George Pintzos

A Knowledge Based Collaborative Platform for the Design and Deployment of Manufacturing Systems

The PLM systems do not provide any link to actual performance indicators, related to cost, time, and quality parameters. This paper describes a collaboration platform, based on a semantic core that expresses knowledge about Products, Processes and Resources. The platform is internet based, connecting engineers in the extended enterprise with shopfloor personnel. The concept is based both on a series of distinct components and elements comprising the knowledge base, and on a set of software agents. The latter are interfaced with a set of Computer Aided (CAx) systems and provide decision support capabilities for the design of a production line.

Assembly precedence diagram generation through assembly tiers determination

The extraction of assembly information from product data has been researched for the past three decades, mainly due to the advancements in computer performance and CAD-related software. However, the manipulation and processing of CAD data for the automatic generation of assembly information have only been recently researched. This paper presents a methodology for extracting assembly information from product data. The methodology is based on a novel idea of assembly tiers for the separation of parts to be assembled into groups based on their geometric characteristics. The methodology is applied as a software extension to a commercial CAD software and is demonstrated through a number of industrial case studies.

An agent-based collaborative platform for the design of assembly lines

This paper presents an internet-based approach for the performance of assembly line balancing and design in an integrated manner. The resulting software is capable of generating, simulating and evaluating a series of alternative assembly line configurations and is implemented as a cloud service, taking into account diverse market and manufacturing scenarios. The platform, which the discrete applications are based on, is a multi-agent system comprising different software agents, which assist engineers in the collaboration processes. Special focus is given to the problem of designing mixed-model assembly lines based on the existing engineering information with new calculations. A multi-agent framework and a common data repository are used for the integration of the stakeholders along the engineering chain. The proposed approach is demonstrated through an automotive case study.

Reference Model Concept for Structuring and Representing Performance Indicators in Manufacturing

Performance indicators (PIs) are used to monitor and assess production systems. There are thousands of PIs described in standards or in commercial PI collections; however, the PIs implemented in the factories may differ enormously due to use-case-specific requirements. In this work a reference model is proposed to support the process from a generic description to a use case specific PI implementation. There are two exemplary implementations described utilizing data stream processing and database technologies.

An Integrated Approach to the Planning of Manual Assembly Lines

Manual assembly planning methodologies have been in the center of industrial and academic research for many decades, since the manual assembly costs may often account for even half of the total manufacturing expenses. The existing and emerging manufacturing trends, such as mass customization and personalization, require fast responses when it comes to the conception and realization of the relevant manufacturing systems. Even though, work methodologies, such as concurrent engineering, have been proposed and applied, gaps still exist among product development, configuration and manufacturing. The Current Product Lifecycle (PLM) systems focus on the coordination of activities among engineers of different disciplines. However, they are unable to provide actual decision support functionality to decision makers. Moreover, solutions for the different phases of assembly planning have been proposed, without nevertheless taking into account the holistic nature of assembly planning that spans the different engineering phases.The study presented in this paper is based on a methodology that integrates three distinct steps, regarding assembly planning; the generation of assembly related information, from the Computer Aided Design (CAD) files of an assembly, the calculation of the relevant process times from functions, generated through empirical measurements and the assembly line balancing of a line, based on the information gathered. The innovative aspect of this approach relies on the advancement of the relevant technologies as well as on their integration into a common working practice. The methodology enables the estimation of production related values in the later phases of product design or in the early phases of manufacturing planning. The generation of assembly precedence diagrams is made in an automatic way through the extraction of information on collision detection and the parts’ relations. This application is developed in the form of an add-on to a commercial CAD software suite. It utilizes features that are available in a wide range of such systems. The second step relies on the identification of specific features of parts, such as dimensions and mass. This information is then used as input in the functions already proposed in the academic literature for the estimation of the relevant process times for each part. Finally, the assembly line balancing is performed through the generation of the precedence diagram and the estimated process times, via a web-based service, which makes use of advanced optimization techniques.In order for this methodology to be evaluated, a case study is presented by using the CAD file of an automotive sub-assembly. The case study demonstrates each step separately, beginning with the generation of the precedence diagram down to the balancing of the assembly line.Copyright