Research And Implementation Of Visual Function Block Based On PLCopen

In the industrial field,machine vision has been widely used in production.Due to the arrival of Industry 4.0,the needs of intelligence increase.Traditional automation vendors also have a combination of PLC and machine vision and produce many mature visual products.However,different manufactures use different visual product solutions and different vision modules lack a unified interface.As a result,the visual module reuse is very poor,which greatly inhibits the development of machine vision industry.PLCopen is an international organization committed to the standardization of the field of industry.We hope to build a reusable visual function block library,which is consistent with the PLCopen specification.In this paper,the function block of PLCopen specification is studied,and the standard of visual function block is proposed which is accordance with PLCopen specification.Combining the features of image processing,the model and interface definition of visual function block are presented.In order to improve the design efficiency and security of vision system,a state model is designed to control the execution flow of visual function block and exception handing mechanism is proposed.The library of reusable image function is completed and the library is described by XML.Based on the above research results,I develop the CASS visual platform.All the algorithm of vision function block is added to the platform.The proposed design method is vertified and the open and reuse of PLCopen standard is proved.At the same time,the rapid development of the visual module is realized by the CASS vision platform.