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One of today's most significant challenges is sustainability, which is closely linked to environmentally friendly solutions and resource efficiency. As a solution to these goals, the concept of the Physical Internet emerged, defining the logistics network of the future as a global, open, and interconnected system. Concerning the conditions of vehicles based on Physical Internet-based systems, we cannot ignore the latest vehicle technology innovations that appear more and more intensively in parallel. The framework proposes planning at the strategic, tactical, and operational levels. Different levels of coordination implement different approaches to platoon coordination in line with the network architecture of PI-based logistics systems. We recommend the highest level of offline design in fixed π-hubs. The tactical level involves designing π-hubs online. We propose the implementation of speed-based solutions at the operational planning level.

One of the biggest challenges today is to make traditional systems more sustainable. Physical Internet (PI, π) based logistics systems provide one of the most defining solutions. In our opinion, it is worthwhile to deal with the intralogistics conversion of the Physical Internet because traditional systems can no longer operate with sufficient efficiency to meet growing customer expectations and demands. This research focuses on restructuring a factory from its traditional operating to a PI-based system using our previously defined intralogistics components. The article surveys the possibility of creating PI-hub and virtual PI-hub in a factory process. The warehouses were converted to PI-hubs, and virtual PI-hubs were placed near the two manufacturing to create a more flexible structure. We created a simulation study in AnyLogic where we examine the efficiency achievable by automated guided vehicles (AGVs) in a PI-based system. The results were compared based on the traditional and PI-based systems. Based on the simulation the inefficiency of the PI-based system is lower (by ~18%) at higher control event values. This allows achieving a more efficient, flexible, sustainable, and balanced operation.

Physical Internet based supply chains create open, global logistics systems that enable new types of collaboration among participants. The open system allows the logistical examination of vehicle technology innovations such as the platooning concept. This article explores the multiple platoon collaboration. For the reconfiguration of two platoons a heuristic and a reinforcement learning (RL) based models have been developed. To our knowledge, this work is the first attempt to apply an RL-based decision model to solve the problem of controlling platoon cooperation. Vehicle exchange between platoons is provided by a virtual hub. Depending on the various input parameters, the efficiency of the model was examined through numerical examples in terms of the target function based on the transportation cost. Models using platoon reconfiguration are also compared to the cases where no vehicle exchange is implemented. We have found that a reinforcement learning based model provides a more efficient solution for high incoming vehicle numbers and low dispatch interval, although for low vehicle numbers heuristics model performs better.

With the development of industrial production technologies and market economy, Postponement is increasingly being adopted by continuous production enterprise as a method that enables multi-product, mass customization production. In order to make use of the Postponement in manufacturing production enterprises need to achieve customized production and reduce enterprise costs. A modeling is conducted in the production process of Postponement in iron and steel enterprises in this paper. With the goal of minimizing total costs on a specific customer service level, mixed integer nonlinear programming and particle swarm algorithms are adopted for modeling and solving, to determine the optimal location and optimal semi-finished product inventory of PDP and CODP. Finally, taking an iron and steel enterprise as an example, the feasibility and effectiveness of the model and algorithm are verified. The study shows that the change of the optimal locations of PDP and CODP is affected by the change of customer service level and delay penalty coefficient, but the speed of change of the optimal location of PDP shows longer delays. In addition, the size of the capacity of semi-finished product inventory corresponding to CODP has a direct influence on whether the semi-finished product inventory corresponding to PDP participates in production, which in turn affects the optimal semi-finished product inventory on all levels. Through the analysis, it is found that the model constructed in this paper can better describe the overall situation and the influence relationship of the Postponement, and the study supplements the deficiency of the research on Postponement in the continuous manufacturing enterprises and enriches the content of the quantitative research on the Postponement.

In this paper a comparison is presented for different battery charging concepts of Automated Guided Vehicle (AGV) systems using simulation models. In the focus of our investigation was, what kind of benefits can Inductive Power Transfer (IPT) for an AGV-based material handling system have, which is increasingly applied today. The proper application of IPT systems lets the reduction of the necessary number of AGVs and balances their utilization level.

For the sustainability of future logistics systems, Physical Internet is one of the most determined idea. Initial solutions and ideas exist, but the development in this area is far from complete. In our opinion, vehicle technology trends such as interconnected, autonomous vehicles and the platooning system are an important opportunity for the development of logistics network. This research aims to investigate how these new types of processes can be modelled using the results of a freight holding problem. The article surveys the possibility of reconfiguration of the platoons in the Physical Internet system by creating a virtual transfer point.

In our previous research, we have identified the components of the Physical Internet (PI, π) that are required to build and operate a Physical Internet based network. The components we defined include specific physical units, such as the π-container or the π-hub. In addition, components of management and information systems were included such as Open monitoring system or Track and Trace system. In this study we are exploring the feasibility of converting the established system of Physical Internet. Each component will be individually examined to find out which component is suitable for the PI network. The study discusses the applicability of existing intralogistics to a Physical Internet based network. In conclusion, we are exploring the possibility of future concepts for the intralogistics conversion of the Physical Internet.

Detection and pose estimation of pallets are critical phases in the operation of automated guided vehicles. In this paper, we introduce a novel pipeline for accurate localization based on only a single camera. We utilize the popular YOLO detector, object, and camera models to achieve better performance than the state of the art techniques.

The process description languages are used in the business may be useful in the optimization of logistics processes too. The process description languages would be the obvious solution for process control, to handle the main sources of faults and to give a correct list of what to do during the logistics process. Related to this, firstly, the paper presents the main features of the frequent process description languages. The following section describes the currently most used process modelling languages, in the areas of production and construction logistics. In addition, the paper gives some examples of logistics simulation, as another very important field of logistics system modelling. The main edification of the paper, the logistics simulation supported by process description languages. The paper gives a comparison of a Petri net formal representation and a Simul8 model, through a construction logistics model, as the major contribution of the research.

