Search Results (298)

Articulated vehicles are essential for global freight transportation but are highly susceptible to instability phenomena such as jackknifing, trailer sway, and rollover, particularly under high-speed or emergency maneuvers. These challenges become even more critical in the context of autonomous driving, where stability must be guaranteed without human intervention. Conventional systems like Electronic Stability Control (ESC) and Roll Stability Control (RSC) provide reactive interventions but lack predictive capability, while other advanced methods often address isolated objectives. To overcome these limitations, this paper proposes a Model Predictive Control (MPC)-based control strategy that integrates trajectory tracking, yaw stability, and longitudinal speed regulation within a unified optimization framework, using differential braking as the primary actuator. A dynamic model of a tractor–semitrailer combination was developed, and the proposed controller was validated through high-fidelity simulations under varying operating conditions, including speeds exceeding the critical threshold of 31.04 m/s. Results demonstrate that the MPC-based system effectively mitigates instability, reduces articulation angle and yaw rate deviations, and maintains accurate path tracking while proactively managing vehicle speed. These findings highlight MPC’s potential as a cornerstone technology for safe and reliable autonomous operation of articulated vehicles. Future work will focus on experimental validation and multi-actuator coordination to further enhance performance. Full article

The accurate simulative reconstruction of blind spot accidents requires innovative simulation methods. The objective of this paper is to analyze the avoidability of a specific blind spot accident and assess the impact of various parameters as if an active turning assistant had been installed in the truck. Additionally, it proposes a novel adaptation of the turning assistant system, along with an adapted simulation model tailored for drawbar trailers. The analyses presented in this paper were performed using PC-Crash accident simulation software, applying the “Active Safety” module. After performing a simulation of an accident involving a right-turning truck with a center axle trailer and a pedestrian, the avoidability of the accident was examined by simulating the scenario as if the truck involved in the accident had been equipped with an active turning assistant system. Subsequently, a parameter analysis was conducted to analyze the effect of changes in the active turning assistant’s parameters and changes in the pedestrian’s direction of entry on the avoidability of the accident. In doing so, we determined the parameters for the worst-case (collision) and the best-case (no collision) scenarios. Finally, an adaptation and further development of the active turning assistant, along with a corresponding simulation method for drawbar trailers, are proposed. Full article

In response to new and emerging challenges in animal transport, including more stringent biosecurity and public demand for enhanced animal welfare, an innovative prototype trailer with mechanical ventilation and air filtration systems was developed. The performance of the trailer in maintaining acceptable environmental conditions for the pigs during transport in both cold and warm weather was evaluated through a series of road tests. In these tests, the general welfare of the animals during transport was also assessed. Results showed that temperatures inside the animal compartment during cold ambient conditions were above 10 °C for more than 60 to 90% of the trip despite the frequent occurrence of cold temperatures (below 0 °C) at the inlet. On the other hand, the temperature in the animal compartment ranged from 16 to 19.4 °C most of the time during transport in warm weather. The average moisture levels in the animal compartment ranged from 4.15 to 6.3 g/kg dry air and 5.05 to 78.8 g/kg dry air during cold and warm transport conditions, respectively, which is comparable to the humidity ratios measured in conventional pig transport trailers. Carbon dioxide concentration inside the animal compartment ranged from 912 to 1192 ppm in cold conditions and from 1008 to 1414 ppm in warm weather, indicating good air quality in the trailer during transport. Furthermore, there was no significant change in the levels of blood cortisol and in the rectal and body temperatures of pigs measured at the start and end of each monitoring trip, indicating that the pigs showed reduced or minimal stress during transport. The study demonstrated that the trailer design with a mechanical ventilation system significantly improved the thermal comfort and environmental conditions for pigs, contributing to their welfare during transport. Full article

