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The movement of the car in the traffic on intercity routes was investigated. Traffic should be energy efficient, safe and comply with the desired schedule. A method for analyzing the input data flow based on a simulation model has been developed. The proposed simulation algorithm is based on the use of available information resources for driving a car. Traffic control involves choosing a speed with known road and traffic restrictions. The presented algorithm allows to consider the expediency of each of speed increase opportunities over the forecast horizon. The content of the algorithm is the optimal redistribution of time resources. Indicators of control quality are absolute deviations from the optimal energy-saving program of free movement and from the planned schedule. The movement of a freight road train on the long-distance highway E−371 was performed. It was found that the total amount of information increases with increasing distance of scanned traffic. However, the share of reliable information is reduced. It was found that the dependence of the quality of vehicle traffic control on the size of the forecast horizon is piecewise-continuous. The dependence has an extreme value of the horizon in each continuous section, at which the deviation from the optimal program is minimal. The obtained results can be applied in modern intelligent transport systems. The research results make it possible to develop and adhere to optimal long-term traffic programs on highways. It solves the problem of managing large data streams. Large amounts of information for forecasting can be submitted in parts with reasonable frequency using the developed methodology

The object of the study is the production and technological processes of international road transport (PTP IRT) according to the innovative approach and the conceptual idea of technical and technological energy saving in motor transport. Predictive assumptions about the development of the object of study–the realization of the possibilities of operational-simulation and technical-evolutionary method of complex analysis of transport energy efficiency of road trains and production and technological processes of international road transport in the practice of international road transport. In the course of the research the operational-simulation and technical-evolutionary method of complex analysis of transport energy efficiency of road trains and production-technological processes of international road transportations was considered.As an example, the influence of changes in such a design parameter of the road train as the gear ratio of the main transmission of the tractor on its transport energy efficiency, as well as fuel and energy consumption of the road train DAF FT95.360 (Netherlands) in the test trunk operation (atαg=0). It is established that when the value of the gear ratio of the main transmission (Uo) increases, the value of the energy efficiency indicator (Pe) varies from 0.55 to 0.58. The greatest value of energy efficiency is atUo=2.846. It is determined that when the value of the gear ratio of the main transmission (Uo) increases, the value of the energy consumption indicator (Ac) increases, and the minimum value of 3.2 MJ acquires the value of the gear ratio of the main transmission – 2.846.It was found that when the value of the gear ratio of the main gear (Uo)increases the fuel consumption (Qc) increases and acquires a maximum value of 3496.84 g with the value of the gear ratio of the main gear–4.39. The minimum value of fuel consumption of 1684.2 g is achieved when the value of the gear ratio of the main transmission 2.846. The results of the study can be used to implement systemic and conceptual innovation management in the field of international road transport.

The article discusses the influence of the road longitudinal slope on variation in reaction forces on the wheels of the road train. The description of the longitudinal slope of the road and methods of its determination are given. The design diagram of the forces and moments acting on the road train during its movement uphill and downhill is presented. Equations for calculating the change in the load on the three axles of the road train, depending on the longitudinal slope of the road and the mode of movement, are presented. Based on the calculation results, graphs were constructed to illustrate the change in loads on three axles of the road train. The results show that the changes in the normal reactions on the front axle of the road train are significant, affecting the braking properties and driving safety of the vehicle. The scheme for calculating the variation in loads on the axles of a road train can be used to automatically adjust the braking forces between the wheels depending on the loads and thereby ensure traffic safety.

The paper is devoted to the problem of optimization of transport tasks’ execution schedule. The exploitation of a group of interdependent highway road trains is considered. The task differs from the known ones by limitations of the duration of a cycle within which a maximum number of goods transportation orders must be fulfilled. There are also limited intervals of time when loading and unloading of vehicles is permitted at appropriate points of a transport network. The solution of the problem consists in distributing a given number of road trains between orders, finding the shortest path for each of them, and determining the time of their departure and arrival provided the absence of idle runs and with minimal time delays of the process. It is shown that a maximum number of completed tasks are proportional to the duration of the cycle up to a certain limit only. The optimization is carried out for two options: in the absence and presence of restrictions on repeatability of freight flows from one point. The used algorithm guarantees an exact solution for an acceptable period of time for a small-dimensional task.

In work the estimation and a choice of log trucks for the certain technology of export of assortments on technical and economic criteria is considered. The considered algorithm includes the formation of requirements for cars -sortiment trucks from the road transport organizations, the choice of cars present in the market, the calculation of their economic efficiency, the definition of integrated quality indicators and the final choice of the car brand. As a result, the most efficient sorting vehicle is chosen for the selected timber transportation segment and the fleet of the trucking organization is formed, depending on the volume of transportation. The offered technique can be used at formation of a cargo vehicle fleet of any enterprise, its updating, and also at the organization of transportations with a view of fastening of concrete cars behind certain routes.

