Wheeled Vehicles Research Articles

Analysis of the features of wheel out-of-roundness and construction of the wheel roughness spectrum of high-speed trains

ABSTRACT Wheel out-of-roundness (OOR), especially wheel polygonal wear, occurs frequently in high-speed wheels in China and has a significant influence on vehicle operation and wheel maintenance. The authors’ team has measured wheel OOR for more than 30,000 wheels with high-precision measuring instruments on nine types of high-speed EMUs over the past decade. In this study, the features of the wheel OOR are analyzed in detail and the wheel roughness spectrum is determined in both the narrow band and the 1/3 octave band. A method for inverting the wheel polygonal with the sine and catenary type is proposed. The analysis of the wheel OOR features, the establishment of the wheel roughness spectrum, and the resampling of wheel out-of-roundness profile from a roughness spectrum are of great importance for the simulation analysis of the dynamic wheel – rail interaction and rolling noise, as well as for the design of vehicle and track components.

Computational and experimental studies of vibration-protective properties of a pneumatic wheel of the MTZ-82 BELARUS tractor with external spring-hydraulic mini-suspension

BACKGROUND: Currently used in various sectors of the national economy, numerous wheeled suspensionless vehicles on pneumatic tires have a low level of vibration protection of the frame and limited cross-country ability. Therefore, the development and study of the design characteristics of a pneumatic wheel with increased elastic-damping properties and cross-country ability is a relevant technical problem. AIM: Development of the design and study the vibration-protective properties of a pneumatic wheel with an external spring-hydraulic mini-suspension to improve the ride smoothness and cross-country ability of large-sized suspensionless vehicles. METHODS: A description of the design of a wheel with mini-suspension and a support roller is presented. The wheel modeling was carried out in the PascalABC software, which takes into account the nonlinearity of the total force of the pneumatic tire and the spring-hydraulic mini-suspension, which is installed parallel to the tire at an angle to the vertical axis of the wheel. The test method consisted of comparison of free and forced vibrations of the rear pneumatic wheel of the MTZ-82 BELARUS tractor with a 400-965/15.5-38 tire, which operated without and with mini-suspension at a vertical load of 0.6 tons and various excessive pressure in the tire. RESULTS: The results of computational and experimental studies show that if the tire is radially compressed by 75 mm, the excess pressure inside the pneumatic wheel almost does not change, and if the pressure in the tire decreases from 1.6 to 0.4 bar, the resonant vibration frequency of the standard wheel axle decreases by 25%, while the dynamic coefficient remains unacceptably high (more than 5), leading to the tire breakaway from the supporting surface. Installing a mini-suspension parallel to the wheel in the form of a spring-hydraulic shock-absorbing strut leads to an increase in the resonant frequency by 1 Hz, however, the resonant peaks are reduced by almost 3 times to a dynamic coefficient of 2.5...2, which significantly increases the ride smoothness of suspensionless vehicles and reduces the likelihood of wheel breakaway from the supporting surface. CONCLUSION: It was found with the studies that the proposed wheel with a mini-suspension as a spring-hydraulic strut and a support roller has a relatively simple design, ensures high vibration-protective properties with small amplitudes of kinematic disturbance and can be used to improve the ride smoothness and cross-country ability of wheeled suspensionless vehicles.

Investigation of control system operation in plug-in four-wheel drive of wheeled vehicles on roller test benches

Investigation of control system operation in plug-in four-wheel drive of wheeled vehicles on roller test benches

СОГЛАСОВАНИЕ ГЕОМЕТРИЧЕСКИХ ХАРАКТЕРИСТИК ФАКТИЧЕСКОГО ПОВОРОТА КОЛЁСНОЙ МАШИНЫ

Based on the above calculation scheme of controlled curvilinear motion of a wheeled vehicle, it was revealed that the steering trapezoid causes some discrepancy between the kinematics of real and correct rotation. It is established that when adjusting the track width of the machine, the kinematic mismatch between the optimal rolling conditions of the wheels increases, and, consequently, the calculated dependences of the parameters of the ideal turn will not give a satisfactory result when analyzing the actual turn. The minimum theoretical turning radius is taken as an estimated indicator of the turnability of a wheeled vehicle. The conclusion of a multifunctional analytical dependence for determining the theoretical minimum turning radius of a wheeled vehicle, the wheels of which are controlled by a steering trapezoid, is presented. The resulting formula includes the longitudinal base of the machine, the pin track, the angles of rotation of the inner and outer steerable wheels. A comparison of the calculation results according to the developed and known formulas is given, which confirmed the complete convergence. It was found that, for example, an increase in the pivot track of the machine by 0.2 m leads to an increase in the theoretical minimum radius of the actual turn by 16.5%, and the distance from the continuation of the rear axle to the instantaneous center of rotation by 45.07...98.02% when the angle of rotation of the inner steering wheel changes from 20° to 40°.

