Semi-trailer Truck Research Articles

Dynamic interaction of the piggyback platform And semi-trailer truck

The article presents a mathematical model of joint oscillations of the car-platform for piggyback transportations and semi-trailer truck. Considered forced oscillations of the investigated object in the vertical plane of symmetry. Built a design scheme of the platform with mounted on it with a tractor and trailer system are presented in the form of a mechanical system, all bodies which, in addition platform, accept hard. The supporting structure of the platform is presented in the form of elastic massless beams carries seven lumped masses. A railway track is considered inertial with elastic-dissipative properties. In the simulation work for suspension updated power characteristic of the friction damper. As disturbances acting on the wheelset of the platform, considered butt roughness of the track. According to the results of computer simulation obtained measurements of vertical dynamics, piggyback platforms depending on the stiffness and characteristics of the oscillations damping. The obtained data dynamic calculations allowed us to estimate the schemes of fastening of a semi-trailer truck and to determine the influence on the dynamic indexes of changes in the stiffness of the spring suspension and the coefficient of friction relative to wedge the damper through adjustment of a spring set. Proved the feasibility of the decision on the free installation of the train on the platform, allowing automotive suspension gets the opportunity to actively damping the perturbations transmitted to the wheels of the road train from the platform.

The method of increasing the stability of trailer-trucks in case of emergency braking in a turn and emergency failure of the trailer brake system

One of the most important properties of semi-trailer trucks are stability and steerability. This is because with an increase in driving speeds, these properties largely determine the safety of vehicle operation. Improving the semi-trailer trucks safety is all the more relevant because the consequences of road accidents involving semi-trailer trucks are the most severe and cause enormous damage. One of the most common causes of accidents is the loss of stability during emergency braking in a turn, especially in the event of a failure of trailer braking system. The goal of this research is to develop principles for improving the stability of semi-trailer trucks movement during emergency braking in a turn and failure of trailer braking system. A method has been developed to increase semi-trailer trucks stability during emergency braking in a turn and the failure of trailer braking system, which allows to maintain the trajectory stability of the semi-trailer truck and to avoid accidents with severe consequences. Using simulation methods, the effectiveness of the proposed method is proved.

МЕТОДИКА СРАВНИТЕЛЬНОЙ ОЦЕНКИ ТЕХНИЧЕСКОГО УРОВНЯ САМОСВАЛОВ РАЗЛИЧНЫХ КОМПОНОВОЧНЫХ СХЕМ

Introduction : An analysis of the special-purpose road construction machinery market reveals an immensely diverse range of vehicles that can be used in construction. Due to this diversity, users may experience difficulties when choosing a dump truck from a range of vehicles with identical performance parameters. The final choice is often based on the user’s subjective preferences and not always logically justified. This calls for designing a methodology that would make the choice of dump truck model less biased. Purpose of the study: The study is aimed to create a range of research and methodological tools for facilitating the comparative assessment of construction dump trucks that belong to the same category in terms of load capacity, but differ by structure. Methods: We compared and assessed our samples by contrasting the generalized vehicle quality parameters, as reflected by their technical quality coefficient. As research methods for collecting reference data for our assessment, we used information search, statistical analysis of information sources, expert studies, and mathematical modeling. Results: The comparative qualimetric assessment of the technical quality of different dump truck designs has prompted a conclusion that, when it comes to road construction, semi-trailer trucks are more preferable than chassis-based trucks. Specifically, semi-trailer dump trucks are characterized by better sustained performance, maneuvering ability, and terrain crossing capacity. Conclusions: The proposed method of technical quality comparative assessment allows for a more unbiased choice of dump trucks for road construction, based on analyzing their most vital performance parameters.

