Wheel Center Research Articles

Совершенствование технологий ремонта и изготовления соединений с натягом элементов колесных пар железнодорожного подвижного состава

In this article the main directions for increasing the operational reliability of tension joints for wheel pair elements of railway rolling stock have been given. Particular attention has been paid to such joints as “axis – wheel hub”, “axis – inner rings of axis bearings”, “wheel center – tire”. A number of technical and technological solutions have been proposed aimed at improving the technology for repair work and control of tension joints. These solutions ensure the cost reduction of repair work, as well as the increase in the safety of train traffic.

Investigation of Epicycloid Mechanism Dynamics

A dynamic analysis of a planetary mechanism with a satellite in external engagement is presented, where the central wheel is fixed. The trajectory of a driven link of such type of mechanism allows it to use it in machines, which provides technological processes where the executive or output link carries out pulsating motion which is required during of stop of the driven link. Mechanisms of this type mainly are used in the textile industry, where the processing of a material requires the actuator to be able to make minor fluctuations with respect to the temporal position. Here mentioned, determines the necessity of solution not only problems of kinematics but also here given system’s dynamic analysis, which would be used during design of such epicycloid mechanisms. Based on the mentioned, below is given the methodology of calculation of dynamic parameters of epicycloid mechanism

Investigation of Pericyclic Mechanism’s Kinematics

A kinematic analysis of the pericyclic mechanism, where the gear is internally engaged with fixed central wheel is presented. Geometric features the trajectory of the mechanism allows use of this type of mechanisms in machines, which provides such kind of technological processes where slight fluctuations of the driven link sometimes are necessary at the extreme position of the system. Mechanisms of this type are used in the light industry, where the processing of any tissue requires slight fluctuations of the executive body at the temporary position.

A Real-Time Sinkage Detection Method for the Planetary Robotic Wheel-on-Limb System via a Monocular Camera

When traversing soft and rugged terrain, a planetary rover is susceptible to slipping and sinking, which impedes its movement. The real-time detection of wheel sinkage in the planetary wheel-on-limb system is crucial for enhancing motion safety and passability on such terrain. Initially, this study establishes a measurement of wheel sinkage under complex terrain conditions. Subsequently, a monocular vision-based wheel sinkage detection method is presented by combining the wheel–terrain boundary with the wheel center position (WTB-WCP). The method enables the efficient and accurate detection of wheel sinkage through two-stage parallel computation of the wheel–terrain boundary fitting and wheel center localization. Finally, this study establishes an experimental platform based on a monocular camera and the planetary rover wheel-on-limb system to experimentally validate and comparatively analyze the proposed method. The experimental results demonstrate that the method effectively provides information on the wheel sinkage of the planetary rover wheel-on-limb system, and the relative errors of the method do not exceed 4%. The method has high accuracy and reliability and is greatly significant for the safety and passability of planetary rovers in soft and rugged terrain.

3D rolling contact finite element analysis of high-speed railway turnout considering ratchetting effect

The present work introduces a three-dimensional finite element model for the wheel-turnout-sleeper system, incorporating a cyclic constitutive model that accurately captures the nonlinear hardening behavior of rail steel under cyclic loadings. At the same time, a mixed implicit-explicit finite element method is employed to investigate the transient rolling contact behavior of wheel-turnout. Through dynamic analysis, the transient rolling contact status of the wheel-turnout, stress and strain responses of the turnout, and wheel-rail forces are investigated under varying crossing speeds and number of cycles. It is found that during the wheelset crossing, the contact stress remains relatively stable on the stock rail, and multi-point contact occurs at the wing rail and long point rail, and the contact stress on the surface of the long point rail is more significant. With an increase in crossing speed in the same cycle, there is a gradual rise in contact stress on the long point rail face. At the same crossing speed, with the increase in the number of cycles, the contact position between the wheelset and the long point rail gradually moves back, and the top width of the contact position gradually expands. Meanwhile, the fluctuation range of vertical displacement of the wheel center diminishes, and the wheel flange moves away from the long point rail. Additionally, a progressive accumulation of ratcheting strain is observed on the rail, and the ratcheting strain on the long point rail significantly exceeds that on the stock rail. The research results will help to provide a reference for the optimization and design of the critical cross-section profile of the long point rail and will have guiding significance for the maintenance and repair of turnouts.