Poultry transport represents a significant animal welfare challenge, particularly when birds are exposed to heat stress during travel, a condition that can compromise physiological stability, performance, and survival. Despite the relevance of this issue, research on engineering improvements to poultry transport crates remains limited. In this study, four virtual models of poultry transport crates were evaluated to assess their potential to improve the thermal comfort internal airflow conditions. Computational Fluid Dynamics (CFD) simulations were conducted under three transport speeds, complemented by wind tunnel experiments using reduced-scale prototypes fabricated by additive manufacturing. The results demonstrated that the alternative crate 3 (AC3) model presented exhibited superior internal average airflow velocities (IAFV) across all speeds, including a 32.85% increase compared to the conventional crate at 60 km/h. Wind tunnel testing confirmed significant differences among crate designs. AC3 showed lower air temperature than AC1 and reduced relative humidity compared to CC and AC2. Thermal comfort indices supported these findings, with AC3 presenting the lowest THI and enthalpy, indicating a less stressful microclimate. In terms of airflow, AC2 and AC3 achieved higher IAFV (19.27 ± 8.49 m/s and 19.30 ± 4.80 m/s) than CC and AC1. AC3 also had the lowest dynamic pressure, suggesting reduced airflow resistance and more efficient aerodynamics. Therefore, improved crate geometry and increased ventilation surface can enhance airflow distribution, potentially reduce heat accumulation and improve animal welfare. However, further studies involving live birds, realistic stocking densities, and full-scale trailer simulations are required to validate these benefits under commercial transport conditions. Full article

A promising approach to advancing sustainable urban mobility is the increased use of light electric vehicles, such as e-cycles and their cargo-carrying variants: e-cargo cycles. These micromobility vehicles fall between e-cycles and conventional vehicles in terms of transport capacity, range, and cost. A key advantage of e-cargo cycles over their non-electrified counterparts is the electric powertrain, which enables them to carry heavier payloads, travel longer distances, and reduce driver fatigue. Since the primary use of e-cargo cycles is urban parchment deliveries, trip efficiency plays a critical role in their effectiveness within urban logistics. This efficiency is influenced by factors such as travel distance, traffic density, and the weight and volume of the delivery payload. While higher delivery capacity generally enhances efficiency, studies have shown that as the drop size increases, the efficiency of e-cargo cycle delivery trips tends to decline. A practical way to address this limitation is the use of cargo attachments, such as trailers. These micromobility solutions are already widely implemented globally and significantly enhance transport capacity. This paper reports the process of designing and testing the control algorithm of an electrical system for an experimental attachment demonstrator that can be used to convert most cycle vehicles into cargo variants. The system integrates two 250 W BLDC hub motors, two 576 Wh lithium-ion batteries, dual load-cell sensing in the coupling element, and an STM32-based controller to provide independent propulsion and synchronization with the leading cycle. The force-based control strategy enables automatic adaptation to varying payloads typically encountered in urban logistics, which is supported by the variable storage volume capable of transporting payloads of up to 200 kg. Full article

Current research on the performance and emissions of vehicles and internal combustion engines should include analysis of efficiency-enhancing technologies and emission reduction strategies across a variety of vehicle systems. To improve both performance and emission control, it is necessary to examine advanced heavy-duty driveline technologies, considering their real-world impact on fuel economy and emission reduction under various driving conditions. This article will deal with predictive cruise control (PCC) and its influence on the operating characteristics of a truck, specifically a semi-trailer combination. The measurement was carried out using dynamic driving tests of a truck on a selected road. The use of electronic systems for automatically maintaining the vehicle’s motion states (especially speed) based on the specified conditions most often has several benefits for the driver not only from the point of view of vehicle operation but also from the point of view of transport companies (cost reduction). It is generally known that the use of these electronic systems reduces the vehicle’s fuel consumption and therefore also reduces the amount of exhaust gases. Comparing the individual directions of the road tests, the difference in relative maximum power utilization between the driver and the PCC system was 26.42% in the ST-MY direction and 23.81% in the MY-ST direction. The use of PCC also results in fuel savings of up to 17.11%. This study provides new insights into the quantification of the impact of PCC on fuel consumption in real operating conditions and highlights the potential for integrating PCC into driver assistance systems and logistics planning to reduce costs and emissions in freight transport. Further research could focus on applying this system in specific road conditions. Full article