Development of a Unified Lane-Keeping and Collision Avoidance System for Semi-Trailer Truck

In this article, a unified lane-keeping and forward collision avoidance system is proposed for semi-trailer trucks. Kinematic and dynamic models are described for lateral motion of the semi-trailer truck. The variation of the cornering stiffness is considered because its value depends on driving conditions such as vehicle speed and vertical load. The proposed system consists of the hitch angle estimation algorithm of the semi-trailer truck and the Model Predictive Controller (MPC) for the lateral motion of the semi-trailer truck. In the hitch angle estimation, the disturbance observer is utilized to compensate the lateral uncertainties and the estimation performance is validated in simulations and experiments. In the controller design, an MPC controller is designed both for lane keeping and collision avoidance, but their constraints in lateral motion are considered separately. In constructing the objective functions, constraint smoothing is applied to improve the feasibility of the semi-trailer truck motion. A simplification method is also introduced to reduce the computational complexity of the MPC and to improve the real-time performance. The proposed system is evaluated in simulations for lane keeping and collision avoidance, respectively.

Movement analysis of the semitrailer with the tank-container at hard braking -the case study

Transport of liquid, gaseous, powdered or granulated substances is an integral part of the industry in each country. This type of cargo is most often transported by companies that are a part of petrochemical, food or also other types of industry. Increased attention should be paid to transport of tank-vehicles and tank-containers from the point of view of road safety and environmental protection. The volume of such types of transport is growing every year. The extensive trend relates mainly to the developed world economies, which are experiencing economic growth, which includes also Slovakia according to the Statistical Office of the Slovak Republic. This article deals with evaluating the movement of semi-trailer trucks with a tank container during and immediately after hard braking. The movement of the semi-trailer truck with a tank container will be analysed and evaluated immediately after the vehicle is stopped. The movement of the vehicle will be analysed by video analysis. The focus is on analysing behaviour of the semi-trailer truck with a tank container during and immediately after braking. The article compares semi-trailer trucks with tank container with breakwater plates and tank containers without breakwater plates. An important feature of this comparison was processing of videos capturing these vehicles during hard braking in video analysis program.

A Drivetrain Integrated DC Fast Charger With Buck and Boost Functionality and Simultaneous Drive/Charge Capability

Electric vehicles have the potential to change the global driving paradigm, significantly reducing the environmental impact of transportation systems. However, charging infrastructure cost and range anxiety impose challenges on rapid technology adoption. This paper proposes an onboard integrated dc charger, leveraging the traction inverter, and motor winding inductance to ensure the minimum incremental mass. The proposed circuit allows the vehicle to connect directly to emerging dc microgrids, utility storage, or renewable energy resources. The system is compatible with power supply voltages higher or lower than the vehicle battery, offering the possibility to charge 400-V batteries from emerging 1000-V supplies, as well as 800-V battery from the existing 600-V dc interfaces. The presented method also provides bidirectional fault blocking capability and bidirectional power transfer, suitable for V2G, G2V, or V2V operation. In addition, this paper proposes simultaneous driving and charging, especially useful for semitrailer trucks applications, significantly increasing operational range. The solution presented in this paper offers a simple and safe charging scheme with the potential to substantially reduce charging infrastructure cost and address range anxiety.

The Analysis of Modified of Cakar Ayam (CAM) Designed with Concrete Plate Thickness Variation in Soft Soil

Modified of Cakar Ayam System (CAM) is a system that uses galvanized steel pipes as stiffener plate. This system had been implemented on the trial road of Pamanukan-Indramayu, Indonesia. Many advantages are obtained from the use of this system, for example reduction on deflection, durability, and application on road pavement. Full scale trials had been conducted in Indonesia, for the examples, the Waru-Surabaya Highway and Section IV Highway, Makassar. Despite this system is widely used but there are still many problems occur such as deflection and crack due to less plate thickness. This research will discuss about the deflection, moment and shear force of plate model on soft base ground using Finite Element Method (FEM). The system configurations for concrete plate applied in this research were 7.25 m in width and 14.0 m in length with thickness was varied by 0.15 m, 0.18 m and 0.22 m using 21 cakars. The loads represented semi-trailer truck loading with the weight of each axle propagated into 2 equal uniform loads. The position of test loading points were made in several variations to determine the largest deflection value. If the plate got thicker then, its stiffness value would increase and the deflection accorded smaller result. By using CAM System, cakar could function as a load restraint and plate grip. The stiffness of the plate would increase when the plate was applied with the CAM System and could reduce deflection by 2.74% to 39.77%. On the effect on the moment and shear force, it was found that the thicker the plate, the greater the moment and shear force value obtained. The difference in the value of the moment obtained from the comparison between the plate using the CAM System and the plate without the CAM System was 0.23% to 1.60%, while for shear force values, the difference was 7.56% to 11.19%.