Design And Development Of A Spiral Tube Water Wheel Pumping System: A

This paper provides an overview of the ancient evolution,design and development of different types of spiral tube water wheel pumping system (STWWPS). It has always been a challenge to lift water and carry it to some other locations for executing meaningful work, making use of the alternative sources of power. Several kinds of non-conventional energy sources and techniques have been tried. Each one is having its own merits and demerits. Making use of the kinetic energy of flowing water can be achieved through different kinds of water wheel.Spiral tube powered by kinetic energy of flowing water has been utilized for lifting and carrying water for irrigation and other purposes, contributing to the replacement of conventional diesel and electric power sources. These conventional sources are expensive (Diesel) and often unreliable in rural areas (Electricity).This review paper examines the design, development, and performance evaluation of various spiral tube pumping systems, including single, double, multilayer, pedal type, four scoop type, and multi-purpose models. It examines the load torque, power, efficiency, and stress analysis of shaft and bearing, and the impact of rotational speed, submerged ratio, and number of spiral pipes on the performance of the pumping system.The working principle allows these pumps to create a column of water within its coil that alternatively the air which is compressed as it moves towards the center of wheel. These pumpsnot only save electricity and diesel cost but the maintenance cost is also lowapart from contributing to the clean environment.

Vibration-reducing modelling of a mecanum wheel based on equivalent stiffness and strength analysis

The mecanum wheel-chair offers unparalleled manoeuverability due to its ability to move in any direction by independently rotating its wheels. However, this innovation, characterized by hub and rollers, brings along a set of challenges, including vertical vibrations induced by successive roller-ground contacts. This manuscript presents a comprehensive investigation into the dynamic features and vertical vibration characteristics of mecanum wheels. Our study focuses on understanding the impact of roller curvature on vertical vibrations. To achieve this, authors employed top-to-top and quadratic mean values of accelerations and displacements. Additionally, authors described the results of a vertical vibration simulation conducted in SolidWorks. A key element of our research involves the implementation of a spring mechanism within the mecanum wheel's centre to dampen vibrations. Through systematic experimentation and analysis, authors determined the optimal geometric arrangement for minimizing vertical vibrations. Our findings reveal a superior design approach for reducing wheel vibrations and enhancing manoeuverability. By addressing this important issue, authors contribute to the advancement of mecanum wheel technology, making it more efficient and practical for a wide range of applications. Specifically, our results demonstrate an impressive 99.98% reduction in vertical vibrations, marking a significant improvement in the mecanum wheel-chair's efficiency and enhancement in wheel efficiency.

A differential-algebraic extended Kalman filter with exact constraint satisfaction

This work proposes an Augmented Manifold Differential-Algebraic Extended Kalman Filter for state and input estimation for multibody systems described by a set of differential algebraic equations. The proposed Kalman Filter allows for exact constraint satisfaction and does not require reformulation of the multibody system equations. The approach consists of two main steps: (i) elimination of the Lagrange multipliers from the system state via a nullspace projection and (ii) an additional correction step that constrains the a-posteriori estimated system state to lie on the constraint manifold. The latter is achieved by solving a constrained optimization problem using a Euclidean descent approach and projection on the constraint manifold, i.e. manifold optimization. The proposed approach is numerically validated on both open and closed kinematic chain rigid multibody models and is shown to be robust and indifferent to the type of kinematic chain being considered. Furthermore, an experimental validation is carried out where the forces and torques acting on the wheel center of a McPherson car suspension test setup are successfully estimated using a flexible multibody model and the proposed Kalman Filter.

DYNAMIC LOADING EFFECTS ON CAR SUSPENSION COMPONENTS DURING ROAD DRIVING

Suspension system plays a vital role in providing a pleasure and safe driving experience. Because of that, studying the behaviour of suspension system during road driving is crucial. This paper describes the work carried out to investigate the dynamic loading effects on suspension components during rough road driving and analyse based on safety factor and fatigue life. A multibody simulation using SolidWorks software is conducted. Von Mises stress, strain, and displacement distribution plots are generated to visualize stress and deformation patterns. Fatigue life distribution plots indicate infinite fatigue life strength for the majority of components. Kinematic and compliance test examines roll centre, vertical movement of the wheel centre, toe angle and camber angle. This comprehensive analysis contributes to suspension system design and optimization, improving vehicle safety and durability.

