiality of the liner based on PSD, in which laser light is used as foundtional axis, PSD is used to measure the position change of the center of the liner's holes. The data is send to the computer which measures and deals with it through its acquisition and serial transmission. We focus on the study of nonlinearity of planar PSD output and the non-linearity correcting method of the Backpropagation NN. After simulation of Backpropagation NN, the output of PSD has well linearity. Through the analysis of theory and experiment, the article discusses the influence of testing condition on detection precision of PSD and proposes measures to overcome the interference. Finally, it proves that the method can meet the accuracy requirements 0.05mm of the system by analyzing the experiment result. |
