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In the present work, biofuels produced from different raw fatty materials have been proposed as a dominant fuel component in...

Wheel-rail contact phenomena is problem considered in many scientific manuscripts. Mostly the research is focused on wear, friction and forces analysis. This paper presents research on rail vibration generated due to rail vehicle passage. The problem investigated was the influence of wheel slip phenomena on vibration of rail. The locomotive wheel slip can be caused due to braking, flat wheel or defect (wear) of rail surface. Therefore, results of presented investigations can be useful for many applications, including rail vehicle driving monitoring system, control system, especially due to braking distance or diagnostics of wheels of railway tracks. The research was taken place on experimental test track. For the complex analysis horizontal and vertical vibration were measured. The investigation requires regular train vehicle drive condition, where the wheels are rolling on the rail surface without wheel slip and second case for drive process including wheel rolling and wheel slip (friction rolling and sliding). The vibration signals are non-stationary thus its processing should be conducted simultaneously in the time and frequency domain, as time-frequency representation (TFR). For this purpose, Short Time Fourier Transform (STFT) and Continuous Wavelet Transform (CWT) can be employed.

The article presents the results of the technical state of shock absorbers on the stand with harmonic Eusam type kinematic forcing applied at vehicle inspection stations. As operating parameter, the pressure in the tires was assumed (assumed a reduced value in relation to the recommended nominal value) and the impact of this parameter on the values obtained during testing on the test bench was determined. The measurements were carried out several times. The results are summarized in tabular form and in the form of a graph and based on them final conclusions were formulated.

The article presents the results of noise measurements during a control passage recorded in the interior of a bus with a serial hybrid drive. The noise was recorded in a continuous mode, and the course was adjusted for the pressure level and spectrogram in the field of time and frequency.

The paper presents extended abstract on research on rail vibration caused by passing train. The purpose of the investigation was analysis of information capacity of vibration signal in case of different types of railway vehicles. The research was conducted on real rail track with regular operational environment. The measurement system consisted of three 3-axial vibration acceleration sensors and a data-acquisition device registering continuous waveforms of signals. The result analysis present shapes of the signals for separate periods and as comparison for different rail vehicles.

Passing rail vehicles generate vibrations and noise. In most studies, these phenomena are analyzed in terms of impact on people, the environment and railway infrastructure. However, using the vibroacoustic methodology, generated vibration and noise signals can be treated as information carriers. The vast majority of publications in the field of vibroacoustics analyze the usability of signals to determine the technical condition of machines and systems. For many years Professor Rafał Burdzik has been conducting research in the area of vibration and noise propagation analysis in means of transport. As a result of this work, a new research hypothesis was developed as the ability to identify a vehicle or trainset based on recorded images of vibroacoustic signals. The article presents the results of preliminary tests, during which rail vibrations were recorded in three orthogonal axes and acoustic pressure signals in the axis perpendicular to the railway route.

Diagnosing the technical condition of shock absorbers installed in automotive suspensions is a difficult issue due to the fact that these are elements of a complex mechanical system containing elastic and damping elements with nonlinear characteristics that degrade during operation. The paper presents the result of testing car with shock absorbers with programmed faults on the harmonic stand. The test object was a Fiat Seicento passenger car. The research experiment consisted in stimulating the vehicle to vibrations of forced masses, unsprung and sprung, and registration of vibration accelerations of these masses. The tests were subjected to shock absorbers with programmed faults in the form of loss of shock absorber fluid from 100% to 35% for rear shock absorbers. The acceleration of plates, swingarm (unsprung masses) and bodywork (sprung masses) were recorded by acceleration sensors. The results obtained in this way were subjected to wavelet analysis using the Morlet wavelet in the MatLab environment and based on these transformations the maximum of vibration amplitudes were determined depending on the degree of loss of the shock absorber fluid.

This article presents results of tests of the effect exerted by technical condition of shock absorbers on the braking efficiency of an automotive vehicle. The tests were conducted using Fiat Seicento featuring front shock absorbers which enabled shock-absorbing fluid-level adjustment. The tests comprised measurements conducted on the shock absorbers in four states, i.e. the nominal state with the fluid level at 100%, with shock-absorbing fluid levels of 25%, 50% and 75% as well as with the fluid tank completely empty (0%). Road tests of braking efficiency were conducted on cobbled pavement by means of a decelerometer.

