| With the vigorous development of "made in China 2025" and industry 4.0,the manufacturing industry has completed the transformation from traditional manual operation to man-machine cooperative operation,and developed to fully automated operation.Industrial automation has gradually become the development trend in the future.Especially since 2020,the spread of the global epidemic has led to the rise of labor costs and accelerated the automation process of the manufacturing industry,In order to maintain efficient production,various types of cooperative robots have been widely developed and put into use,but users lack the means to perceive the state of robots.In the process of man-machine cooperation,once the equipment fails,it may cause unpredictable danger to users.Digital twin technology provides a new means to solve the problem of cooperative robot condition monitoring,Taking a certain type of cooperative robot as an example,establishing a digital twin system of cooperative robot with condition monitoring function.The main research contents of this paper are as follows:Firstly,Analyze the digital twin’s technology system,use mainstream five-dimensional pattern,the digital twin system architecture of cooperative robot condition monitoring is built.The architecture is divided into physical entity layer,virtual model layer,data layer,connection layer and functional service layer,and the system design principles and objectives are defined.After that,the virtual data acquisition platform is built based on the entity and robot.Aiming at the data acquisition platform,this paper defines the data types and acquisition methods of the physical robot,discusses the construction of the data platform from three aspects:receiving and processing data,providing external data access interface and ensuring data security by means of data cache,and designs relevant database tables to store the total data of the system;For the virtual model layer,the secondary development of the model is carried out by using SolidWorks software,and the parent-child relationship of the virtual model is divided to meet the motion consistency between the virtual model and the solid robot.Then,in order to reduce the system consumption of the model in storage,transmission and rendering and improve the system performance,the virtual model is simplified,In the aspect of model simplification,the triangular total curvature factor is introduced to optimize the edge folding algorithm,so that the details of the original model can be better preserved when simplifying the virtual model,and then the virtual model is displayed and presented by using unity 3d software.Then,based on the data layer and virtual model layer,the array twin system function service layer is built to realize three main functions:Based on robot kinematics,the data fusion driving script is designed and developed to successfully fuse the model and data and realize the virtual motion following function;Based on the visual chart,the visual presentation function of the real-time running state data of the robot is realized;Based on the multi-level fuzzy comprehensive evaluation method based on fuzzy mathematics theory,the real-time health status evaluation function of robot is realized.In this method,the evaluation factor set is established by FMEA and FTA analysis,the evaluation result set is established by the health five point method,the evaluation factor weight is established by the combined weighting method combining the coefficient of variation method and entropy method,and the evaluation matrix is established by the membership function modified by real-time data,By comparison,the weighted average operator is selected to evaluate the system health.Finally,the digital twin system is integrated,the functional requirements of the system are analyzed,the system UI interactive interface is made,and the data information such as robot acceleration and force that can not be collected by the system is supplemented by means of ADAMS simulation,so as to improve the digital twin system,After that,VR technology is used to make the virtual reality scene of the system to provide immersive interactive experience,and then the digital twin system is tested and displayed as a whole,which provides a reference for the condition monitoring of cooperative robot. |
