Wheel Vibration Research Articles

An analytical study of wheel regeneration in surface grinding

Machining vibrations have been a topic of active research since the beginning of the 20th century, because of their harmful potential to deteriorate the surface finish of the workpiece, reduce the lifetime of the machine tool and limit the overall productivity of manufacturing operations. Grinding, often being a finishing operation responsible for the final quality of the workpiece, can be especially affected by unwanted process vibrations. Machining vibrations can arise from a number of sources, but they are usually classified as forced and self-excited vibrations. Forced vibrations, such as those resulting from runout or unbalance, are generally easier to avoid. However, self-excited vibrations, also known as chatter, originate in the machining process itself and are typically more difficult to predict and suppress. When it comes to grinding operations, chatter can occur as a result of uneven surface regeneration on both the wheel and the workpiece. In this paper we perform an analytical study of grinding chatter, to explore the intricate nature of wheel regeneration (i.e. chatter arising from uneven wear on the wheel) in surface grinding. Whilst there has been a great deal of previous research into grinding chatter, the present study explores a contrarian approach whereby a circumferential variation of the specific grinding energy occurs during the onset of instability. The specific energy is a fundamental quantity in grinding that relates the necessary grinding power to the prescribed material removal rate. It is also related to wheel wear and thus to grinding forces, since a worn wheel requires more grinding power and produces greater grinding forces to sustain the same material removal rate than a sharp one. Therefore, by characterising the specific energy variation around the circumference of the grinding wheel as a function of wheel vibration, we derive a stability model and discuss its practical potential.

Rail Corrugation Detection of High‐Speed Railway Using Wheel Dynamic Responses

Rail corrugation often occurs on the high‐speed railway, which will affect ride comfort and even the train operation safety in severe condition. Detection of rail corrugation wavelength and depth is absolutely essential for maintenance and safety. A novel method using wheel vibration acceleration is proposed in this paper, in which ensemble empirical mode decomposition (EEMD) is employed to estimate the wavelength, and bispectrum features are extracted to recognize the depth with support vector machine (SVM). Firstly, a vehicle‐track coupling model considering the rail corrugation of high‐speed railway is established to calculate the wheel vibration acceleration. Secondly, the estimation algorithm of wavelength is studied by analyzing the main frequency with EEMD. The optimal parameters of EEMD are selected according to the orthogonal coefficient of decomposition results and the distribution of the extreme points of signal. The depth detection is transformed to a classification problem with SVM. Bispectrum features, which are extracted from the reconstructed signal using the high‐frequency components of wheel vibration acceleration, combining with train speed and corrugation wavelength are input into SVM to recognize the rail corrugation depth. Finally, numerical simulation is carried out to verify the accuracy of the proposed estimation method. The simulation results show that the proposed detection algorithm can accurately identify rail corrugation, the estimation error of rail corrugation wavelength is less than 0.25%, and the classification accuracy of rail corrugation depth is more than 99%.

Experimental Analysis for the Vibration Reduction of Steering Wheel Assembly of Agricultural Tractor

Steering wheel vibration is one of the primary contemplations in choosing the operator comfort in a agricultural tractor. This project manages investigation of vibration related issues in controlling wheel of tractor. The design and investigation of controlling system plays a major part to determine the main cause for the issue. Steering vibration study conducted on power trac 439 DS. Tuned mass damper idea is utilized for vibration decrease. various damping materials are tried for vibration lessening and analysis is done in MATLAB Simulink with two degree of freedom model with base excitation. After providing the isolation between steering box and steering wheel, the vibration level in the tractor is essentially reduced and the operator additionally feel more comfort as the HAVS are likewise reduce because of utilization of isolation. The vibration in the steering wheel of agricultural tractor can be decreased by the utilization of damper

