Alfred Theorin

• Lund University

Future manufacturing systems need to be more flexible, to embrace tougher and constantly changing market demands. They need to make better use of plant data, ideally utilising all data from the entire plant. Low-level data should be refined to real-time information for decision-making, to facilitate competitiveness through informed and timely decis...

Control applications contain both logic, sequencing, and control algorithms. A holistic view of this is seldom presented in teaching and papers. One reason is the separation of communities — automation groups typically come from the Programmable Logic Controller (PLC) world while control engineers primarily come from the Distributed Control System...

Abstract The PID controller is by far the most common controller, and to ensure good behavior under all circumstances, a PID implementation must consider many practical aspects such as integrator windup, derivative kick, and bumpless parameter and mode changes. In this paper, an entirely new issue for the derivative part is introduced and has been...

Future manufacturing systems need to be more flexible, to embrace tougher and constantly changing market demands. They also need to make better use of plant data, ideally utilizing all data from the entire plant. Low-level data should be refined to real-time information for decision making, to facilitate competitiveness through informed and timely...

To fulfill increasing requirements in the manufacturing sector, companies are facing several challenges. Three major challenges have been identified regarding time-to-market, vertical feedback loops, and level of automation. Grafchart, a graphical language aimed for supervisory control applications, can be used from the process-planning phase, thro...

Production plants need to be set up and reconfigured faster to fulfill increasing market demands. Highly flexible automation systems are needed and a promising approach is Service Oriented Architecture (SOA) which has recently received much attention in both academia and industry. OPC Unified Architecture (OPC UA), the next generation of the de fac...

The PID controller is the most common controller today and is taught in most introductory automatic control courses. To develop an intuitive understanding of the basic concepts of the PID controller and PID parameter tuning, interactive and freely available tools are important. A PID module for educational purposes has been implemented in JGrafchar...

Grafchart is a graphical programming language which extends Sequential Function Charts (SFC), the PLC standard languages for sequential, parallel, and general state-transition oriented automation applications. SFC is widely used and accepted for industrial automation. Grafchart adds higher level features to SFC such as hierarchical structuring, reu...

Innovative engineering methods are needed to enhance the adaptability and agility of industrial control procedures and concurrently manage their rising complexity. Service-oriented Architecture (SOA) constitutes a promising paradigm to meet these challenges. To apply the rather abstract SOA principles to industrial automation, a model-driven engine...

To fulfill increasing requirements within the manufacturing sector, highly flexible and adaptable automation systems are needed. It is desirable to have one integrated approach that stretches from the process planning phase, through the implementation phase and all the way to the phase for execution of the process control logics. One promising appr...

Grafchart is a graphical programming language for sequen- tial control applications. It exists in two versions: the basic version (BV) and the high-level version (HLV). The currently used Grafchart tool, JGrafchart, only supports BV. To enable further research on HLV, it must be supported by JGrafchart. Since HLV is a superset of BV it is desirable...

In production industry today a lot of engineering time is required to develop and maintain control applications. One part of the control applications are the state machines which typically are written in Grafcet/SFC. Several efforts have been made to extend Grafcet/SFC to achieve more effective and convenient development, e.g. by introducing hierar...

The trend in manufacturing industry today is that the complexity of the manufacturing equipment is increasing. At the same time the requirements on vertical integration and faster set-up and adaptations are increasing. To cope with this, highly re-usable, flexible, and adaptable automation systems are needed. One promising technology is Service-ori...

To fulfill increasing requirements within the manufacturing sector, highly flexible and adaptable automation systems are needed. It is desirable to have one integrated approach that stretches from the process planning phase, through the implementation phase and all the way to the phase for execution of the process control logics. One promising appr...

To fulfill increasing requirements in the manufacturing sector, companies are faced to several challenges. Three major challenges have been identified regarding Time-to-market, vertical feedback loops and level of Automation. Grafchart, a graphical language aimed for supervisory control applications, can be used from the process-planning phase, thr...