Research On Multi Variety And Small Batch Scheduling For Complex Manufacturing System

With the development of advanced manufacturing technology,industrial robots are widely used in automated production systems,manufacturing industry is moving towards automation and intelligence,and the global market competition is becoming more and more fierce.At the same time,product performance and structure are developing toward complexity and refinement,and the production is characterized by multiple varieties and small batches.This makes the complexity of production process and management work increase dramatically.The traditional production mode is no longer suitable for the diversified market trend,and an efficient scheduling algorithm is needed to solve the multi-variety and smallbatch scheduling problem under the complex manufacturing system,so as to meet the demand of today’s manufacturing enterprises.Based on the classical job-shop scheduling theory,this paper studies the multi-variety small-batch scheduling problem for complex manufacturing systems,establishes a mathematical model to minimize the maximum completion time,proposes a new two-stage scheduling algorithm based on a single solution,and investigate the effectiveness of the algorithm through case analysis,comparative experiment,and project test.The main research contents of this paper are as follows:(1)The practical application of the project in the machine parts manufacturing enterprise is described,the source of the subject is explained,and the structure layout and scheduling characteristics of this kind of production workshop are introduced,which leads to the multi-variety and small-batch scheduling problem for complex manufacturing system.This problem is closer to the actual production needs and more complex.Multiple handling robots in the robot manufacturing unit have independent working areas,and there are several parallel processing equipment in the workshop.These equipment input buffer and output buffer capacity is limited,and the production task presents the characteristics of multi-varieties and small batches.The constraints and production conditions of this kind of problem are analyzed,some special constraints in actual production are added under the traditional constraints of job-shop scheduling,and the mixed integer linear programming is given.(2)A new two-stage scheduling algorithm based on single solution is proposed to solve the multi-variety small-batch scheduling problem in complex manufacturing system with the optimization goal of minimizing the maximum completion time.The algorithm adopts co-coding and optimization of operation sequence and equipment assignment.The whole algorithm is divided into two stages: initial solution construction and local search.In the first stage,a rule-based multi-level feedback queue scheduling algorithm is used to obtain an excellent and feasible initial solution in a very short time.In the second stage,an adaptive iterative local search is used for the initial solution.In the local search,a variable neighborhood descending algorithm containing 9 kinds of neighborhood structures is used,and an adaptive updating mechanism is used to adjust the execution order of neighborhood structures.At the same time,a series of corresponding scheduling strategies are proposed for scenarios such as dynamic scheduling and multi-order production that may be encountered in actual production.(3)The practical application scenarios of the two-stage scheduling algorithm are introduced through case studies,and the proposed algorithm is compared and experimented with other researchers’ algorithms using actual project cases under the same problem model,while the algorithm is tested under various static and dynamic scenarios of the project to verify the effectiveness of the algorithm.Finally,the workshop scheduling system is designed and implemented in B\S architecture,and the main functions of the scheduling system are introduced and the output interface of the scheduling scheme is shown.