Research On Real-time Scheduling Decision Mechanism Oriented To IoT-Based Manufacturing Environment

With the improvement of consumption concept,customer demand has presented a dynamic,diversified and personalized trend.This leads to the manufacturing industry falling into a dynamic and changeable environment.IoT-based manufacturing system can realize Real-time feedback of production control,real-time tracing of product information and real-time perception of disturbance event by using the sensor network and communication network.In the current manufacturing environment,there is higher frequency of disturbance and more uncertainties.The technology of IoT-based manufacturing has been one of the most important technologies to improve the efficiency of modern manufacturing system,especially shop floor production scheduling system.In this paper,the IoT and shop floor scheduling technology is combined,the real-time scheduling decision mechanism oriented to IoT-based manufacturing environment was researched,and an IoT-based manufacturing real-time scheduling system solution is proposed.The structure of this paper is as follows:Firstly,a hierarchical heterogeneous hybrid control architecture for MAS and IoT-based manufacturing is proposed and a MAS-based shop floor scheduling model is designed.These form the overall scheme of IoT-based manufacturing real-time scheduling system.Secondly,an event-driven rolling window scheduling mechanism is selected as the real-time dynamic scheduling mechanism of the system.The window-driven event is defined,and an improved single-step pre-rolling window rolling method is proposed,which improves the real-time computation speed and efficiency of the system.Then,the MAS real-time scheduling algorithm is studied.In this paper,an improved contract network protocol is proposed to coordinate agent behavior in MAS;a scheduling task evaluation algorithm based on allocation rules is designed to evaluate MAS scheduling tasks;and the scheduling cases were designed to compare and analyze the performance of two kinds of scheduling Model based on different allocation rules.Finally,according to the design scheme of the IoT-based manufacturing real-time scheduling system,an IoT-based manufacturing simulation experiment platform is built.The main hardware and software system of the experimental platform is designed,as well as the IoT-based manufacturing environment of the platform is built.The simulation experiments are carried out by using the simulation experiment platform.And the results verify the feasibility of the IoT-based manufacturing real-time scheduling system.