МАТЕМАТИЧЕСКОЕ МОДЕЛИРОВАНИЕ БОКОВОГО СКОЛЬЖЕНИЯ КОЛЕСНОЙ МАШИНЫ ПРИ ПОВОРОТЕ

The condition for the occurrence of lateral sliding of a wheeled vehicle when turning is determined. Analytical dependences are presented to determine the radius of rotation of the center of gravity of the machine as a function of time, heading angle, acceleration and speed of lateral sliding, and lateral withdrawal of the machine. A mathematical model of the lateral sliding of a wheeled vehicle when turning in the SimInTech program has been developed. A simulation of the lateral sliding of a wheeled vehicle when turning 180 degrees was performed, using the example of the Belarus-80.1 tractor. It shows that the withdrawal of the car in the lateral direction begins at the end of the section of the entrance to the turn, when the radius of rotation of the center of gravity of the car has significantly decreased, but due to the still small values of acceleration and the speed of lateral sliding, the withdrawal in this section is not significant (for the example considered less than 1 cm). In the repartitions of the section of steady rotation (with a constant radius of rotation of the center of gravity of the machine), the acceleration of lateral sliding is constant, but the speed of lateral sliding increases and, accordingly, the withdrawal of the machine in the lateral direction increases (for the example under consideration up to 43 cm). At the beginning of the exit section of the turn, with an insignificant increase in the radius of rotation of the center of gravity of the machine, the acceleration of the side slide decreases, but the speed of the side slide continues to increase until the acceleration of the side slide becomes equal to 0. As the machine moves in the exit section of the turn, the radius of rotation of the center of gravity of the machine increases, the acceleration of the side slide will be negative and directed in the opposite direction from the direction of the side slide speed, the latter decreases, but the withdrawal of the machine in the side direction continues, reaching a maximum value (for the example considered 1.12 m) at a side slide speed equal to 0.

The Study Peculiarities of Market Valuation of Wheeled Vehicles in Operation

The article critically examines the common practice of wheeled vehicles valuation and substantiates complex forensic approaches and methods for determining their market value. Specific aspects of using a comparative approach to the valuation of wheeled vehicles are discussed, and the procedure for the calculation is substantiated.Basic framework of vehicles average price calculation reviewed in the article can be used in the set of forensic vehicle commodity examination methods, which are now under development.

Validation of a new road and contact model for vehicle–soft soil terrain interaction through an elaborate modelling of the FED-Alpha vehicle

Employing multibody dynamic simulations with semi-empirical tyre models is widely recognised as a cost-effective approach. A recent development introduces a novel road and tyre–soil contact model that is not only swift and memory-efficient but also addresses limitations in classical semi-empirical models. This study conducts a thorough validation of the new road and contact model by creating a detailed multibody model of the four-wheeled vehicle, Fuel Efficiency Demonstrator – Alpha, integral to NATO’s Next-Generation reference mobility model. The comprehensive model encompasses the chassis, suspension, tyres, engine, transmission and various other components. Through simulations of various driving scenarios, accounting for complex terrain geometries, spatially varying soil properties and multi-pass phenomena, the model’s performance is evaluated. The simulation results are compared with physical measurements, providing a detailed assessment of the tyre–soil model’s predictive accuracy for wheeled vehicle mobility on deformable terrains.