НЕОБХОДИМОСТЬ НАУЧНО ОБОСНОВАННОГО ВЫБОРА СЕРИИ ПРОФИЛЯ ШИН ПРИ ИХ ЗАМЕНЕ ДЛЯ ОБЕСПЕЧЕНИЯ БЕЗОПАСНОСТИ

PURPOSE. The purpose of the paper is to justify the need for a scientific selection of a series of tire profiles when replacing tires in order to ensure vehicle safety. METHODS. The study uses the methods of mathematical statistics, mathematical modeling and provides a detailed analysis of the scientific and technical documentation on the topic of the research. RESULTS AND THEIR DISCUSSION. The article presents the statistical data on the wear of tire protector and shock absorbers and provides the criteria for the critical threshold of their life. Description is given to the selection features of lower series tire replacement. The results and analysis of comparative tests on the evaluation of shock absorber wear effect on the braking length of vehicles equipped and not equipped with ABS and ESP systems are presented. A formula is given for determining the conditional probability of the coincidence between the road accident and vehicle movement with wheel breakaways from the road. The results of calculations by the formula are presented as well. It is concluded that this probability can be more than 20% for road conditions in the territory of the Russian Federation. The amplitude-frequency characteristics of the relative accelerations of the vehicle body and wheel movements are constructed and analyzed. It is noted that the replacement of worn tires with the tires of a lower profile even if shock absorbers are serviceable significantly raises wheel vibrations (2 times), which increases the likelihood of wheel breakaway from the road and reduces the safety of motor vehicles. CONCLUSIONS. It is necessary to develop a methodology for scientifically based selection of a tire profile series when replacing tires taking into account the condition of shock absorbers in order to improve the safety of motor vehicles.

Longitudinal vibration of a resilient wheel under the adhesion limit

In order to study the longitudinal vibration law of a resilient wheel under the adhesion limit of different working conditions, two longitudinal vibration models of the resilient wheel of a motor vehicle are established, and the vibration laws and influencing factors of the resilient wheel under different operating conditions are studied by simulation. The model of the resilient wheel under low-speed driving and low adhesive operating conditions is established based on the Fastsim wheel/rail contact theory, and the other high-speed model of the resilient wheel is established by considering adhesion curve negative slope characteristics based on the Polach wheel/rail contact theory. The results show that at low-speed driving conditions, the longitudinal vibration of the resilient wheel is more violent than that of the solid wheel, and the sliding vibration of the resilient wheel at the adhesion limit is far greater than the nonadhesion limit at low-speed driving conditions. When the rail surface is polluted and the adhesion coefficient is low, with the speed increasing to 80 km/h, stick-slip vibration occurs on the resilient wheel due to the increased vibration between the wheel rim and the wheel hub. Under high-speed conditions, owing to the negative slope characteristic of the adhesion curve, the wheel adhesion recovery time decreases with the reduction of driving torque. The amplitude of vibration for the above two conditions increases with the increase in the stiffness of the motor boom and the longitudinal stiffness of the primary suspension. With the increase in the value of the radial stiffness and torsional stiffness of the resilient wheel, the vibration amplitude of the resilient wheel becomes smaller or suppressed. The vibration of the resilient wheel is transmitted to the frame through the primary suspension, which has little effect on the vibration of the vehicle body.

Response Sensitivity to Design Parameters of RV Reducer

Dynamic characteristic significantly affects performance of RV reducer. The current researches mainly pay attention to free vibration properties of RV reducer. In order to satisfy the increasing demand on high performance, response sensitivity is analytically studied on the basis of cyclic symmetry structure. Based on the structure characteristics, a dynamic model is developed by taking into account the influence of bearing stiffness, crankshaft bending stiffness and mesh stiffness within planetary and cycloidal stages. For the model, governing equation of motion is derived and solved by Fourier series method. The solution revealed that forced vibrations at primary frequency are well defined structural. There exist three typical forced vibration modes: rotational, translational and planetary component modes. Response sensitivity to basic design parameters is obtained as closed-form expressions by differential method. With the typical vibration modes, response sensitivity is simplified and classified into three types. Calculation of sensitivity implies that vibrations of the output wheel are sensitive to eccentricity. As eccentricity increases, sensitivity of translation decreases first and then increases, but sensitivity of rotation always increases. The proposed method for analyzing response sensitivity provides some principles for selecting parameters for RV reducer from the point of view of forced vibration.

