Research On Interruption Effect And Strategy Of Light Assembly Operation Based On NIRS And EEG

With the continuous improvement of the socioeconomic level,the increasing of consumer demand for personalized products and the mass customization and increasingly fierce competition,enterprises are forced to adopt multi-product mixed-flow production to improve market responsiveness.Mixed-flow production requires operators to be in a multi-tasking state for a long time.There are so many random disturbances in the production process that the operator's operational performance often faces the impact of work interruption.At the same time,the parts are small in size and low in degree of differentiation in light assembly operations.Operators need to be highly focused on identifying,retrieving,locating and assembling components.Interruption not only interferes with operational performance,but also causes the operator's attention shifts because the re-recovery to the previous work task requires more cognitive resources.Operators are prone to distraction and cognitive overload,which leads to increased probability of human error and safety accidents,and is not conducive to sustainable and efficient production of enterprises.However,in the previous research on the interruption effect of light assembly operations and the formulation of management strategies,the main concern is the loss of operator's operational performance.Further research is needed on the physiological state of operators'attention resource demand and cognitive load as well as the underlying neural influence mechanism.Therefore,based on the previous field research and review of relevant literature,the Lego model is used to represent light assembly operations such as electronic products,instrumentation,control devices and flexible circuit assembly.Enterprise production is actually restored in the laboratory environment.A simulated light assembly experiment is designed with interruption complexity?simple;complex?and similarity?similar;dissimilar?.Experimental studies can control experimental variables and production conditions,and it can verify optimization and improvement scenarios.The operating performance and error rate indicators of 20 operators were recorded through the on-site recording and video recorder methods.Physiological data of oxyhemoglobin in the left and right anterior frontal lobe and their changes were collected and monitored by NIRS equipment.EEG signal data and their changes at F_Z,F₃,F₄,C_Z,C₃,C₄,P_Z,P₃,and P₄ were collected and monitored by EEG equipment.Through the combination of the data of pre-frontal blood oxygen changes,EEG changes in different brain regions at various stages of interruption and the behavioral data such as time and error rate.The cognitive load,attention resource demand and operational performance of different stages under the interruption effect are analyzed.The research finds that the similarity of interrupted tasks has significant effects on cognitive load and attention resource demand.Dissimilar interruption will result in an increase in the operator's cognitive load and attention resource requirements,and a decrease in the operator's operational performance after the interruption.The study reveals the change rule and internal mechanism of the operational performance,cognitive load and attention resource requirements in the light assembly operation.It also proves the hypothesis of the Memory for Goals Theory,the Cognitive Load Theory about the interruption mechanism,the working memory storage,and the psychological resource allocation.On this basis,this study gives an interrupt processing priority order that considers operational performance,error rate,cognitive load,and attention resource requirements:complex dissimilarity>complex similarity>simple dissimilarity>simple similarity.The strategy of interrupt training and recovery is put forward,and relevant management countermeasures and suggestions are given for the time planning,pre-job training,restoration rest system and job rotation system of light assembly enterprises.Considering the heterogeneity characteristics of different employees,this study proposes the use of quadrant map to distinguish different types of operators,and the operator heterogeneity management strategy for the matching of people and posts.Finally,this study proposes an interrupt management mechanism for cognitive load embedding,and gives relevant suggestions and measures for the identification of interrupts and the timing of interrupts.This can be used to guide the light assembly enterprise managers to rationally formulate the interrupt management strategy,to improve the production efficiency of enterprises,to reduce the cognitive load and attention resource requirements of operators,and to achieve sustainable and efficient production of enterprises.