Wheel wear of mountain metro vehicles with complex line conditions

Purpose Mountain metro vehicles have unique wheel wear characteristics due to the complex flat and longitudinal lines. With a combination of flat and longitudinal curved tracks, the traction and braking conditions are more frequent in mountain metro vehicles. This paper aims to analyze the wheel wear characteristics of mountain metro vehicles in complex flat and longitudinal lines. Design/methodology/approach A dynamic model of the mountain metro vehicle and a wear model are established to analyze the dynamic and wheel wear characteristics of mountain metro vehicles. The wheel wear law of mountain metro vehicles under complex track conditions is analyzed, and the suppression measure based on variable stiffness rotary arm nodes of mountain metro vehicles is proposed. Findings The results showed that the maximum wheel wear depth without considering the ramp track and considering the ramp track are 3.283 mm and 3.717 mm, respectively; the maximum wheel wear depth increases by 13.2%. Wheel wear can be effectively suppressed by the variable stiffness rotary arm model, and the maximum wear depth of the wheel profile is 3.316 mm, which is reduced by 10.79% compared with the constant stiffness model. Originality/value A dynamic model of a mountain metro vehicle is established, and the metro vehicle wheel wear under the large ramps under the traction and braking conditions is analyzed, and the metro vehicle wheel wear suppression measure based on variable stiffness rotary arm nodes is proposed. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2024-0247

Simulation analysis of force and fatigue life of circular wheel of crawler vehicle

During loading and driving, the wheels bear the vertical load from the body mass and the excitation load generated by uneven road surface on the one hand, and bear the driving torque on the other hand. The load-bearing methods of wheels are generally divided into bottom load-bearing and top load-bearing. This paper describes the structural characteristics of the track system of the articulated track vehicle and the interaction relationship between the main components of the track system. Finite element calculation is carried out based on ANSYS software to obtain the stress distribution of each key component under various loading methods. It can be seen from the results that all key components of the track system can meet the strength and rigidity requirements; although there are also areas with large local stress, they are all within the safe range, which is mainly caused by stress concentration. Safe life is obtained through fatigue analysis.

Automatic determination of directional stability parameters of an electric vehicle with a two-motor scheme as part of the torque distribution controller

In case if the front and rear axle of the electric vehicle are not mechanically linked, the presence of automatic torque distribution to the axles or wheels becomes not only an addition to increase the level of consumer properties, but also a necessity. A method for determining the directional stability condition of an electric four-wheel drive vehicle is developed as part of the research by comparing the target and measured yaw rate, and is based on the formulated conditions of drift, skid, and counter steer registration. A method for detecting slipping of the driving wheels of an electric vehicle with a dual-motor scheme is developed, which is based on comparing the target and measured velocity differences of the front and rear axle and includes an auto oscillation detection function. A method for determining the target front and rear axle speed difference in a corner is described. Based on the tests performed, it is concluded that the proposed methods are applicable to the active torque distribution function between the axles of an all-wheel drive electric vehicle being developed by the authors of the paper, which provides improved directional stability and controllability, and counteracts slipping of the drive wheels.

Prehospital factors associated with mortality among road traffic injury patients: analysis of Cameroon trauma registry data

BackgroundCameroon is amongst the worst affected countries by road traffic injuries with an estimated 1443 disability-adjusted life years per 100,000 population. There have been very limited reports on the crucial prehospital response to road traffic injuries in Cameroon. This study aimed to identify prehospital factors associated with RTI mortality in Cameroon.MethodsWe included patients enrolled between June 2022 and March 2023 in the Cameroon Trauma Registry. Information about prehospital factors and demographic data was obtained from patients or their proxies. We examined the association of prehospital care factors like care at the crash scene and type of transportation during crash with final patient outcome. We used Chi-squared test to investigate the association between selected independent variables and mortality. A multivariable logistic regression model was built to identify independent predictors of dying from an RTI.ResultsRTIs constituted 69.5% (n = 3203) of all injuries in the Cameroon Trauma Registry. Only 20.7% (n = 102) of 4 + wheel vehicle occupants had seatbelts on and just 2.7% (n = 53) of motorcycle riders were wearing helmets during the collision. Only 4.9% (n = 156) of patients received any form of scene care. In-hospital mortality was 4.3% (n = 139) and was associated with male sex (AOR = 1.7, 95%CI = 1.08–2.80), crashing on a motorcycle (AOR = 2.08, 95%CI = 1.1–3.67) and scene care (AOR = 0.25, 95%CI = 0.04–0.80).ConclusionsReceiving any type of care at the scene such as bleeding control or being placed in the recovery position by bystanders is associated with improved survival. Improving on existing informal prehospital care responses should be a priority in Cameroon.

