Sotiris Makris

An intelligent search algorithm-based method to derive assembly line design alternatives

In this work, a method of deriving assembly line design alternatives and evaluating them against multiple user-defined criteria has been presented. The design problem has been formulated in a way that it can be transformed from a decision-making problem into a search problem. A systematic way of generating the solution space of the search problem, based on the real-life design project requirements, has been described in detail. An intelligent search algorithm that uses the three control factors to guide the search was introduced and applied to efficiently derive high-quality line designs. Investment cost, availability, equipment reutilisation, annual production volume and flexibility metrics have been used for evaluating the alternative designs. The method was implemented in a software tool, which can automatically generate discrete event simulation models for the calculation of several performance metrics. The results of the application, in an automotive case, indicate that the tool is appropriate for supporting decision making during the stage of rough planning, although several functionalities can be used during more advanced stages such as the detailed planning concept.

Towards the Internet-based supply chain management for the ship repair industry

A current trend of companies in the manufacturing industry is to operate globally in order to expand the limits of their business and integrate their operations with these of their business partners. The growth of the Internet and the software technologies that arise from it provides the means for this globalization. In this paper, we examine the problems arising from the integration of partners, who use heterogeneous information systems. The paper deals particularly with the ship repair industry as a case study of these problems and their solution. In this work, we demonstrate how modern information technology can support the communication of different partners and enable the information flow within the value added chain. Moreover, we describe how the performance of a supply chain can be improved by applying a generic hierarchical model though the appropriate planning of the critical manufacturing operations.

Human–robot interaction review and challenges on task planning and programming

The wide interest of research and industry in the human–robot interaction (HRI) related topics is proportional to the increased productivity and flexibility of the production lines, as it combines human and robot capabilities. This paper presents a review of recent research and progress on HRI, related to task planning/coordination and programming with emphasis on the manufacturing/production environment. Human–robot task allocation and scheduling, metrics for HRI, as well as the social aspects are reviewed. The role of digital human modelling systems for human–robot task planning related issues is also discussed. The process of learning by demonstration as well as the instructive systems is reviewed, focussing mainly on programming through visual guidance and imitation, voice commands and haptic interaction. The aspect of physical HRI as well as the safety related issues are also discussed. Additionally, a survey on multimodal communication frameworks is presented. Challenges encountered and directions for future research are discussed.

Industrial applications with cooperating robots for the flexible assembly

This article discusses the key features of cooperating robotic cells in the automotive assembly, highlighting the key elements in the engineers’ decision-making process, while designing and implementing an assembly line for the Body In White. The main issues, affecting the performance of cooperating robotic cells, are discussed with the aid of a case study, where two different scenarios are compared. The first scenario uses a conventional fixture-based configuration of a robotic cell for performing a welding operation, while the second features the use of cooperating robots. The cases are compared with the aid of a simulation platform, and future potential developments are also discussed.

The role of simulation in digital manufacturing: applications and outlook

Digital manufacturing technologies have been considered an essential part of the continuous effort towards the reduction in a product’s development time and cost, as well as towards the expansion in customisation options. The simulation-based technologies constitute a focal point of digital manufacturing solutions, since they allow for the experimentation and validation of different product, process and manufacturing system configurations. This article investigates simulation-based applications in a series of different technological and manufacturing domains. First, this article discusses the current industrial practice, focusing on the use of information technology. Next, a series of simulation-based solutions are explored in the domains of product and production process design, as well as in the area of enterprise resource planning. The current technologies and research trends are discussed in the context of the new landscape of computing hardware technologies and the emerging computing services, including the initiatives comprising both the Internet cloud and the Internet of things.

Virtual Commissioning of an Assembly Cell with Cooperating Robots

The Virtual CommissioningVCtechnology is the latest trend in automotive assembly which, among other benefits, promises a more efficient handling of the complexity in assembly systems, a great reduction in the systems ramp-up time, and a resulting shortening of the products time to market. This paper presents the application of VC techniques to the case of an industrial robotic cell, involving cooperating robots. The complete workflow of the virtual validation of the cell is presented, and the implementation requirements are discussed. Based on the findings, the outlook and challenges for the wide-range adoption of VC technologies in large-scale assembly systems are provided.

On a human-robot collaboration in an assembly cell

This is a study of a Human-Robot Collaboration (HRC) framework for the execution of collaborative tasks in hybrid assembly cells. Robots and humans coexist in the same cell and share tasks according to their capabilities. An intelligent decision-making method that allows human-robot task allocation is proposed and is integrated within a Robot Operating System (ROS) framework. The proposed method enables the allocation of sequential tasks assigned to a robot and a human in separate workspaces. The focus is rather given to the human–robot coexistence for the execution of sequential tasks, in order for the automation level in manual or even hybrid assembly lines to be increased. Body gestures are the means of a human’s interaction with a robot for commanding and guiding reasons. The proposed framework is implemented into a case coming from the manual assembly lines of an automotive industry. A preliminary design of a hybrid assembly cell is presented, focusing on the assembly of a hydraulic pump by robots and humans.

Supply chain control logic for enabling adaptability under uncertainty

This paper suggests a probabilistic inference method of quantifying a buyers likelihood to purchase a highly customised product. The probabilistic inference method utilises the principles of Bayesian networks. This method is integrated into an Internet based supply chain control logic where supply chain partners provide real time or near real time information, regarding the availability of parts needed for the production of highly customisable products. The supply chain plan that is generated is robust, ensuring the supply of the right part at the right time at a rather reasonable cost, thus eliminating the quality defects of the product. The concept is demonstrated in a typical supply chain case, taken from the automotive industry.

A concept for context-aware computing in manufacturing: the white goods case

A key characteristic for industrial production in the Industry 4.0 paradigm is the connection of physical items like sensors, devices and enterprise assets, connected both to each other and to the Internet. In this Internet of Things environment, things will sense more data, become context-aware and provide added-value information to assist people take more relevant and valuable decisions. Context-aware information distribution may offer substantial value to manufacturing. It provides task-relevant information or services to users in a manufacturing shop-floor improving decision making through context-driven recommendations. This paper presents a context-aware information distribution system to support users in an industrial environment. The system aims at utilising data collected from sensors located at a shop-floor in order to increase the visibility of shop-floor processes by providing the right information, to the right people, at the right time. The system’s architecture and key elements have been developed for a pilot implementation in the white goods industry and are presented in this study.

An agent-based methodology for manufacturing decision making: a textile case study

Decentralised decision making and real-time response to the unforeseen changes, often taking place in both the manufacturing and market environments, are two important factors that affect the flexibility, required for a production chain to follow demand. This article describes an agent-based methodology, for addressing both real-time and decentralised manufacturing decision-making challenges. At the manufacturing levels of production and processes, the agents employ a mechanism to generate local alternatives as well as a message exchange procedure to build decision trees, which are traversed and evaluated via user-defined objective functions. The generic structure used in the approach allows in a wide range the application of production system configurations. The real-time information, required for monitoring the system status and for generating valid alternatives, is obtained through integration with the existing information systems. An application to the textile industry is presented and discussed.