Bruno Birgmajer

A matrix approach to an FMS control design [flexible manufacturing systems]

This article presents advantages of using new technologies and design methods for control of flexible manufacturing systems (FMS). For this purpose, a matrix-based description of FMS operations is adopted, as it generates the form of the FMS supervisory controller that is directly convertible into the programmable logic controller (PLC) program. An accent is given to the program tool FlexMan which enables elegant setting of complex FMS configurations by using virtual reality models and a matching matrix-based dynamic simulator. We demonstrate how this tool has been used for design, dynamic simulation, and visualization of a two-robot, material handling cell. It is shown how phenomena like operation conflicts and deadlocks can be observed and analyzed within a virtual reality environment before switching to the real world application. A comparison of results indicates large match-ups of phenomena in both environments.

Integrated vision system for supervision and guidance of a steam generator tube inspection manipulator

In this paper we present a machine vision system for supervision and guidance of a tube inspection manipulator used for eddy-current inspections of steam generators in nuclear and thermal power plants. Operation of nuclear power plants is regulated by very strict safety standards. In one inspection cycle a few hundred out of a mesh of approximately 6,000 tubes need to be tested, so omissions and misidentifications can occur. A supervisory vision system is introduced into the inspection manipulator motion control loop to increase its reliability and enable full automation of the inspection procedure. The developed system supervises robot movements over the tube mesh and verifies that the eddy-current probe is positioned into the desired tube. On final approach of the manipulator arm to the tube opening, the vision system automatically guides the manipulator to achieve accurate positioning for probe insertion, thus eliminating the need for operator input and reducing probe wear.

Fuzzy-Predictive Control of a Road Tunnel Ventilation System

In this paper we describe a control method for longitudinal ventilation of road tunnels. The method consists of two main elements: a) prediction of a number of jet fans and b) fuzzy control of pollutant levels. Based on measurements of traffic intensity and weather conditions and by knowing tunnel parameters, production of CO, NOx and small particles (soot) is predicted. Estimated values of pollutants are then used for calculation of fresh air volume demand, i.e. required air flow is determined. One dimensional force equation is used for estimation of a number of jet fans that would produce a thrust force sufficient to provide calculated air flow. In the same time a fuzzy controller compares measured and desired levels of pollutants and adjusts a predicted number of jet fans in order to keep the pollutant levels within predefined boundaries. The proposed method is tested by simulation and obtained results are compared with a method currently used in the ventilation system of the tunnel Ucka.

MODELING AND SIMULATION OF FMS DYNAMICS BY USING VRML

This paper presents advantages of using virtual reality FMS models and corresponding dynamic simulators for design, analysis, dynamic simulation and visualization of complex flexible manufacturing systems. Developed software has been used for creating a virtual model of the laboratory FMS setup. It is shown how phenomena like operation conflicts and deadlocks can be observed and supervised remotely through a client-server Internet connection.

Teaching flexible manufacturing systems by using design and simulation program tools

This paper describes the ways of using program tools for design and simulation of flexible manufacturing systems (FMS) for the purpose of teaching the undergraduate course Flexible Manufacturing Systems. The concept of the course is based on the synergism of theoretical knowledge and practical hands-on experience gained by studying numerous problem cases, using common tools for description of FMS (Petri nets, max-plus algebra and matrix modeling) and by working with more specialized program tools for FMS design and simulation. An emphasis is given to the description o the program tool FlexMan that enables elegant setting of an FMS configuration, supports automatic generation of a matrix-based FMS description and consequently, enables effective off-site design and simulation of the FMS by using virtual reality models and Internet-related technologies.