Effects of Rotor Position Error on Longitudinal Vibration of Electric Wheel System in In-Wheel PMSM Driven Vehicle

The influence of a rotor position error on the longitudinal vibration of an electric wheel system is analyzed. To begin with, the influence of the rotor position error on the motor current and torque is deduced using coordinate transformation. The results show that the rotor position error will induce current harmonics, which cause further torque ripples with frequencies of kp res/ pfe and (6 ± kp res/ p ) fe ( k = 1, 2, 3, p is the number of motor pole pairs, p res denotes the number of resolver poles, and fe indicates the current fundamental frequency). Then, the dynamic model of the electric wheel is established, and the main vibration modes are determined. A comparative analysis of the motor's longitudinal vibration response with and without the rotor position error shows that the torque ripples with frequencies of kp res/ pfe deteriorate the vibrational characteristics of the electric wheel system over the entire working range. The torque ripples with frequencies of (6 ± kp res/ p ) fe increase the motor's vibration at low rotation speeds. Next, the influence rules of rotor position error on the current harmonics and longitudinal vibration are verified by electric wheel bench test. At last, a control method based on adaptive Kalman filter is proposed. This method can mitigate the adverse effects of the rotor position error according to the experimental results. This study provides a reference for the diagnosis of the motor rotor position error and the attenuation of electric wheel vibration.

Three-dimensional modelling and simulation of vibration marks on surface generation in ultra-precision grinding

Nowadays, most modelling work for ground surface topography is based on either abrasive kinematics (micro-level) or high-frequency vibration of the grinding wheel (macro-level) to predict surface quality or grinding performance, but there is a lack of a correlation model to relate these two levels together. In this research work, wheel shape with two radii and wheel synchronous vibration are modelled first for the interference of the tool edge in 3D space to reveal the evolution mechanism of surface waviness under different vibration conditions (phase shift from 0.0 to 1.0). Hence, a multi-scale model is established considering the diverse protrusion heights of the grits and incorporating the wheel shape and micro-vibration of the tool so as to explain the mechanism of the generation of the surface marks on the ground surface. The result shows that four principal residual marks are formed on the ground surface including spirals, tool feed marks, cumulative phase marks and abrasive grain scratches. The amount of surface waviness resulting from the tool unbalance is equal to the ratio of the rotating speed of the grinding wheel and the workpiece. The feed mark representing the tool locus and tool nose geometry is a spiral pattern from edge area to the machined center. The phase shift marks are caused by the phase accumulation effect. The grit scratches are related to the wheel geometry, kinematics and distribution of protrusion heights. In addition, the phase shift tends to increase the density of grinding marks, with a significant decrease when the phase shift is equal to 0.5. The surface generation model is further verified by a closed surface matching method, which shows the simulation results agree reasonably well with the grinding experiments.

Analysis of the electric wheel vibration reduction system of a wheel-hub motor-driven vehicle

Based on the principle of multi-stage vibration isolation and active vibration absorption, a multi-stage passive vibration-isolating system and active motor vibration-absorbing system are designed for the electric wheel system of wheel-hub motor-driven electric vehicle, and the 1/4 suspension structural diagrams of the two vibration-isolating systems are drawn. Secondly, the corresponding multi-degrees-of-freedom vertical vibration model is established according to the different structural diagrams, and the dynamic differential equation of the multi-degrees-of-freedom vibration system is deduced. Then, by programming the MATLAB software is used to solve the acceleration of the vehicle body, the dynamic deflection of the suspension spring, and the amplitude, and the frequency characteristic curve of the relative dynamic load of the wheel of the 1/4 suspension system are drawn and the results are compared and analyzed. Finally, the ADAMS software is used for remodeling; the simulation experiment of ADAMS multi-body dynamics verified the correctness of the theoretical results of MATLAB software. The results show that the ADAMS simulation experiment results are consistent with the MATLAB theoretical results, and their correctness is verified. The vibration isolation effect of the active vibration-absorbing system is better and can improve the riding comfort and safety of the vehicle; hence it is worth popularizing and drawing.