Spatial contextual cues that help predict how a target will accelerate can be used to guide interception.

Objects in one's environment do not always move at a constant velocity but often accelerate or decelerate. People are very poor at visually judging acceleration and normally make systematic errors when trying to intercept accelerating objects. If the acceleration is perpendicular to the direction of motion, it gives rise to a curved path. Can spatial contextual cues help one predict such accelerations and thereby help interception? To answer this question, we asked participants to hit a target that moved as if it were attached to a rolling disk, like a valve (target) on a bicycle wheel (disk) moves when cycling: constantly accelerating toward the wheel's center. On half the trials, the disk was visible such that participants could use the spatial relations between the target and the rolling disk to guide their interception. On the other half, the disk was not visible, so participants had no help in predicting the target's complicated pattern of accelerations and decelerations. Importantly, the target's path was the same in both cases. Participants hit more targets when the disk was visible than when it was invisible, even when using a strategy that can compensate for neglecting acceleration. We conclude that spatial contextual cues that help predict the target's accelerations can help intercept it.

The role of 3D contact geometry in modeling dynamic wheel-rail interaction at short-wave irregularities on rail surface

Modelling wheel-rail interaction at short-wave irregularities is an important issue under the context of vehicle-track system dynamics for analyzing and preventing severe impact. The present paper broadens the applicability of vehicle-track dynamics model to account for 3D short-wave irregularities on rail surface. The key is developing a meshing grid approach combined with the accurate conjugate gradient (CG) method for contact mechanics under arbitrary 3D contact geometry. Therefore, both the global dynamics and local contact solutions can be provided. In this study, short-pitch rail corrugation is employed for investigating the role of 3D contact geometry in modelling dynamic wheel-rail interaction. The traditional vehicle-track coupled dynamics model using Hertzian spring is used for comparison. The results show short-pitch rail corrugation contributes two different aspects, i.e., wheel center trajectory and time-varying contact stiffness. These two aspects are found to be the root causes for explaining the influence of the varying 3D geometry irregularity size on dynamic wheel-rail contact force.

Oscillatory processes in a nonlinear system of an individual traction electric drive

When the tires interact with the road in contact, self-oscillations occur. The appearance of self-oscillations in the interaction zone can serve as a useful diagnostic sign of the development of the process of loss of adhesion in the work, cases of self-oscillations for an individual electric drive are investigated. In traction and driven modes, a "soft" mode of occurrence of self-oscillation of wheel rotation is possible. When braking, there is a "soft" mode of excitation of self-oscillations, and when the wheels are locked, a "hard" mode of self-oscillations of the translational movement of the wheel center. Keywords: self-oscillation; frictional interaction of the wheel with the base; "soft mode" of self-oscillation; "hard mode" of self-oscillation; Bendixon criterion; friction force; individual electric wheel drive

ГЕОМЕТРИЧЕСКИЙ АНАЛИЗ И ТЕОРЕТИЧЕСКАЯ ОЦЕНКА КПД ПЛОСКО-КОНИЧЕСКОГО ЗАЦЕПЛЕНИЯ СФЕРИЧЕСКОЙ РОЛИКОВОЙ ПЕРЕДАЧИ

The study objective was to assess the influence of friction factors and geometric parameters of a spherical rolling screw motion drive on its efficiency. The load is transferred by means of a cone-and-plate engagement of two rows of rollers mounted on a satellite with fixed and driven plate central gears. With the help of a spherical rolling screw motion drive, it is possible to realize a wide range of gear ratios (16...200) and reduce the material capacity of the gearbox, ensuring the ratio of its mass to the nominal transmitted torque of less than 0.1 kg/(N•m). The main task of this research is to find out the ascent angle of the spatial closed center curves with the help of which the surfaces of the central wheel teeth are formed. The research methods are based on the application of the classical mechanics laws and computer modeling algorithms in NX system. The novelty of the research is in the novelty of the technical object under study, its low level of being studied, the lack of detailed methods of its calculation and design. As a result, based on the analysis of the geometric satellite model, the equations of the center curves are obtained and an algorithm for determining the ascent angle of the center curve in the middle section of the central wheel teeth is developed, which allows power analysis of the motion drive. The applicability of the formula for calculating the average ascent angle of a piecewise helical curve located on a cylindrical surface for spherical motion drives is evaluated and the necessity of its adjustment taking into account a given gear ratio and the inclination angle of the drive shaft crank is found out. An algorithm is developed for the theoretical study of the efficiency of spherical roller gears at the design stage.