Concepts such as reuse, repurposing, upcycling, remanufacturing, and re-powering can be applied to the reuse of combustion engines from passenger cars and trucks in stationary or mobile machines, such as power generators. Technical, economic, environmental, and research analyses indicate that such solutions may be justified; however, their implementation is limited by homologation and emission regulations. In most countries, there are no specific rules governing emissions from power generator engines, while in the European Union, such engines are categorized as mobile generators (portable or trailer-mounted) subject to Stage V (Reg. 2016/1628/EU), stationary generators (permanently installed) subject to the MCP Directive (2015/2193/EU), and emergency generators (limited operation) partially exempt from MCP but requiring registration. Consequently, engines recovered from road vehicles do not meet formal or technical emission compliance requirements for power generators and can only be used under conditional approval for research, experimental, or temporary purposes. This reveals a paradox of modern environmental policy: although reusing functional engines from dismantled vehicles could embody the principles of a circular economy, restrictive emission standards (Stage V, MCP, NSPS) effectively prevent such technological recycling. Addressing this issue requires legislative action and the development of simplified testing methods for used engines in new applications. This article is the first to systematically demonstrate that current Stage V, MCP and NSPS emission frameworks create a regulatory paradox that prevents the circular-economy reuse of functional automotive engines, and it proposes a dedicated secondary type-approval pathway enabling their legal and environmentally controlled application in power generators. Full article

Heavy vehicles present high aerodynamic drag. This results in significant fuel consumption and, consequently, high emissions of harmful substances. This study examines the variation in aerodynamic drag in a European-type truck with different trailer configurations. Passive flow control by geometry modifications of the rear part of the trailer and active flow control using the Coanda effect were tested, with the aim of improving the aerodynamic efficiency of the vehicle. To achieve this, a modular structure of a 1:30 scaled truck was designed to enable different trailer configurations. Drag measurements were performed with a two-component external balance, and PIV tests were conducted to correlate the drag reduction with the aerodynamic changes behind the trailer. Passive control reduced drag by up to 5.7%, and active flow control reduced it by up to 12.6% compared to the unmodified base trailer. PIV flow visualization confirms that blowing effectively reduces the recirculation zone behind the trailer. Full article

Operation of vehicle–trailer combinations is currently popular throughout many countries. Connecting a trailer to a passenger car increases the car’s utility value because it is possible to transport more goods over shorter or longer distances. Trailers are also popular as caravans, which provide a home on wheels during holiday periods. As a trailer is connected to a towing vehicle by means of a spherical joint from the mechanics’ point of view, a vehicle–trailer combination has significantly different driving properties in comparison with a sole vehicle. These differences are manifested mainly while driving in a curve as lower stability of the vehicle. In this case, the lower stability is considered an uncontrolled sway motion. This study is focused on researching the driving stability of a vehicle–trailer combination regarding the sway motion problem. The research is fully performed by means of simulation computations in a commercial multibody simulation software. The investigated vehicle–trailer combination consists of an SUV passenger car and a single-axle goods trailer. Two model driving maneuvers are investigated, namely bypassing an obstacle in a lane and changing lanes on a road. Simulation computations are performed for chosen loads of the trailer and for a different position of the center of gravity of the load in the single-axle trailer. The performed research has proven that the applied simulation computations represent a robust tool to investigate real tasks related to vehicle safety without performing expensive and dangerous tests. Very important findings include identifying the proper position of the center of gravity of the load on the trailer to ensure safe driving properties for driving maneuvers that could pose potential danger during real operation. Full article