An assessment of mode-coupling and falling-friction mechanisms in railway curve squeal through a simplified approach

Curve squeal is one of the most annoying types of noise caused by the railway system. It usually occurs when a train or tram is running around tight curves. Although this phenomenon has been studied for many years, the generation mechanism is still the subject of controversy and not fully understood. A negative slope in the friction curve under full sliding has been considered to be the main cause of curve squeal for a long time but more recently mode coupling has been demonstrated to be another possible explanation. Mode coupling relies on the inclusion of both the lateral and vertical dynamics at the contact and an exchange of energy occurs between the normal and the axial directions. The purpose of this paper is to assess the role of the mode-coupling and falling-friction mechanisms in curve squeal through the use of a simple approach based on practical parameter values representative of an actual situation. A tramway wheel is adopted to study the effect of the adhesion coefficient, the lateral contact position, the contact angle and the damping ratio. Cases corresponding to both inner and outer wheels in the curve are considered and it is shown that there are situations in which both wheels can squeal due to mode coupling. Additionally, a negative slope is introduced in the friction curve while keeping active the vertical dynamics in order to analyse both mechanisms together. It is shown that, in the presence of mode coupling, the squealing frequency can differ from the natural frequency of either of the coupled wheel modes. Moreover, a phase difference between wheel vibration in the vertical and lateral directions is observed as a characteristic of mode coupling. For both these features a qualitative comparison is shown with field measurements which show the same behaviour.

Numerical analysis for impacts of nozzle end-clearances on aerodynamic performance and forced response in a VNT turbine

It has been well known that nozzle end-clearances in a Variable Nozzle Turbine (VNT) are unfavorable for aerodynamic performance, especially at small openings, and efforts to further decrease size of the clearances are very hard due to thermal expansion. In this paper, both the different sizes of nozzle end-clearances and the various ratios of their distribution at the hub and shroud sides were modelled and investigated by performing 3D Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) simulations with a code of transferring the aerodynamic pressure from the CFD results to the FEA calculations. It was found that increasing the size of the nozzle end-clearances divided equally at the hub and shroud sides deteriorates turbine efficiency and turbine wheel reliability, yet increases turbine flow capacity. And, when the total nozzle end-clearances remain the same, varying nozzle end-clearances’ distribution at the hub and shroud sides not only shifts operation point of a VNT turbine, but also affects the turbine wheel vibration stress. Compared with nozzle hub clearance, the shroud clearance is more sensitive to both aerodynamic performance and reliability of a VNT turbine. Consequently, a possibility is put forward to improve VNT turbine efficiency meanwhile decrease vibration stress by optimizing nozzle end-clearances’ distribution.

Active disturbance rejection control for electric power steering system with assist motor variable mode

The steering torque of automobile EPS steering system is significant for driving steering control and good driving feel. Servo motor control and external interference moment are the core factors affecting EPS steering system. With the advancement of automotive technology, the requirements of EPS control technology have been gradually improved, and the driving and handling of vehicles at high speed have become the key issues. For the current EPS steering system at high speed vibration and steering feel, active disturbance rejection EPS torque control method is proposed, EPS variable mode controller was developed. The control of the variable mode is verified by experiment and the vibration torque from the road is controlled, determine the control frequency of 30 KHz, the amount of current fluctuation is the smallest. The ADRC (active disturbance rejection controller) technology is used to suppress the interference of the road surface, finally, the validity of active immunity is verified by bench test. Steering wheel vibration torque can be reduced by an average of 28.5% to 33.3%.

Analysis of Vibration and Sound Radiation Characteristics of Resilient Wheel in Metro