Displacement reconstruction based on Kalman smoothing in multi-rate suspension health monitoring systems

Suspension displacements and wheel center accelerations are important signals for suspension health monitoring systems to improve vehicle reliability and safety. The current way to obtain these signals is to install sensors on vehicles to conduct direct measurements. Usually, displacements are sampled at a slower rate than accelerations due to technical or economic limitations in real scenarios. This paper introduces a method for displacement reconstruction with low-sampling-rate displacement and high-sampling-rate acceleration measurements by formulating the reconstruction problem as a state estimation problem. A state-space model is established by identifying two data-driven models: a time-series Auto-Regressive model and a Finite Impulse Response model. Then, Kalman smoothing is used to estimate the displacement. A series of experiments have been done to show that the estimates from Kalman smoother coincide with the measurements.

Method for detecting the loss of stability of the movement of tractors when towing a trailer or a coupled unit

BACKGROUND:Currently, combines and tractors, being the most energy-intensive transport and technological machines for agricultural purposes, largely determine the possibility of transition to an efficient and environmentally friendly agricultural economy, and also provide the technical aspect of the transformation of the agro-industrial complex into the leading sector of the countrys industry. One of the sources of dynamic loads in the units and subsystems of tractor equipment are self-oscillating modes.
 AIMS:Study of the conditions for the occurrence of self-oscillating processes in the design of wheeled tractor trains and development of methods to increase the handling and safety of their movement by means of reducing the galloping and yawing of the tractor-tractor when towing heavy loads.
 METHODS:It has been established that due to the coupling of oscillations along the longitudinal displacement of a truck tractor and a trailer with oscillations along the vertical displacement of the center of mass and with pitch angle oscillations of the truck tractor, when an auto-oscillatory mode occurs in the interaction zone of an elastic wheel with a solid surface, the same mode of self-oscillation will occur along the mentioned degrees of freedom. Moreover, it is possible to specify the sequence of occurrence of self-oscillating modes in different zones of the tractor train design.
 RESULTS:First, self-oscillations are excited in the contact patch of a wheel with a solid surface when a complete slip occurs, then self-oscillations along the pitch angle of a truck tractor body begin and after that self-oscillations along the vertical displacement of the center of mass of a truck tractor occur. Folding angle oscillations of a tractor train are associated with oscillations of the translational motion of wheel centers, which lead to the emergence of an self-oscillating mode, both with partial and full slip in the interaction zone of an elastic tire with a solid surface. Since the self-oscillations of each of the wheels occur at random times, the self-oscillations of a truck tractor along the folding angle will be chaotic.
 CONCLUSIONS:The practical value of the study lies in the possibility of using the proposed methods to identify the danger of self-oscillating processes in the design of promising types of agricultural machinery.

Research on Receiving Seeds Performance of Belt-Type High-Speed Corn Seed Guiding Device Based on Discrete Element Method

Because the initial speed of the seeds leaving the seed disk is too high, they collide and bounce off the inner wall of the seed guide tube, resulting in poor sowing quality when corn is sown at high speeds above 12 km/h. This study clarifies the primary factors affecting the stability of seed receiving and the accuracy of the seed entering the seed cavity, establishes the dynamic model of seed clamping, transportation, and releasing, and investigates the belt-type high-speed corn seed guiding device with the seed receiving system as the research object. It also proposes an improved method of adding herringbone lines on the finger surface to address this issue. Using EDEM software, a virtual experiment of seed-receiving performance was conducted, and the change trend of stress on seeds with and without a herringbone pattern and different wheel center distance as well as the change trend of the speed of seeds with various feeder wheel speeds and finger length, were both examined. The outcomes of the simulation demonstrate that the herringbone-lined feeder wheel could increase the stress on seeds. The average value of the stress on the seeds is the highest at the wheels’ center distance of 37 mm. The stability and speed fluctuation of seeds introduced into the seed cavity were better when the feeder wheel speed was 560 r/min. The speed of fluctuation and stability of the seeds introduced into the seed cavity were better when the finger length was 12 mm. The high-speed camera test on the test bench was used to verify the seed guiding process in accordance with the simulation results, and the outcomes were largely consistent. The study’s findings can serve as a theoretical foundation for a belt-type high-speed corn seed guiding device optimization test.

