Research And Application Of Task Granularity Of Complex Heavy Equipment In Cloud Manufacturing Environment

As one of the key strategic industries of the country,complex heavy equipment manufacturing industry has developed rapidly in recent years,but the market’s requirements for its manufacturing are also increasing day by day,such as higher quality,shorter delivery time and more competitive price.Complex heavy equipment has long development cycle,complex structure,a wide variety of processes,large manufacturing volume and high technology content.In cloud manufacturing environment,its manufacturing mode is mostly: one project general contractor,multiple cooperative enterprises.In this paper,the complex heavy equipment manufacturing system contracted by the design company is studied.In the cloud manufacturing environment,the general contractor of the project supervises and controls the project through the cloud platform.The whole project execution process of complex heavy equipment involves many links,and there are many responsible subjects in each part.In this paper,according to the differences in the attention of the general contractor to each link of the project,the management level and management detail degree of each link are analyzed,and the task granularity scheme is proposed in combination with the characteristics of equipment structure level and resource characteristics of each link.Firstly,a task granularity partitioning scheme based on task library is proposed.By decomposing and analyzing the structure hierarchy of complex heavy equipment,the meta-task library is constructed to manage and invoke tasks according to the structure hierarchy of equipment.According to the characteristics of tasks in each link of the project and corresponding resources,a standard task library is constructed based on historical tasks to provide reference for granularity partitioning of new project tasks.A task granularity partitioning method based on task library is proposed,which includes referring to standard tasks when standard tasks are available,and invoking tasks from meta-task library according to equipment structure when no standard tasks are available.Standardize the task granularity partitioning process.Then,considering the resource constraints in the process of task planning,a task granularity adjustment and determination method based on resource constraints is proposed.According to the resource attributes considered in resource management,resource matching and optimization of the platform,the resources are described in a unified form,and then the matching index and optimization index of the resources are analyzed.According to the task situation,the hierarchical clustering algorithm is used to consider the resource constraint clustering task or to adjust the task granularity considering the resource constraint.Then,a resource optimization model is established and solved by NSGA-II algorithm to obtain the optimal task-resource combination.Finally,the design task and manufacturing task of the main body of 125 MN extruder are analyzed as an application case.According to the scheme and method designed above,the component-level design task planning scheme and the key component main cylinder manufacturing task planning scheme are obtained.