Pengaruh Penambahan Zat Aditif Anti Striping (WETFIX-BE) Pada Kinerja Campuran Aspal Beton (AC-WC)

The asphalt concrete layer is the top layer of road pavement construction which is in direct contact with vehicle wheel loads and the influence of weather. One type of asphalt concrete layer is Asphalt Concrete – Wearing Course (AC–WC). Asphalt functions as an aggregate adhesive. In asphalt concrete mixtures it is very important to maintain its characteristics. During the maintenance period, the mixture will easily experience striping or peeling of the asphalt from the aggregate. To maintain and improve the properties of asphalt, one way is to use an anti-striping additive, this additive is Wetfix-Be, which is a compound that contains chemicals. Anti-peeling materials are only used if the residual Marshall stability value (IRS-Index of Retained Stability) or the Indirect Tensile Strength Ratio (ITSR) value of the asphalt mixture before adding the anti-peeling agent is less than required. If an anti-flaking agent must be used then before the anti-flaking agent is added to the mixture, the residual marshall stability (after 24 hour immersion, 60 °C) must be at least 75%.

Mathematical Modeling Features of the Wheeled Vehicle Movement with an Automated Braking Control System

Mathematical Modeling Features of the Wheeled Vehicle Movement with an Automated Braking Control System

Проєктування цементобетонного покриття на залізобетонній плиті мостового полотна автодорожніх мостів

ntroduction. Road bridges are an important part of the road network of the transport infrastructure of Ukraine. Nowadays a large number of road bridges do not meet the modern requirements for ensuring road traffic safety and structural reliability of building elements. Problems. It was established that there is a need to develop a method of designing a cement-concrete coating on a reinforced concrete slab of the carriageway of road bridges Goal. To propose an approach for designing a cement-concrete coating on a reinforced concrete slab of the carriageway of road bridges. Results. The strength calculation was performed when assessing the limit state of the cement-concrete coating in terms of crack resistance from the joint action of vehicles and temperature changes. The measures of damage to the cement-concrete coating on the reinforced concrete slab of the carriageway of road bridges due to tensile stresses arising from the action of pneumatic wheels of vehicles were determined. Conclusions. The paper proposes approaches to the design of a cement-concrete coating on a reinforced concrete slab of the carriageway of road bridges

Design of multimodal transformable wheels for amphibious robotic vehicles

Amphibious vehicles are versatile for locomotion on both water and land; to reduce the complexities of structure and control, an amphibious vehicle is expected to use a single propulsion system without additional screw propellers or water jets; as vehicles are typically driven by wheels that are efficient for smooth land locomotion, how to make the wheels also as water propellors for multimodal transformations is meaningful, while such wheels are less explored. From this motivation, in this short article, we report the design of a multimodal transformable wheel with three driving modes (wheel mode, forward-propellor mode, and backward-propellor mode) and the integrated mode-locks for each driving mode. To achieve the multimodal transformations of the wheel, we design the integrated mode-transform mechanism and mode-lock mechanism, the two mechanical implementations are driven by only two actuators and are compact with low inertia and low control complexity, with the kinematic properties provided during the wheel transformations.

Design of motion control system for unmanned wheeled electric vehicle

Abstract The unmanned wheeled electric vehicle is a weapon platform that draws significant attention in current and future battlefields, and research on its motion control is fundamental. This paper introduces the design of a 6×6 unmanned wheeled electric vehicle and discusses the motion control methods applicable to this vehicle. The electric drive system of this vehicle comprises six independent asynchronous motors and corresponding motor controllers. A comprehensive controller designed based on DSP connects the six motor controllers. As it is an experimental platform, the motion control algorithms are deployed on an onboard computer, which connects to the comprehensive controller. Using the Backstepping method, the kinematic control algorithm for the 6×6 unmanned wheeled electric vehicle is designed. The global asymptotic stability of the control system is proven through the Lyapunov function, and its control performance is verified via simulation experiments. Finally, the system is deployed and tested on the actual vehicle. Experimental results show that the motion control system designed in this paper enables the unmanned wheeled electric vehicle to achieve effective motion control. The control laws derived from the Backstepping method are relatively simple and have low requirements for the sampling period. In practical systems, output speed magnitude and rate of change must be limited to stay within allowable system parameters.