In vehicle routing problems, long-distance transportation poses a significant challenge to the optimization of transportation costs while adhering to regulations. This study investigates a special type of logistics problem that focuses on liquid transportation systems involving full truckload delivery and the rest–break–drive periods of truck drivers over long distances according to the regulations of the United States. Based on an exact solution algorithm, this work combines a long-distance full truckload fluid transportation problem with the concept of truck driver schedules for the first time. The goal is to optimize transportation expenses while managing challenges related to the rest–break–drive periods of truck drivers, time windows, trailer varieties, customer segments, food and non-food products, a diverse fleet, starting locations, and the diverse tasks of vehicles. In order to reach optimality, a construction heuristic and the column generation method were employed, supplemented by several acceleration strategies. Performance analysis, carried out with artificial input sets mirroring real-life scenarios, indicates that low optimality gaps can be obtained in an appropriate amount of time for large-scale long-haul liquid transportation. Full article

Cross-docking has emerged as a critical logistics strategy to reduce lead times, lower inventory levels, and enhance supply chain responsiveness. However, in high-throughput terminals, efficient coordination of inbound and outbound trailers remains a complex task, especially under uncertain and dynamically changing conditions. We propose a practical framework that helps logistics terminals assign trailers to docks in real time. It links live sensor data with a mathematical optimization model, so that the system can quickly adjust trailer plans when traffic or workload changes. Real-time data from IoT sensors, GPS, and operational records are preprocessed, enriched with predictive analytics, and used as input for a Mixed-Integer Linear Programming (MILP) model solved in rolling horizons. This enables the continuous reallocation of inbound and outbound trailers, ensuring synchronized flows and balanced dock utilization. Numerical experiments compare the adaptive approach with conventional first-come-first-served scheduling. Results show that average inbound dock utilization improves from 68% to 71%, while the share of periods with full utilization increases from 33.3% to 41.4%. Outbound utilization also rises from 57% to 62%. Moreover, trailer delays are significantly reduced, and the overall makespan shortens from 45 to 40 time slots. These findings confirm that adaptive, real-time trailer assignment can enhance efficiency, reliability, and resilience in cross-docking operations. The proposed framework thus bridges the gap between static optimization models and the operational requirements of modern, high-throughput logistics hubs. Full article

In line with EU decarbonization targets for the heavy-duty transport sector, this study proposes an analytical methodology to assess the impact of diesel performance additives on fuel consumption in Euro 6 heavy-duty vehicles, the prevailing standard in the circulating European road tractor fleet. A fleet of five N3-category road tractors equipped with tanker semi-trailers was monitored over two phases. During the first 10-month baseline phase, the vehicles operated with standard EN 590 diesel (containing 6–7% FAME); in the second phase, they used a commercially available premium diesel containing performance-enhancing additives. Fuel consumption and route data were collected using a GPS-based system interfaced with the engine control unit via the OBD port and integrated with the fleet tracking platform. After applying data filtering to exclude low-quality or non-representative trips, a 1% reduction in fuel consumption was observed with the use of fuel with additives. Route-level analysis revealed higher savings (up to 5.1%) in high-load operating conditions, while most trips showed improvements between −1.6% and −3.4%. Temporal analysis confirmed the general trend across varying vehicle usage patterns. Aggregated fleet-level data proved to be the most robust approach to mitigate statistical variability. To evaluate the potential impact at scale, a European scenario was developed: a 1% reduction in fuel consumption across the 6.75 million heavy-duty vehicles in the EU could yield annual savings of 2 billion liters of diesel and avoid approximately 6 million tons of CO₂ emissions. Even partial adoption could lead to meaningful environmental benefits. Alongside emissions reductions, fuel additives also offer economic value by lowering operating costs, improving engine efficiency, and reducing maintenance needs. Full article