Experimental Analysis on Effectiveness of Crash Beams for Impact Attenuation of Overheight Vehicle Collisions on Railroad Bridges

AbstractCollisions between overheight semitrailer trucks with low-clearance railroad bridges are one of the leading causes for railroad traffic interruptions on bridges in the United States. Curren...

Vibration Effect Produced by Raised Pavement Markers on the Exit Ramp of an Expressway

Driving over raised pavement markers (RPMs) spaced at different spacing, the human body will experience different vibrations. To explore whether RPMs situated at the exit ramp of an expressway induce a good vibration warning effect, this paper determines the spacing of RPMs situated along a deceleration lane and curved ramp. Models of roads, vehicles, and RPMs are first established in the ADAMS software, after which an integrated human-chair model constructed in SolidWorks is imported into ADAMS, and then the complete model is formed so that vibration simulations of different types of vehicle at different spacing and speeds can be carried out. The results show that the vibration warning effects of the spacing proposed by the existing Chinese specifications and this paper are basically between level III and level IV, the driver’s subjective feeling is between less comfortable and uncomfortable, and both induce a good vibration warning effect. For a linear deceleration lane, when considering traffic safety, a spacing of 3 m is recommended; when considering the economy, a spacing of 6 m is recommended. For a curved deceleration lane and curved ramp, according to the actual curve radius, the spacing of RPMs can refer to the spacing recommended in the paper. In addition, the vibration warning effect for cars and semi-trailer trucks initially increases with an increase in the speed; then, after reaching a certain peak speed, the effect decreases with an increase in the speed, and finally, it tends to become gentle at speeds exceeding 100 km/h. The vibration warning effect for a semi-trailer truck is better than that for a car under the same spacing and speed.

Accurate real-time truck simulation via semirecursive formulation and Adams–Bashforth–Moulton algorithm

In this paper, a tailored four-step Adams–Bashforth–Moulton (ABM) algorithm is applied to a semirecursive formulation to perform a real-time simulation of a semitrailer truck. In the ABM algorithm, each integration step involves two function evaluations, namely predictor and corrector. This is fundamentally different when compared to the classic fourth-order Runge–Kutta (RK) integrator approach that contains four function evaluations. A semitrailer truck under investigation is modeled in term of a semirecursive method and simulated by using the presented ABM algorithm. The results show that the four-step ABM method can reduce CPU time almost 50% for solving the truck dynamics with very similar accuracy, in comparison to the fourth-order RK method. The presented ABM algorithm could be used in the semirecursive formulation to carry out accurate real-time simulation of medium-large vehicle systems.

Monitoring of the technical condition of semi-trailer trucks

The article presents results of the reliability study of controlled groups of vehicles possessed by two road transport enterprises working in the international transport sector (truck tractors – VOLVO FH 1242Т – 50 unit and MERCEDES-BENZ 1844 ACTROS LS -100 units, semi-trailers SCHMITZ, KRONE and KÖGEL – 50 units from each of the semi-trailers company). Possibilities for reliability increasing and reduction of the maintenance and repair cost are defined. The results of the reliability evaluation of vehicles during three years of operation with a different annual run (from brand new up to 440·103 km, including warranty period) are presented. Based on the conducted studies of failures and details malfunctions, units and systems of the vehicles, the average operating time to failure or occurrence of malfunctioning, the probability of failure-free operation, and the time spent on repairs were determined. Asymmetric graphs of working capacity disturbance were obtained, which allowed determining the level of const uction design perfection, the technological accuracy of equipment assembly and the quality of fastening works. The inadequate adaptability to operate on the roads of the CIS was reflected by symmetric distribution laws. The least reliable aggregate and assembly elements were identified.

