Study On Quick Virtual Changeover Technology For Mobile Phone Assembly Line Based On Open Architecture

With the rapid development of the mobile phone consumer market,the competition in the industry is increasingly fierce,and the frequency of mobile phone product iterations is happening faster.The production mode of multi-variety and small-batch orders forces the mobile phone assembly line to changeover and reconfigure frequently.The system downtime takes an increasing proportion in the whole production process,and the production capacity of the production line is not fully released.The changeover process of production line can be divided into three stages: external operation,internal operation and adjustment operation.Reasonable optimization of the three stages can shorten the line changeover time of the production line and improve the reconfiguration efficiency and production capacity of the production line.In view of the above problems,this paper takes the changeover process of the mobile phone assembly line as the research object.Based on the integration of SMED of industrial engineering with RMS,a QVC(Quick Virtual Changeover)method is proposed and its key enabling technology is studied from the perspective of different layers of the manufacturing system,namely,equipment layer,control layer,and system layer.The main contributions can be concluded as follows:Firstly,an open architecture design method for mobile phone assembly lines is proposed,and the structure of the mobile phone assembly line is optimized for compressing the internal operation time during the production line changeover process from the device layer.Specifically,the open pipeline line design can be well adapted to the three operation modes,namely,full manual mode,full automation mode,and humanmachine duplex mode.The dynamic tissue flexibility of the production line in different operation modes is increased.By adopting an "Universal Base + Robot + Custom Modules" architecture mode to design a Plug-and-Play mobile phone assembly line automatic processing equipment,it reduces the threshold for introducing automation equipment in the mobile phone assembly industry,and solves the "device island" issue formed by the incompatibility of automation equipment.The equipment development cycle and the time of equipment module replacement/adjustment are shortened during the production line changeover process.The open architecture of "Open Line + Plug-and-Play Device" plays a vital role in achieving the quick changeover goal.Secondly,an integrated simulation test method is established for virtual debugging of physical equipment,and the operating operation time is adjusted during the process of reconfiguring the line from the control layer.Specifically,the rapid customization design method is used to perform parametric object packaging on the physical equipment of the line to form a digital prototype dedicated library,and to realize the virtual integration and off-line simulation operation of the whole line of the production line.A digital communication technology is developed to build the information communication channel between the virtual model and the physical object.The cyber-physical debugging between the simulation model and the physical device is performed,for verifying the consistency of the action logic of the control network and the control program,and thus avoiding the time cost of controlling program errors in advance.Finally,this paper evaluates and optimizes the changeover scheme based on the simulation platform,and the high-quality quick changeover is realized for compressing the adjustment operation and external operation time from the system layer.Specifically,the Petri net is used to model and analyze the changeover scheme of mobile phone assembly line,and the changeover time cost under different changeover schemes is evaluated.A better changeover scheme is obtained.Through the platform,with the optimization of production capacity and equipment utilization,a simulation operation optimization for a given production line plan is performed.