The wheel of vehicles is not pure rolling on the rail for the track irregularity, but with a small vertical and horizontal relative displacement. The relative displacement produces the wheel rail force and causes the vibration of the wheel and rail, which is transmitted to the air and produces noise. Therefore, it is of great significance to study the wheel's vibration and sound radiation under the track irregularity conditions. In this paper, the wheel-rail coupling dynamic analysis model of metro vehicle was established by using UM software and was researched by numerical calculation method, the wheel-rail contact force under irregularity excitation was obtained. Then the acoustic calculation model of the rigid wheel and the resilient wheel was established. Combined with the structural finite element method and the acoustic boundary element method, the structural response obtained by transient dynamic analysis was used as the boundary condition to study the acoustic radiation characteristics and the noise reduction effect of the resilient wheel. The study results show that under the vertical excitation of wheel-rail, compared with rigid wheel, the use of resilient wheel can inhibit the vibration for rim, tread and web. The vibration acceleration attenuation of the web is most significant, from 97m/s2 to 58m/s2. It is because of the vibration reduction function of the rubber body for the resilient wheel. The sound power level of the resilient wheel has a slight increase in the low frequency range and has a slight decrease in the high frequency range, in the whole calculated frequency range the sound power level of the resilient wheel decreases by 10.1 dB. These provide a good reference for the resilient wheel application in metro vehicle.

Multi-body Dynamics Analysis of the Axial-direction Vibration of Angular Contact Ball Bearing for Controlling the Infinite Vibration of Satellite Reaction Wheel

For satellite, it is necessary to reduce the vibration of rotating bearings in reaction wheel. In order to investigate the mechanism of the small vibration caused by bearings and its control scheme, we have conducted the multi-body dynamics analysis for angular ball bearing and reaction wheel. We focus on the effect of mechanical factors such as non-circularities of the inner and outer rings and the angle misalignment between them to the rotating secondary vibration component in the axial direction. It was found that the angle-misalignment enhances the rotating secondary vibration component when the inner ring involves second-order waviness. Also, axial-direction vibration is enhanced in the case that the waviness orders of inner and outer rings are coincident each other and angular-direction vibration is enhanced in the case that the difference in waviness orders of inner and outer rings is equal to 1 when the inner and outer rings involve the waviness. These vibrations are caused by the non-linear elastic contact between ball and raceway. Finally, from the parameter design, it was found that the effect of angular misalignment to axial vibration is greater than that of non-circularity of outer rings and these mechanical factors independently affect to the vibration.

Integration Design and Optimization Control of a Dynamic Vibration Absorber for Electric Wheels with In-Wheel Motor

This paper presents an integration design scheme and an optimization control strategy for electric wheels to suppress the in-wheel vibration and improve vehicle ride comfort. The in-wheel motor is considered as a dynamic vibration absorber (DVA), which is isolated from the unsprung mass by using a spring and a damper. The proposed DVA system is applicable for both the inner-rotor motor and outer-rotor motor. Parameters of the DVA system are optimized for the typical conditions, by using the particle swarm optimization (PSO) algorithm, to achieve an acceptable vibration performance. Further, the DVA actuator force is controlled by using the alterable-domain-based fuzzy control method, to adaptively suppress the wheel vibration and reduce the wallop acting on the in-wheel motor (IWM) as well. In addition, a suspension actuator force is also controlled, by using the linear quadratic regulator (LQR) method, to enhance the suspension performance and meanwhile improve vehicle ride comfort. Simulation results demonstrate that the proposed DVA system effectively suppresses the wheel vibration and simultaneously reduces the wallop acting on the IWM. Also, the alterable-domain-based fuzzy control method performs better than the conventional ones, and the LQR-based suspension exhibits excellent performance in vehicle ride comfort.

Numerical optimization for vibration and noise of the wheel based on PSO-GA method

Currently, those reported researches conducted optimal design for the wheel only in order to reduce the tread wear and increase the service life, but they did not consider the wheel vibration and radiation noise which seriously influence people’s life and did not achieve obvious noise reduction effects. Aiming at this question, a multi-body dynamic model of the high-speed train was established, and the vertical and radial force was extracted to input into the finite element model of the wheel to compute its vibration characteristics. Then, the wheel was conducted on a multi-objective optimization based on particle swarm optimization improved by genetic algorithm (PSO-GA) method. Finally, the optimized vibration results were mapped to the acoustic element model to compute the radiation noise of the wheel. The computational model was also validated by experimental test. In order to observe the optimized effect, the optimized results were compared with those of the traditional GA and PSO method. Solutions of the traditional GA and PSO method were relatively dispersed during iterations and the algorithm could easily fall into the locally optimal solution. The optimized results of PSO-GA method were obviously better. Compared with the original wheel, the vibration acceleration was reduced by 22.9 %, and the mass was reduced by 1.1 %. Finally, the optimized vibration was mapped to the boundary element model to compute the radiation noise of the wheel, and the computational results were compared with the original wheel. Radiation noises of the original wheel were obviously more than that of the optimized wheel, and there were a lot of obvious peak noises in the original wheel. Radiation noises of the optimized wheel only had two obvious noise peaks in the analyzed frequency. Therefore, a wheel with low noises and lightweight was achieved in this paper.