Two-echelon logistics delivery and pickup network optimization based on integrated cooperation and transportation fleet sharing

The optimization of the two-echelon logistics delivery and pickup network (2E-LDPN) is a strategical and tactical task which can efficiently be achieved by establishing cooperative alliances. Under the coordination of logistics services providers or logistics facilities of the existing network, high operating costs caused by cross and long distance transportation can be reduced via the inclusive reorganization of the entire network. In order to minimize the total cost, this study simultaneously considers semitrailer truck and vehicle sharing, and establishes a linear mathematical model capable of interpreting real world practices under single or multiple alliances scenarios. An Improved Particle Swarm Optimization (IPSO) algorithm and the Ant Colony Optimization (ACO) algorithm are reasonably combined into a hybrid meta-heuristics to solve the cooperative 2E-LDPN optimization problem. This algorithm combines the merits of IPSO and ACO with local and global search capabilities, and redistributes customer zones on the basis of region partitioning solutions in order to rationalize transportation activities. Finally, an Improved Shapley value model is applied to guarantee profits allocation's fairness and is proved reliable in term of alliance stability. Empirical results out of a case study in Chongqing city show that the IPSO–ACO hybrid algorithm is superior to three well-known algorithms on the cost solution and the number of iterations. Using the Improved Shapley value model and strictly monotonic path (SMP) selection principles, optimal adhesion sequences for two alliances and a grand alliance are yielded. The implemented transition from two sub-alliances based network to the grand alliance is in line with real-world's practices and provides decision makers with a useful tool for the design of cooperative alliances. In addition, the proposed cooperation strategy and profit allocation method enable companies to increase cost savings and the logistics network's efficiency. Besides, semitrailer truck and vehicle sharing as feature of collaboration conditional clauses reduces the size of transportation fleets, and promotes greener logistics operations.

A paramedic's story of the Humboldt Broncos bus crash

On Friday 6th April, a semi-trailer truck collided with a coach bus carrying a junior hockey team and support staff, killing 16 and injuring 13, in Saskatchewan Canada. The accident devastated the country and drew international support. In this personal reflection, paramedic Jessica Brost shares her story of responding to the crash.

Investigation of road train divergent stability loss when moving along a program trajectory

The object of research is transport driven multilink wheel systems. In the development of the realized possibility of controlled movement of a semi-trailer truck along a program trajectory, the possibility of constructing a bifurcation set by a velocity parameter is considered. The velocity value is calculated for each discrete value of the calculated real trajectory. The trajectory can be specified in an explicit, implicit, parametric form or by the law of variation of the curvature radius. The study of this parameter is one of the most problematic places for analyzing the stability of the movement of a road train. Changes in this parameter at certain values, called bifurcation, lead to changes in the qualitative structure of the solutions of the system of differential equations and, as a result, divergent stability of the road train. For such an investigation of the phenomenon, the method of continuation by parameter and the first Lyapunov method are applied. During the research, many bifurcation velocity values are obtained. This is due to the fact that the proposed approach has a number of features, in particular, an iteration is performed for all control parameters of the program trajectory, and for each such value, the velocity has been iterated until its bifurcation value is reached. At each iteration, the roots of the characteristic equation are checked for the presence of at least one root with a positive real part, which corresponds to the bifurcation value of the parameter of the velocity of a road train according to Lyapunov. Due to this, it is possible to obtain this set by an exclusively analytical method using computer calculations, without resorting to the use of graphic-analytical methods. Obtaining these bifurcation sets can practically be used both to limit the velocity of a road train and to warn of its excess. Compared with similar known methods, this provides such advantages as a significant acceleration of the construction of this set and, as a result, its use in real time.

Anheuser-Busch orders 800 hydrogen-electric trucks from Nikola

US brewing giant Anheuser-Busch has placed an order for up to 800 hydrogen-electric powered semi-trailer trucks from Utah-based Nikola Motor Company. The zero-emission, articulated heavy trucks are expected to be integrated into Anheuser-Busch's dedicated fleet beginning in 2020.