Lithium-ion battery (LIB) wireless charging using inductive power transfer (IPT) represents a transformative pathway for transportation electrification. While applications in railway systems remain limited, early studies highlight significant promises for implementation. This paper presents a hybrid energy-supply framework integrating LIB, inductive battery charging (BC) charging, and battery swapping (BS) to support a 20 km heritage trolley excursion between Belmont and Gastonia, NC. A kinematic simulation was developed to estimate traction energy demand, yielding 56 kWh per trip, or 112 kWh for two daily round trips. Finite element analysis (FEA) was conducted to design an LCL-s compensated 3 kW IPT system. Two transmitter configurations were evaluated: W–I ferrite cores (peak coupling ~0.22) and magnetic concrete slabs (~0.20). Although ferrite offers higher efficiency, magnetic concrete demonstrates superior durability and integration potential. Simulation results indicate that wireless charging alone, whether static or dynamic, is insufficient; similarly, a single daily BS strategy provides only 96 kWh. Seven BC-BS hybridization scenarios were evaluated, showing that mid-day swaps combined with either static or dynamic IPT produce a 12–16 kWh surplus. The most practical approach is a one-pack swap supplemented by uniformly distributed static pads, providing energy neutrality. This hybrid pathway ensures operational sufficiency, structural resilience, and compatibility with heritage rail preservation. Full article

In order to investigate the influence of different tire textures, pavement types, and vehicle parameters on the tire/road noise level and its spectrum characteristics, 19 kinds of asphalt pavement main structures of RIOHTrack full-scale test track were tested by the close-proximity trailer (CPXT) tire/road noise detection method. Considering investigated parameters such as tire texture, vehicle speed, and trailer axle weight, and relying on multi-functional road condition rapid detection vehicle and laboratory tests to collect a variety of road surface information and material parameters, a multiple-linear-regression model of tire/road surface noise level of RIOHTrack (Research Institute of Highway Full-scale Test Track) asphalt pavement was constructed. Finally, the causes of noise level differences among different influencing factors were further analyzed through spectrum characteristics. The results show that vehicle speed is the most important factor affecting tire/road noise. The noise level of different tires varies due to different textures, but the noise level among different trailer axle weights is roughly the same. Vehicle speed (v), FWD center deflection (D₀), surface asphalt mixture air voids (VV), sensor-measured texture depth (SMTD) and international roughness index (IRI) were selected to establish the noise prediction models of different tire textures. Noise spectrum analysis shows that the spectrum of different vehicle speeds is significantly wide in the full frequency range, and the spectrum variation of differently textured tires is mainly concentrated in a certain range of the peak frequency. The noise spectrum curve of porous asphalt concrete (PAC13) is significantly lower than that of other asphalt mixtures in the full frequency range above 800Hz, indicating a greater noise reduction effect. Full article

Trailers for passenger cars are often used for the transportation of goods. There are various trailer designs. Most trailers are equipped with axles, which include swinging arms and are suspended by rubber segments. Observations have revealed that empty trailers have unfavorable driving properties when they are driven on uneven roads, for example, the wheels could jump off the road. Such a situation is dangerous because it is not possible to transmit any contact forces (longitudinal, lateral, or vertical) between the wheel and the road. The goal of the present research was to measure acceleration generated in a single-axle trailer when driving over a road obstacle. Measurements were conducted in a non-public area to avoid the risk of accidents. Acceleration was recorded using two accelerometers placed on the single-axle trailer frame above the wheels’ axle of rotation. Tests were performed using a vehicle–trailer combination at the chosen driving speeds, and the results for driving speeds of 20 and 30 km/h are presented. Wood plates with a height of 25 and 50 mm were used as an artificial road obstacle. The single-axle trailer was loaded with gravel bags weighing 0 to 300 kg. The measurements revealed that heavier trailer loads and lower driving speeds are safer for trailer operation. Furthermore, the measurements also demonstrated that the wheels were significantly more likely to jump off the road with a 0 kg load and low driving speed. Full article