Study On Large Dimension Measurement Of Large Equipment During Assembly Process

The large-scale precision measurement of large-scale equipment assembly process is related to the performance,operating quality,and service life of the entire equipment.Therefore,the study of large-scale measurement methods has far-reaching significance for the impact of large-scale equipment,especially in high-precision,large-scale,and no guideway.In terms of measurement,the study of measurement methods is even more remarkable.At present,scholars at home and abroad have done a lot of research on large size measurement,and have made remarkable achievements in the measurement of high precision,large range and no guide rail,but the research on high efficiency and high precision measurement method for complex and changeable assembly site needs to be improved.Therefore,a laser pulse measurement method based on parallel counting is proposed in this paper to achieve large size,high accuracy and no guideway on-site measurement.The specific work of this article is as follows:First,the existing large size measurement methods and application status are summarized,and the large size measurement methods based on various measuring principles such as mechanical,acoustic and optical are introduced.The method of laser pulse measurement based on parallel counting is proposed,and the large size measurement system in the assembly process of large equipment is constructed,and the measurement is detailed.The measuring principle,components and working process of the measurement system are discussed.Secondly,in view of the drift error caused by the pulse broadening caused by the reflection characteristics of the target surface,this paper reduces the influence of the pulse broadening on the measurement accuracy by a specific method,and puts forward the method of the frontier identification for the imprecise pulse signal caused by the inaccurate selection of the time,and selects the appropriate threshold by selecting the appropriate threshold.The effect of the drift error on the measurement accuracy of the system is reduced.Based on the influence of the noise and clutter on the laser pulse signal,the effect of the signal to noise ratio and the waveform on the measurement accuracy ofthe system is reduced by the homomorphic filtering method,and the nonlinear error caused by the uneven phase shift of the clock pulse is caused by the pulse shaping.In this paper,a nonlinear compensation model is built based on BP neural network to reduce the influence of nonlinear error on the measurement accuracy of the system.Finally,in the large frame assembly site,the measurement principle of the large size measurement system proposed in this paper and the method of improving the measurement precision are carried out,and the feasibility of the measurement system is verified by the field test.