This article provides a discussion on various solutions used in modern suspension systems of automotive vehicles. The mechanical dependent suspension system and some solution of adaptive, semi-active and active suspension system has been described. The paper also presents shortly test methods used to evaluation of technical conditions of this system.

The paper presents extended abstract on preliminary research on vibration employed for the trains traffic control. The research was conducted on experimental rail track with typical level crossing devices. The results present 3-axle distribution of vibration generated by the train simulator wheel-rail contact. For the sake of the numerical analysis of magnitude of the vibration the basic statistics have been calculated. The Fourier transformations of the signals presents the dominant frequency bands.

The paper presents results of measuring the force of the adjustment of the rail switch drive by spindle. The actuation force is the maximum force with which setting valve of the drive done to change position of the point. The simulation research requires proper mathematical model of the actuation force of the rail switch drive. Thus, the verification of such model requires real data measured on real object. The paper presents results of measurement and method of real data analysis.

Ensuring the reliability and durability of machinery and equipment, and above all, protecting people and the environment from the damaging effects of generated vibrations. This requires the use of effective methods and measures to counter their formation or spread. The vibroactivity of a machine (device) treated as an object can be changed in two basic ways. Parametric or structural modifications can be made. This study investigates the effect of on off temporary of shock absorber on vehicle suspension for vibration isolation.

The dominant sources of traffic noise, which are linked directly to the vehicle, are dependent on the speed. In terms of speed of 50-120 km/h the dominant source of noise is pneumatic wheels. The aim of the research was chosen to develop a method and experimental determination of the dominant frequency components of noise generated by the car tire. For the purpose of the study and on the basis of the analysis of the source data it was assumed that there is a relationship between the vibration of the tread elements and emitted noise, especially for low and medium frequencies. Thus, the target was set on the basis of the own method of research in the built measuring station. Based on the survey and the obtained results it can be stated that in the spectrum of the noise emitted by the tires the frequency components are dominant. Non-directional tire structure includes more frequency components which at the speed adopted in the studies are located at a greater frequency range than it is for the directional tire. In the case of a tire with a directional tread, acoustic emission energy is more associated with specific frequency components. The developed method provides results independent from the influence of the type of road surface on the acoustic emission while driving.

The article presents the results of simulation studies, the aim of which was to compare comparative energy consumption of short and long city buses in terms of assessing the needs for e-mobility. Currently, a number of e-mobility activities are observed, the largest of which has a dynamic change in the bus fleet structure and a significant, defined in subsequent years, increase in the percentage share of zero-emission buses (electric as well as hybrid and hydrogen). Decisions regarding the exchange of fleets should be preceded by proper analyzes, including the requirements and energy consumption of individual bus lines with the assumption of a certain number of passengers and the selection of a bus with proper capacity. The methodology for calculating energy consumption and determination of the required engine power presented in the article enables dedicated analyzes depending on driving profiles and specific bus parameters.

The paper presents High Mobility Wheeled Platform as example of new generation of military vehicles. It describes different types of special purpose vehicles with innovation direction of development. The concept of the article based on comparison of requirements and properties of wheeled platforms and special purpose vehicles. Thus the evolution of wheeled platform has been also presented. As the result of analysis and example of application the High Mobility Wheeled Platform was described.

This paper provides an analysis of a solution proposed for the design of the chassis of a special-purpose vehicle’s mobile platform using an example of the high mobility wheel platform (KPWM) manufactured by the company Szczęśniak Pojazdy Specjalne. The basic requirements pertaining to vehicle chassis are related to requirements concerning mechanical strength and lightness of structures, being difficult to satisfy at the same time. The suspension system used in the high mobility wheel platform in question represents a typical design, comprising a frame made of high-strength steel and based on stringers. The high mobility wheel platform’s suspension system uses reinforced parabolic leaf springs and half-elliptic springs as the elastic elements, whereas shock absorbers and stabilisers as the damping and propelling elements, aimed to reduce tilts of the vehicle body while driving in a curvilinear track. By shifting the front driving axle towards the front vehicle section, a higher approach angle could be obtained. On account of difficult operating conditions and for off-road driving purposes, specific solutions have been applied to protect the vehicle chassis against damage when moving in difficult terrain. Moreover, bearing in mind the vehicle’s intended use in military operations, where unplanned repairs of chassis components must often be conducted in the field, the designers have taken the necessity of using a very limited set of tools into account.

