Measuring The Deformation Of An Object Using Three-dimensional Surface Measurement Technology

The measurement of the three-dimensional shape change of the object is realized by using the frequency doubling grating phase shift three-dimensional surface measurement technology.Traditional optical interference or holographic interferometry technology requires very stable holographic test bench and harsh experimental conditions without external interference when measuring the shape change of an object.This makes the measurement only possible under laboratory conditions and limits the practical application of the measurement technology range.The use of frequency doubling phase shift grating projection technology can realize the measurement of the three-dimensional shape change of objects in the natural environment,so that the precise deformation measurement technology is gradually expanded to various fields of industrial production and daily life.The frequency doubling grating phase shift technique is introduced in the experiment to reduce the cumulative error generated in the phase expansion,which can improve the accuracy of the measurement.In general,experiments using the frequency doubling grating phase shift technology require zero calibration in the calculation process to achieve higher accuracy and better results,and the frequency doubling grating phase shift 3D surface measurement technology is used to measure the three-dimensional deformation of the object.The same calculation accuracy can be achieved without zero calibration during the process,which simplifies the writing of calculation programs.This experiment has a simple optical path,low environmental requirements,short measurement time,effectively reduces analysis and calculation,and provides an effective means for measuring the deformation of objects.The main research work is as follows:1.A frequency-doubled raster image for projection is produced.Seven sets of spatial frequencies with four different phases of sinusoidal raster images were produced using the written computer program,and they were made into slides for projection in a certain order.2.Established a three-dimensional profile measurement system for measuring the deformation of objects.The optical projection system is used to project the produced grating slides with different frequencies and different phases on the surface of the object that has not been deformed.The camera system collects the fringe image that deforms with the fluctuation of the object surface.After the object is deformed,repeat the above process.3.Compiled the calculation program to measure the deformation of the object using the frequency doubling grating phase shift three-dimensional surface measurement technology.Use the collected fringe images to obtain the wrapped phase of each pixel,and expand the wrapped phases to obtain the three-dimensional surface height distribution information before and after the object deformation.The corresponding difference between the two sets of data is obtained.The three-dimensional shape of the object changes.