Wheel vibration estimation of railway vehicle utilizing state observer

Wheel vibration is one of the most crucial factors associated with the running safety of a train. How to detect and estimate it in real-time attracts significantly researchers’ interest recently? In this paper, a new method of estimating the wheel vibration of a railway vehicle utilizing a partial state observer is proposed. The partial state observer of wheel vibration estimation is designed based on the railway vehicle dynamic system model established in state space. Different kinds of track irregularities are considered as inputs for the vehicle dynamic system. Subsequently, the state responses of the car-body and the bogie frame obtained from dynamic simulation are used as the inputs of the partial state observer. The simulations were conducted at various running speeds of a vehicle. The results show that the partial state observer is capable of estimating well the wheel vibration using dynamic responses of the car-body and the bogie frame, and has a stable convergence, which leads to get consistent with the real dynamic system after duration of 0.15 s from starting system. This method thus would provide an innovative approach to estimate the wheel vibration of a real railway vehicle in real-time.

Analysis of Strength of Glass Fibre Composite Leaf Spring Using Finite Element Method

Leaf spring, as one of the main components of the suspension system, serves the function of absorbing road shocks and any wheel vibrations, preventing them from being transmitted directly to the vehicle body. Moreover, it can increase the tire traction as well as support the weight of the vehicle and various kinds of external forces. Various studies on the use of composite materials for leaf springs have shown that the strength of composite leaf spring is similar to steel leaf spring with the same load carrying capacity. However, the composite leaf spring has the added advantage of being more lightweight. In fact, composite materials have been preferable for many purposes not only because of its properties but also its lightweight structure and cost effectiveness. The analysis process was carried out using the finite element method by means of ANSYS software to display the output of the analysis being performed. After the output is known, the amount of voltage in conventional, mounted, and progressive spring can be determined. Based on the data analysis, we concluded that conventional straight leaf springs produced a maximum voltage of 653.13 MPa and maximum deflection of 4367.1 mm. The results of the analysis using the finite element method showed that conventional leaf springs (both straight and not) are considered as the most effective model of leaf spring in terms of the power generated.

An Analysis of the Vibrational Characteristics by the Contact with the Wheel-Rail and the Wheel Scratch in the Subway Train

The vibration of wheel is mainly affected by a fault on a wheel contacting with railway when average speed is over 60km/h. When the wheel vibration caused by wheel scratch increase more than a certain criterion, the wheel is shaved to reduce the vibration. This criterion of shaving is determined from the acceleration signal measured from the sensor mounted on the railway. In this study, vibration characteristics of the rolling wheels having a fault is analyzed with experimental approach to verify the acceleration criterion for shaving wheel.

Research on the Structural Transfer Path of New Mechanical Elastic Wheel Vibration

To explore the double buffer damping performance of a new mechanical elastic wheel vibration (MEW), the structural transfer path of MEW vibration was studied using the evaluation method of path transfer ratio and insertion loss. According to the transmission path of the wheel's exciting force, the model of wheel vibration transfer path system was established. Combined with the analysis results of modal test, the response of the each vibration transfer path system was analyzed quantitatively, and the contribution of each transfer path of the wheel vibration was qualitatively evaluated. The analysis results indicate that the two paths have higher transfer ratio in each order natural frequency, the transfer ratio and insertion loss of path 2 are greater than the path 1 in low frequency, the transfer ratio and insertion loss of path 1 are little with the path 2 in high frequency. The analysis results reflect the objective law of the actual vibration transfer characteristics of the MEW, and provide a reference for the MEW structure optimization.