Effect of Design Parameters on Buckling Tendency of an Eccentric Drag Link Used in a Truck Steering Linkage: A DoE/RSM-Based Design Optimisation Study

The steering system, deemed one of the most critical subsystems for ensuring the safety of a vehicle, is characterised by its pivotal role in manoeuvrability and control. The primary function of transmitting the steering input from the steering wheel to the vehicle's wheels is carried out by the drag link within the steering system. Therefore, the durability and proper functioning of the drag link in vehicles, especially carrying heavy loads, are of critical importance for both safety and efficiency. The main purpose of this study is to determine the optimal geometry of the drag link utilised in the steering system of a 4x2 truck using the Design of Experiments-Response Surface Methodology (DoE-RSM). Firstly, an idealised worst-case load model was used to determine the maximum force applied by the Pitman arm on the drag link. The stress distribution and deformation on the drag link caused by the maximum design load were deter-mined using Finite Element Analysis (FEA). Based on the results of the analyses, eccentricity, rod thickness, and fillet radius were defined as design parameters. The parameter ranges were determined by considering the volume swept by the wheel and buckling criteria under maximum load conditions. According to the DoE-RSM results, concerning the local sensitivity per-centages of the parameters on total deformation, it was observed that the eccentricity (e) parameter has the most significant impact, with an approximate positive rate of 74%.

Front Wheel Shimmy Control Method of Electric Wheel Vehicles Based on Homogeneous Domination

Front Wheel Shimmy Control Method of Electric Wheel Vehicles Based on Homogeneous Domination

Evaluation of Flexible Pavement Friction Coefficients: A Case Study of East-West Highway Near Mahendranagar City, Nepal

Friction is a crucial factor in highway engineering, as it affects the traction between a vehicle's wheels and the road surface. This traction significantly influences the movement, speed, and efficiency of vehicles on highways. The coefficient of friction depends on various factors, such as pavement materials, traffic volume, road age, temperature, and weather conditions. The Skid Resistance Test Method is adopted for the study, which involves using a Portable Skid Resistance Tester to measure the British Pendulum Number (BPN) and then calculating the coefficient of friction by dividing the BPN by 10. An evaluation of a 5 km stretch of the East-West highway near Mahendranagar Bazaar revealed a longitudinal coefficient of friction of 0.354 and a lateral coefficient of friction of 0.184 under both dry and wet conditions. These findings were relevant for design speeds ranging from 60 to 80 km/h and considered an Annual Average Daily Traffic (AADT) of 10,321 Passenger Car Units (PCU) during the year 2023/2024. The assessment also indicated a variance of 0.19% and a poor International Roughness Index (IRI) value of 2.05. These aggregates had specific gravities ranging from 2.6 to 2.67 and were sized at 13.2 mm. The application rate for the aggregates ranged from 12 to 15 kg per square meter. It is important to note that a higher coefficient of friction leads to reduced vehicle efficiency. Thus, it is crucial to carefully consider the coefficient of friction values and detailed specifications to ensure traffic safety and road integrity.

Dynamic Measurement Method for Steering Wheel Angle of Autonomous Agricultural Vehicles

Steering wheel angle is an important and essential parameter of the navigation control of autonomous wheeled vehicles. At present, the combination of rotary angle sensors and four-link mechanisms is the main sensing approach for steering wheel angle with high measurement accuracy, which is widely adopted in autonomous agriculture vehicles. However, in a complex and challenging farmland environment, there are a series of prominent problems such as complicated installation and debugging, spattered mud blocking the parallel four-bar mechanism, breakage of the sensor wire during operation, and separate calibrations for different vehicles. To avoid the above problems, a novel dynamic measurement method for steering wheel angle is presented based on vehicle attitude information and a non-contact attitude sensor. First, the working principle of the proposed measurement method and the effect of zero position error on measurement accuracy and path tracking are analyzed. Then, an optimization algorithm for zero position error of steering wheel angle is proposed. The experimental platform is assembled based on a 2ZG-6DM rice transplanter by software design and hardware modification. Finally, comparative tests are conducted to demonstrate the effectiveness and priority of the proposed dynamic sensing method. Experimental results show that the average absolute error of the straight path is 0.057° and the corresponding standard deviation of the error is 0.483°. The average absolute error of the turning path is 0.686° and the standard deviation of the error is 0.931°. This implies the proposed dynamic sensing method can accurately realize the collection of the steering wheel angle. Compared to the traditional measurement method, the proposed dynamic sensing method greatly improves the measurement reliability of the steering wheel angle and avoids complicated installation and debugging of different vehicles. The separate calibrations for different vehicles are not needed since the proposed measurement method is not dependent on the kinematic models of the vehicles. Given that the attitude sensor can be installed at a higher position on the wheel, sensor damage from mud blocking and the sensor wire breaking is also avoided.