| 1. |
- Carlsson, Henrik, 1979-, et al.
(författare)
-
A General Virtual Manufacturing Concept for Programming, Verification and Optimisation of Complex Control Functions
- 2008
-
Ingår i: Proceedings of the 18th International Conference on Flexible Automation and Intelligent Manufacturing, FAIM 2008: June 30th - July 2nd, 2008, University of Skövde, Sweden. - Skövde. - 9789163327575 ; , s. 668-675
-
Konferensbidrag (refereegranskat)abstract
- This paper describes a general virtual manufacturing concept for industrial control systems. Our virtual manufacturing concept provides a distinct advantage; programming, verification and optimisation of complex real-time dependent control functions described by real control code, which can be directly transferred to the real manufacturing system. To achieve this distinct advantage, a time synchronised virtual manufacturing system is a necessity. The aim of this paper is thus to present and to describe in detail, our proposed virtual manufacturing concept. To the authors’ knowledge no such general virtual manufacturing concept, i.e. one that can correctly handle complex real-time dependent control functions, currently exists. To summarise previous work related to virtual manufacturing and industrial control systems, several critical issues have been identified. The virtual manufacturing concept proposed in this paper addresses these issues. To verify that our concept can manage these critical issues found and further is suitable in industrial applications a virtual manufacturing test case is also presented. The test case, that includes motion control (i.e. servo), complex control functions, real control systems etc., was carried out with success.
|
|
| 2. |
- Carlsson, Henrik, 1979-, et al.
(författare)
-
Automated Generation of Discrete Event System Simulation Models for Flexible Automation
- 2011
-
Ingår i: The 21st International Conference on Flexible Automation and Intelligent Manufacturing. - 9789868729100 ; , s. 825-832, s. 825-832
-
Konferensbidrag (refereegranskat)abstract
- Flexible automation cells with rapid product changes are an important competitive advantage for industries today. These cells can increase a company’s productivity and thereby increase their profits. A flexible cell shall be able to handle different products with none or minimal changes to the cell itself. A powerful tool, which can be used to analyse and verify such cells, is discrete event system simulation. Problems such as potential bottlenecks, deadlocks, answers to "what-if" questions and the level of resource utilisation can be gathered. The drawback of discrete event system simulation is that the modelling task is both time consuming and difficult to accomplish. Furthermore, state-of-the-art discrete event system simulation tools that are used in the industry today are not suitable for flexible automation. If the production scenario is changed, e.g. introduction of a new product, the simulation and modelling has to be redone and this is both time consuming and tedious. In this paper a new approach will be presented that enables discrete event simulation models to be generated automatically. The models are generated from information retrieved from a PLM/PDM database system, which is shared among other engineering tools such as robot simulation, CAD and process planning. Hence, when the cell and the database are updated a new model can easily be generated. The database is also connected to the real cell so up-to-date data can be retrieved from the real cell. The model generator described in this paper was implemented and tested in a discrete event system simulation tool and showed promising results. With this approach it is possible to handle flexible automation cells more effectively in a process planning stage.
|
|
| 3. |
- Carlsson, Henric, 1979-, et al.
(författare)
-
General Time Synchronisation Method for PLC Programs Aiming at Virtual Verification and Development
- 2008
-
Ingår i: 17th IFAC World. - 9783902661005 ; , s. 4440-4445
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The latest state-of-the-art Computer Aided Production Engineering (CAPE) simulation technology offers OPC integration for PLC verification. A critical drawback with this technology has been identified and described within this paper. A new time synchronisation method and a simulation architecture are therefore presented and proposed. The time synchronisation method together with the architecture can be used when verifying and developing real-time dependent control logic for industrial control system, e.g. PLC with CAPE tools. The method described in this paper is general and should work on any PLCs that are compatible with the IEC 61131-3 standard. A test case was also carried out, showing that by disregarding time synchronisation it is impossible to verify real-time dependent PLC functions together with CAPE tools in a reliable way. However, the test case also shows that by applying the proposed time synchronisation method together with the described simulation architecture a successful industrial verification method is achieved
|
|
| 4. |
- Carlsson, Henrik, 1979-, et al.
(författare)
-
Methods for Reliable Simulation-Based PLC Code Verification
- 2012
-
Ingår i: IEEE Transactions on Industrial Informatics. - 1941-0050 .- 1551-3203. ; 8:2, s. 267-278
-
Tidskriftsartikel (refereegranskat)abstract
- Simulation-based programmable logic controller (PLC) code verification is a part of virtual commissioning, where the control code is verified against a virtual prototype of an application. With today's general OPC interface, it is easy to connect a PLC to a simulation tool for, e. g., verification purposes. However, there are some problems with this approach that can lead to an unreliable verification result. In this paper, four major problems with the OPC interface are described, and two possible solutions to the problems are presented: a general IEC 61131-3-based software solution, and a new OPC standard solution.
|
|
| 5. |
- Ericsson, Mikael, 1975-, et al.
(författare)
-
Off-line programming of robots for metal deposition
- 2005
-
Ingår i: Trends in welding research. - 0871708426 ; , s. 629-634
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Metal Deposition (MD) is a rapid prototyping technique to build parts by depositing metal in a required fashion. When a complex-shaped part is to be built, a simulation tool is needed to define robot trajectories. Three different simulation-based methods for robot trajectory generation are introduced and compared in this study. The methods are; reversed milling, adapted rapid prototyping and application programming in a computer aided robotics software. All methods were shown capable of creating robot paths for complex shapes, with the CAR software approach being the most flexible. Using this method, the geometry to be built is automatically sliced into layers and a robot path is automatically generated. The method was tentatively evaluated and appears to provide a powerful technique in the design and optimisation of robot paths for MD. Experiments showed that it is possible to manufacture fully dense parts using an Nd-Yag laser.
|
|
