Research On Scrap Metal Identification And Separation Control Technology Based On Dual Energy X-ray Transmission

The recycling of scrap metal resources can alleviate the pressure of environment and resources which caused by the exploitation of primary mineral resources and promote sustainable development.Scrap metal can be reused by casting.In order to save the cost of scrap metal recycling,scrap metal should be sorted and recycled by type.In the process of scrap metal separation based on dual energy X-ray transmission technology,scrap metal materials’ identification was impacted by its thickness and the accuracy of the final separation was determined by the separation control technology.In order to improve the accuracy of separation of the scrap metal separation system,scrap metal materials’ identification algorithm and separation control technology based on dual energy X-ray transmission technology were studied in this paper.In this paper,the dual energy curve fitting algorithm and R-value algorithm are analyzed,firstly.Aiming at the problem that scrap metal materials’ identification was impacted by its thickness,R-value algorithm was optimized by applying composite numerical integration,which based on the R-value and low transmission signal curve algorithm.An algorithm about curve fitting of R-value based on composite numerical integration was proposed.The influence of thickness factor on scrap metal materials’ identification was weakened and the algorithm was verified by experiments.The material’s type and location information need to be obtained,when scrap metal materials were controlled to be separated.When calculating material’s location information,image processing technology was used to process the X-ray transmission signal.An improved method was proposed based on the shape center algorithm of the binary image.The shape centers of multiple objects can be calculated.The problem of the detection data of the same material was divided into two images can also be solved.The positions and types of metal materials were matched.Based on the existing hardware platform,two separation control methods are proposed.First,the proximity switch is used to detect the arrival of the material and the feedback signal is given to the control system,then the metals materials were separated according to the feedback signal.Another method is by taking advantage of Windows multimedia timer function to determine whether the materials arrive at the position of separation by means of time delay,then metal materials separation was completed.Finally,material separation control and the accuracy of material’s position calculation was verified by experiments.