Rolling friction torque generated by time delay during stress wave transmission

A new type of rolling resistance was discovered in Shinkansen trains. Rolling resistance at 300 km/h is four times larger than at low speeds. This increased part of the rolling resistance is proportional to the train’s speed. The reason is currently unknown. This paper makes it clear. The stress in the contact area travels upwards and reaches the axle with some delay. The delay time affects the stress distribution at a high speed running. The 3D-distributed stress approximately satisfies recurrence equations that can be solved numerically. The result reveals that the stress distribution is shifted forward from just below the wheel center. The frictional resistance calculated by this theory agrees well with the experimental values measured on Shinkansen 700 series.

Edge-computing based soft sensors with local Finite Impulse Response models for vehicle wheel center loads estimation under multiple working conditions

Wheel center loads are usually required to be measured for the durability assessment of vehicle key components, and thus play an important role in the reliability design of vehicles. The current method of obtaining these loads is to install sophisticated and expensive sensors on prototype vehicles to conduct direct measurement. However, it is economically infeasible to equip many prototype vehicles simultaneously for road testing. The paper aims to design and implement edge-computing based soft sensors to estimate these wheel center loads in real time. A set of Finite Impulse Response (FIR) models are trained offline under multiple working conditions, and a Maximum Likelihood Estimation (MLE) classifier is used to determine which working condition the vehicle currently is under so that the wheel center loads can be estimated accurately. The soft sensors are implemented with an edge computing paradigm, and the whole process of data collection, pre-processing, calculation, and upload runs automatically on edge devices. Experimental results show that the estimate from the proposed method fits the measurement well, and the edge-computing based soft sensors meet the real-time requirements for wheel center load estimation.

Multibody dynamics modelling of a 6-axle truck to quantify the effects of pavement and vehicle parameters on dynamic loads

ABSTRACT The actual service life of the pavement is related to dynamic tire loads. To accurately calculate dynamic loads, a multibody dynamics model of a 6-axle heavy truck was developed. The difference between simulated and experimental RMS values of wheel centre force and acceleration was within 15%. Based on the validated dynamics model, the effects of ride quality index (RQI), vehicle speed, load capacity, and suspension damping coefficient on dynamic impact factor (DI) and dynamic load amplitude (DLA) were explored. When the vehicle was fully loaded, both DI and DLA increased with decreasing RQI, increasing vehicle speed, and increasing suspension damping coefficient. Among them, the effect of RQI and vehicle speed on DLA and DI was much greater than that of suspension damping factor. In addition, the dispersion of DI values for each axle increased as the vehicle mass decreased. Therefore, it is necessary to consider the combined effects of RQI, vehicle speed and load capacity when applying dynamic tire loads in pavement design or life estimation. The procedure in this paper facilitates the accurate calculation of dynamic loads for different pavement and vehicle parameters and is recommended to be used in vehicle-pavement coupled analysis.

Chemical bonding and dynamic structural fluxionality of a boron-based Al2B8 binary cluster: the robustness of a doubly 6π/6σ aromatic [B8]2- molecular wheel.

Despite the isovalency between Al and B elements, Al-doping in boron clusters can deviate substantially from an isoelectronic substitution process. We report herein on a unique sandwich di-Al-doped boron cluster, Al2B8, using global structural searches and quantum chemical calculations. The cluster features a perfectly planar B8 molecular wheel, with two isolated Al atoms symmetrically floating above and below it. The two Al atoms are offset from the center of the molecular wheel, resulting in a C 2v symmetry for the cluster. The Al2B8 cluster is shown to be dynamically fluxional even at far below room temperature (100 K), in which a vertical Al2 rod slides or rotates freely within a circular rail on the B8 plate, although there is no direct Al-Al interaction. The energy barrier for intramolecular rotation is only 0.01 kcal mol-1 at the single-point CCSD(T) level. Chemical bonding analysis shows that the cluster is a charge-transfer complex and can be formulated as [Al]+[B8]2-[Al]+. The [B8]2- molecular wheel in sandwich cluster has magic 6π/6σ double aromaticity, which underlies the dynamic fluxionality, despite strong electrostatic interactions between the [Al]+, [B8]2-, and [Al]+ layers.