Construction processes can be implemented in most cases using various sorts of equipment. These can move along various paths, over the construction site from one job to another or during their operation. The proper choice of their path is a basic aspect for the planning of optimal processes. This paper is devoted to this problem. First it surveys some useful methods of path planning from the literature. Then it compares the methods considering construction specialties and finally it presents the developed intelligent system.

This paper presents the development of a new construction logistics model with a new point of view: we want to integrate related experiences from the practice of other industries with the specialties of construction logistics processes. It gives a detailed description on the proposed model. Furthermore, the basics of a demonstration physical test system will be described as well. The development introduced in this paper is a part of a Hungarian Government-financed research project (reference no. KTIA_AIK_12-1-2013-0009). The whole budget (c.a. 1.36 Million EUR) of the research is provided by the KTIA fund.

Application of agent based approaches is frequent in systems with artificial intelligence. This method has been used in simulations as well, however application in this field is rather novel. The paper surveys formation possibilities of agent based structures in the simulation of an example material flow systems. Further, considerations are also presented, how these models can be made adaptive, which makes them capable of continuously modify their features to the modeled physical system. Finally a framework for a proposed modeling problem is introduced.

Nowadays, modern companies operate in a common logistics network. In a modern approach, these networks of companies are called virtual enterprises, whose main purpose is the maximal fulfillment of customer needs and process optimization. The electronic freight and warehouse exchange is a good basis for building virtual enterprises, and that may be a new way to support the reorganization of the supply chains, and to rethink the connections within the intermodal network. Firstly, the paper presents the need of intermodality. On the other hand, it details the benefits and the critical evaluation of intermodality. It presents the general transshipment processes and techniques then evaluates the containers based on their main features. On this basis, the paper describes the electronic freight and warehouse exchange as a member of cloud supply chain. Moreover, the paper contains the new challenges and opportunities of electronic freight and warehouse exchanges as complex logistics providers.

Automated guided vehicles’ application in production facilities increases continuously. As these vehicles count as the industrialized version of mobile robots, the later ones can be regarded as the future of industrial AGVs. One of the most important issue of mobile robots is sensors. Landbased mobile robots currently use sensors for general navigational purposes, identification and range finding. Current paper surveys mobile robots’ most common sensors pointing out a possible further development using a static camera.

The execution of construction projects such as a highway construction or the elevation of a new bridge is a complex, highly equipment-intensive process and are subject to many different uncertainties. This is very similar to the manufacturing execution level in production systems where predefined productions plans and schedules cannot be completely implemented due to unexpected internal and external changes and disturbances. Following this analogy, the paper proposes the application of a discrete-event simulation based method which was already applied in the decision-support for manufacturing control to develop the decision-support in the execution of a construction project where the effects of the deviation from the short-term schedule can be easily and quickly analyzed.

This paper presents a formated navigation based on the leader-follower approach. In this approach, the control law of the follower robot includes the states of the leader robot. This is a drawback for implementing the control laws on real mobile robots. To overcome this drawback, this paper proposes a new follower's control law, called the self-made follower input, in which the state of the leader robot is estimated by the relative equation between the leader and the follower robots in the discrete-time domain. On the other hand, a control law of the leader robot is designed with a chained system to track a given reference path. The effectiveness of the proposed techniques is demonstrated in numerical simulation.

Logistics Journal: Not reviewed, Vol. 2012, Iss. 01 - Simulation ist heute eine unentbehrliche Komponente bei der Planung und Analyse von modernen Materialflusssystemen. Ihr Nutzen hangt in hohem Mase davon ab, wie akkurat sie das physikalische System modellieren kann. In diesem Artikel wird ein Kamera-basiertes System vorgestellt, welches in bestimmten Einsatzfallen bei der Datensammlung behilflich sein kann. Vor- und Nachteile des Systems werden diskutiert und die Einsatzfalle abgegrenzt. Am Ende des Artikels wird das Kamera-basierte Datensammlungssystem an Beispielen verdeutlicht und es wird gezeigt, wie die Ergebnisse in Simulationsmodellen angewendet werden konnen.

This paper presents a formated navigation with obstacle avoidance in which a modified leader-follower technique is combined with reactive collision avoidance behaviors. This paper indicates a couple of problems in which the obstacle avoidance is embedded in formated navigation: one is the singularity of the leader robot on the tracking control and another is the avoidance behavior of the follower robot. This paper proposes techniques for solving them and demonstrates the effectiveness in simulation and experiment.

This paper presents a formation control of multiple mobile robots based on the leader-follower technique. The control law of the leader robot is designed to track a specified reference path under a nonholonomic constraint of wheeled mobile robots, while that of the follower robot is designed to follow the leader robot with keeping the specified relative distance and the specified relative angle. This paper proposes a modified follower's control law, called the self-made follower input, in which the control law of the follower robot is given by itself. The state of the leader robot is estimated by the relative relationships between the leader and the follower robot in the discrete-time domain. The effectiveness of the proposed technique is demonstrated in simulations on PC and an experiment using real mobile robots.

This paper presents a formated navigation based on the leader-follower approach. In this approach, the control law of the follower robot includes the states of the leader robot. This is a drawback for implementing the control laws on real mobile robots. To overcome this drawback, this paper proposes a new follower's control law, called the self-made follower input, in which the state of the leader robot is estimated by the relative equation between the leader and the follower robots in the discrete-time domain. On the other hand, a control law of the leader robot is designed with a chained system to track a given reference path. The effectiveness of the proposed techniques is demonstrated in numerical simulation.