Effects of Intentional Reduction in Moisture Content of Forest Wood Chips during Transport on Truckload Price

Wood chip transportation is a widespread practice in Poland, with distances between forest sites and power or heating plants reaching 300 km and truck transport times of up to 6 h. Because the basic parameter affecting biomass quality for energy production is moisture content, the objective of the presented economic analysis was to determine its effect on the price of wood chips transported by semi-trailer trucks. This paper considered the possibility of drying biomass in the semi-trailer. No external energy consumption was envisioned; the heat needed for drying was obtained from the truck cooling or exhaust systems via heat exchangers. The moisture content of transported biomass had a dual effect on the final truckload price. While it increased biomass amount by adding to its weight, it decreased its price by lowering its calorific value. Mathematical analysis showed that a decrease in wood chip moisture content increased truckload price, justifying research on technological improvements of this process. Simulations indicated that by reducing moisture content during transportation, biomass suppliers increased their revenues approximately € 3.6 to € 30.0 per truckload, which translates into annual financial profit ranging from tens of thousands of euros (EUR) to more than € 23,810.

French ROAD project developing refrigerated semi-trailers with fuel cell power supplies

The French ROAD (Refrigerated Optimized Advanced Design) project aims to develop a new generation of refrigerated semi-trailer (articulated) trucks, utilising more economical, less polluting and quieter technologies, including the integration of a fuel cell to provide power for ‘greener’ refrigerated semi-trailers during 2019.

Influence of semi-trailer truck operating conditions on road surface friendliness

In order to analyze the influence of semi-trailer truck operating conditions on road surface, a three-dimensional vehicle-pavement coupled model with 14 degrees of freedom is established for simulation and calculation. The influence of the different vehicle operating conditions on the dynamic tire loads, dynamic load coefficient (DLC) and road-friendliness which include road surfaces, vehicle speeds, vehicle loads are analyzed in this study. The results shown that the influence of the road surface roughness and vehicle loads on the tire dynamic load coefficient as well as road-friendliness is very obvious. Especially, the DLC values of the 3rd axle increase from 23.97 %, and 34.88 % when vehicle moves on three different road conditions with a velocity of 20 m/s and fully loaded. Finally, this study result gives the road-friendly limit of driving speed for 5-axle semi-trailer truck when vehicle operates under the different conditions.

Comparing the performance of suspension system of semi-trailer truck with two air suspension systems

In order to compare the performance of heavy truck suspension system, a 3D dynamic model with 14 degrees of freedom is developed with the dynamic models of the traditional and new air suspension systems to compare the performance of the air suspension systems for reducing the negative impacts on the road surface when vehicle moves on the different road conditions. Dynamic modes of two different types of the air suspension systems are respectively established and a dynamic load coefficient (DLC) is chosen as objective function which uses Matlab/Simulink software to simulate and determine the values of objective function. The results shown that the performance of the new air suspension system is better than the tradition air suspension for reducing the negative impact on road surface under the different operating conditions of vehicle. Especially, the DLC values of wheels at 3rd axle of vehicle with the new air suspension system are respectively reduced by 6.7 %, 7.0 %, 7.4 %, 7.7 % and 8.5 % in comparison with the traditional air suspension system when vehicle moves on the different pavement conditions a velocity of 20 m/s and fully loaded. In addition, the study results not only can provide a reference for designers but also traffic management to reduce the negative impact on road surface.

Iterative Refinement of Accelerations in Real-Time Vehicle Dynamics

A number of strategies can be followed for the real-time simulation of multibody systems. The main contributing factor to computational efficiency is usually the algorithm itself (the number of equations and their structure, the number of coordinates, the time integration scheme, etc.). Additional (but equally important) aspects have to do with implementation (linear solvers, sparse matrices, parallel computing, etc.). In this paper, an iterative refinement technique is introduced into a semirecursive multibody formulation. First, the formulation is summarized and its basic features are highlighted. Then, the basic goal is to iteratively solve the fundamental system of equations to obtain the accelerations. The iterative process is applied to compute corrections of the solution in an economic way, terminating as soon as a given precision is reached. We show that, upon implementation of this method, the computation time can be reduced at a very low implementation and accuracy costs. Two vehicles are simulated to prove the numerical benefits, namely a 16-degrees-of-freedom (DOF) sedan vehicle and a 40-degrees-of-freedom semitrailer truck. In short, a simple method to iteratively solve for the accelerations of vehicle systems in an efficient way is presented.