This article explores decision analysis regarding Drop and Hook (D&H) transportation operations at sugarcane mills. By means of a case study, a combination of a discrete event simulation model and multi-attribute utility theory was used to evaluate different configurations for sugarcane delivery systems using internal, external, or no D&H systems. A D&H strategy maximises truck utilisation, as semi-trailers can be handled independently of the traction unit of the trucks, which makes the transport system more agile. For internal D&H systems the semi-trailer detaching/attaching point is located inside the mill site while for external D&H systems it is located outside, before the trucks’ weighbridge. Each configuration requires different infrastructure which affects the supply of sugarcane for milling. The case study was applied to a sugarcane mill of a corporation located in São Paulo State. By means of discrete simulation, we determined that eighteen D&H configurations were feasible. By using the swing weighting multi-criteria decision analysis (MCDA) method, we identified fleet cost as the most important factor, while configurations with external D&H systems showed the best utility values. For this case study, the best configuration is to use the external D&H strategy with 28 road trains (truck and two semi-trailers), 12 additional semi-trailer sets, and 6 tractor units.

International audience; This paper deals with the stable navigation of up to eight articulated vehicles, coupled together to form a road-train. Based on kinematic and dynamic models, three control approaches are proposed for dynamic stabilization in road-train configuration, as well as a methodology for setting control gains, using three possible actuators: damper at the vehicle articulation, front steering or rear drive wheels. Implementation on a 3D simulator, representative of the dynamics of the real system with a high degree of fidelity, demonstrates the controller's performance and robustness in critical scenario conditions. Tests are then conducted in real conditions to validate the new strategy.

The peculiarities of organization and perspectives of mass passenger transportation in the city and beyond are considered with the use of "Bus Rapid Transport" (BRT) or Metrobus. Different aspects of study of motor vehicles (MV) controllability and stability are analyzed. It is substantiated that it is sufficient to consider the potential stability of the MV itself, in order to guarantee the stability of the "driver - MV" system with a large reserve. A mathematical model of a three-axle bus train consisting of a bus and two trains (metrobus) is developed and the factors influencing the critical speed as the main index of the stability of its movement are determined. It is established that the increase of the critical speed of the metrobus can be achieved by increasing the base of the bus, the first and the second trailer, as well as the mass of the bus and the coefficients of resistance of the drive wheels of the bus driving axle and the trailers axles. At the same time, increasing the distance from the mass center to the bus rear axle, increasing the distance from the mass center to the point of the coupling of the bus with the first trailer, increasing the mass of trailers and the resistance of the resistance of the wheel drive of the bus axis lead to a decrease in the critical speed of the metrobus. This must be taken into account both when designing metrobuses, and when operating them. Keywords: bus train, metrobus, movement stability.

Intelligent transportation systems and the advent of smart cities have created a renewed research interest in vehicular networks (VANET). These ad-hoc networks are the key technology for new collaborative approaches to increase the efficiency and safety of our roads. In effect, city-scale field trials are being conducted by major high-tech companies to explore the capabilities and limitations of vehicle-to-infrastructure and vehicle-to-vehicle communication. Initial advances have led to safety enhancing applications like the electronic emergency brake light, cooperative collision avoidance and cooperative adaptive cruise control. In IEEE standard 1609.2, security measures to guarantee the integrity and authenticity of VANET messages are specified. However, physical properties like spatial proximity and driving direction are not considered. These become notably important when vehicles make decisions that concern the safety of users for example to avoid a collision. We propose a novel approach to verify the ongoing copresence of two vehicles. Our method is based on the observation that the trajectory through a road network can be used to uniquely define a vehicle's location as well as its driving direction. Our system provides a protocol to authenticate VANET messages for a group of vehicles driving in succession and to de-authenticate vehicles that have left the formation. To demonstrate the feasibility of trajectories as proof for co-presence, we implemented a smartphone application and conducted driving experiments under real-world conditions. We analyze the road network of several major cities from different continents to show the generalizability of our approach. Additionally, we systematically evaluate the security properties of our system by performing city-scale simulations under realistic conditions.

Mathematical models of a road train are developed to study both its direct and reverse motion. The laws for the automatic steering system turning vehicle steering wheels to achieve the required trailer direction when moving reverse are synthesized. A road train with a hitching unit on the tractor truck rear axle directly schematic constructions (an “on-axle hitching” model) are used. The kind of kinematic mathematic model for describing a road train moving reverse at low speeds without wheels side slipping is satisfactory. In this condition its motion is defined by geometry only independent from masses, momentums and friction forces. The steering laws are synthesized with the help of alpha-stabilizing approach, according to Lyapunov’s direct method using fuzzy logics mathematical tool and a solution method depending on the Riccati equation state (SDRE). The task of reaching a set goal has been solved by calculating the folding angle when the target belongs to the calculated path for the case of curvilinear motion and via calculating the matching tractor truck and trailer orientation angles for direct motion. The received results have been rendered as phase portraits in the Maple environment and meshes in Meshlab, simulated in Unity 3D and with a robotic installation getting control information generated automatically

