Hybrid Systems Diagnosis and Control Reconfiguration for Manufacturing Systems

Petri nets;Manufacturing;Hybrid systems

Propes, Nicholas Chung ; Electrical and Computer Engineering

University:Georgia Institute of Technology

Department:Electrical and Computer Engineering

关键词: Petri nets;    Manufacturing;    Hybrid systems;   

Others  :  https://smartech.gatech.edu/bitstream/1853/5150/1/propes_nicholas_c_200405_phd.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

A methodology for representing and analyzing manufacturing systems in a hybrid systems framework for control reconfiguration purposes in the presence of defects and failures at the product and system levels is presented.At the top level, a supervisory Petri net directs parts/jobs through the manufacturing system.An object-based hybrid systems model that incorporates both Petri nets at the event-driven level and differential equations at the time-driven level describes the subsystems.Rerouting capabilities utilizing this model at the product and operation levels were explained. Simulations were performed on a testbed model for optimal time and mode transition cost to determine the route for parts. The product level reconfiguration architecture utilizes an adaptive network-based fuzzy inference system (ANFIS) to map histogram comparison metrics to set-point adjustments when product defects were detected.Tests were performed on good and defective plastic parts from a plastic injection molding machine.In addition, a mode identification architecture was described that incorporates both time- and event-driven information to determine the operating mode of a system from measured sensor signals.Simulated data representing the measured process signals from a Navy ship chiller system were used to verify that the appropriate operating modes were detected.