Research On Evaluation Method For Extracting Center Of Structured Light Stripe

The laser emitter transmit certain width strip on the surface of the projected object in space in the line structured light vision measurement system.The geometry information of the surface reflected by casting light strip center.This information is the most direct and important information is needed in the process of measurement.Therefore,the important condition for extraction final results accuracy of line structured light center line,is the accuracy and precision of line structured light stripe center extraction.The characteristics of laser light is embodied in the different facts,including width,uneven illumination and different brightness level,etc..In the face of object surface with diffuse reflection area and the strong reflection area,light image will be generated.The huge contrast error is from the measured object surface properties of randomly generated,which is projected onto the measured object fixed laser with different degrees of dispersion.The different noises generated by the camera can also affect the image of the light stripe,which brings difficulty to the image processing and the extraction of the characteristic light strip center,and the measurement error is produced.Based on the two kinds of typical material objects as the research object,which is common in the industrial production of ceramic and metal surface bright silver items are ceramic cups and metal flagon.Based on the measuring principle of laser triangulation by filtering and smoothing.More clear and accurate image extraction method for image processing is obtained.By using two kinds of light stripe center,these two methods have strong pertinence,high accuracy,and can effectively extract light strip center,and avoid the noise generated in the process of measurement,the error caused by the light.The main work of this thesis: according to rhe preliminary collected light images,fractional differential method and histogram normalization method is used to filter images.And use sub-pixel edge detection method to get the image smoothe.The measured object uses the Improved Grayscale Gravity Method and improved Hessian matrix method for light stripe center extraction material characteristics,to obtain more accurate experimental data.Respectively to two kinds of light extraction methods to study the data comparison and evaluation,effectively solve the interference with light stripe center extraction in the problem of poor accuracy.