Accurate prediction of traffic information is important in many applications in relation to Intelligent Transport systems (ITS), since it reduces the uncertainty of future traffic states and improves traffic mobility. There is a lot of research done in the field of traffic information predictions such as speed, flow and travel time. The most important research was done in the domain of cooperative intelligent transport system (C-ITS). The goal of this paper is to introduce the novel cooperation behaviour profile prediction through the example of flexible Road Trains useful road cooperation parameter, which contributes to the improvement of traffic mobility in Intelligent Transportation Systems. This paper presents an approach towards the control and cooperation behaviour modelling of vehicles in the flexible Road Train based on hybrid automaton and neuro-fuzzy (ANFIS) prediction of cooperation profile of the flexible Road Train. Hybrid automaton takes into account complex dynamics of each vehicle as well as discrete cooperation approach. The ANFIS is a particular class of the ANN family with attractive estimation and learning potentials. In order to provide statistical analysis, RMSE (root mean square error), coefficient of determination (R2) and Pearson coefficient (r), were utilized. The study results suggest that ANFIS would be an efficient soft computing methodology, which could offer precise predictions of cooperative interactions between vehicles in Road Train, which is useful for prediction mobility in Intelligent Transport systems.

W artykule opracowano sposób poprawy manewrowości pojazdu za pomocą blokowania kąta łamania. Opisany model umożliwia dokładne przeanalizowanie ruchu ciągnika siodłowego. Zaproponowano oprogramowanie do kontroli ruchu dwuosiowego obiektu przy obciążeniu. Stworzono algorytm sterowania podstawowymi mechanizmami danego obiektu, tak aby zapewnić stabilność ruchu. Pokazano niektóre z istniejących mechanizmów sterowania naczepami oraz zaproponowano nową konstrukcję, która pomaga sterować zestawem siodłowym podczas cofania.

The main task of this paper is to review the principal aspects in organization of interurban long haul service by use of road trains on the basis of the “district” traffic system. The goal of the paper is to determine the most effective methods of trucking operations in order to highlight the regularities that characterize these methods. The paper describes practicable methods of freight flow analysis, some factors and parameters concerning movement of motor‐vehicle trains and original route schedules as well. Of special interest is the obtained algorithm of economically effective trucking operations of motor‐vehicle trains on the route. First Published Online: 27 Oct 2010

To analyze the influence of structure type on passing ability of car transport vehicle combination, the four basic vehicle combination models of two typical structure types, such as car transport semi-trailer road train and car transport vehicle combination with center axle trailer, have been built by using TruckSim. The turning circle test and the adaptability test on highway have been simulated on dry pavement to analyze the relationship between the structure type and the turning passing ability. The results show that the structure parameters have significant influence on the passing ability of car transport vehicle combination; three of the vehicle combination models can meet the requirements of GB 1589-2004“Limits of dimensions, axle load and masses for road vehicles”; all the four basic vehicle combination models will take up the lane beside itself when running on the up to and including third-grade highway/ramp.

In many parts of the world the freight transport task is primarily undertaken on public roads. The exact share is heavily influenced by the presence of other transport modes (railway, inland waterways) and the topography of the country, and for these reasons the share of road transport varies from approximately 35% (Australia) to over 70% (European Union). Worldwide, there are various regulations regarding the weights and dimensions (and accordingly, axle loads) for heavy vehicles, and as a result, the heavy vehicle industry has developed a range of transport solutions in response, leading to a wide range of vehicle combinations which vary in their design and specification. In 2010, the Joint OECD/ITF transport research Centre (JTRC) working group selected 38 different heavy vehicle combinations from OECD member states, and studied their performance in order to gain an understanding of the influence of their individual characteristics in three key areas; the vehicle's inherent safety, its productivity, and its impacts on infrastructure [5] . Vehicle productivity was described using various metrics involving cargo weight and volume, energy consumption, and travel distance. Higher loading capacity and utilization (lower tare mass), and lower fuel consumption (low rolling and air resistance) can increase the efficiency as much as possible for a given travel speed and distance. Inherent vehicle safety and dynamic performance in various driving maneuvers was addressed using computer simulation, conducted in accordance with the Australian ‘Performance Based Standards’ scheme. Vehicle infrastructure performance was calculated on the basis of axle loads, tyre type and size, as per the ‘COST 334’ vehicle road wear performance analysis method. This paper presents and discusses the results demonstrated by ten of the vehicles investigated in the OECD study. Nine out of ten vehicles represent current and possible future freight vehicles for Europe, and were selected because they have particular relevance given the current debate in Europe on increased masses and weights of freight vehicles. Further, one Australian ‘road train’ vehicle was included, as it represents one of the longest and heaviest vehicle combinations permitted access throughout the world, and is useful for comparative purposes.