The article addresses results of analyses of design solutions and materials commonly used in gas springs for hydropneumatic suspension systems. The authors have discussed main advantages resulting from application of such a design solution in passenger car suspension systems. Fundamental correlations defining the parameters characterising a gas spring with constant gas mass have been referred to. Also materials used in the manufacture of selected gas spring elements have been described

The article addresses a method proposed for comprehensive research of vibration properties dedicated to new structural materials. The method in question comprises three-stage studies, thus enabling the related costs to be reduced on each stage of the process. Subjects of identification and assessment are both the properties and the material structure as well as numerically determined dynamic characteristics and actual vibration characteristics of materials. The article provides preliminary research results obtained for Cu-2Ti-1Co and Cu-6Ti-1Co alloys, the mechanical properties of which are very prospective. An additional advantage of the method proposed is the capability of identifying alloy types by application of non-destructive vibratory methods.

Autogenous laser welding of 0.8 mm thick butt joints of car body electro-galvanized steel sheet DC04 was investigated. The Yb:YAG disk laser TruDisk 3302 with the beam spot diameter of 200 μm was used. The effect of laser welding parameters and technological conditions on weld shape, penetration depth, process stability, microstructure and mechanical performance was determined. It was found that the laser beam spot focused on the top surface of a butt joint tends to pass through the gap, especially in the low range of heat input and high welding speed. All test welds were welded at a keyhole mode, and the weld metal was free of porosity. Thus, the keyhole laser welding of zinc coated steel sheets in butt configuration provides excellent conditions to escape for zinc vapours, with no risk of porosity. Microstructure, microhardness and mechanical performance of the butt joints depend on laser welding conditions thus cooling rate and cooling times. The shortest cooling time t8/5 was calculated for 0.29 s.

The article provides a discussion concerning the potential for applying advanced methods of vibroacoustic signal processing for the purposes of identification of a combustion engine state. It contains example results of vibration measurements on the passenger car combustion engine in three directions. The research was conducted on stopping vehicle, for different pre-set values of the engine rotational speed. The results of preliminary tests focused on the potential use in the diagnostics of engine operation.

The paper presents concept of engine vibration monitoring system dedicated for all kind means of transport. Based on nature of vibration phenomena the scope of the possibilities of usage of vibration become very wide. The procedure of vibration measurements allow to conduct constant registration without invasion into construction into mechanism. These are non-destructive methods. Due to all these advantages and very difficult environment of engine in means of transport the application of vibration methods for engine monitoring system become very popular. The paper presents some exemplary results of vibration registration on the block of the engine.

This paper addresses a study undertaken to develop spatial numerical models of a piston, a piston pin and a connecting rod with reference to real components of a combustion engine crank system. The numerical studies conducted comprised an analysis of how the mechanical strength of piston pins was influenced depending on the change in their inner shape. For the purposes of calculations, various scenarios of shape modification were proposed for piston pins currently in use, enabling their weight to be reduced.

The vibration of a vehicle treated as an object can be varied in two basic ways. Parametric or structural modifications can be made. Applying parametric modifications is not always possible. Examples are the suspension of motor vehicles. Changing the elasticity factor is limited by the allowable deflection arrow for different loads. Structural modifications are used for vibration isolation or vibration elimination. Vibro-isolation tasks are somewhat contradictory and practically impossible to achieve in passive systems. The alternative is to use in the suspension system elements with adjustable characteristics. On the vibrations object of the specified mass acts on the control signal. The control signal has a force dimension. This force is produced by a vibration isolator for which vibration parameters are input signals. The control force is the weighted sum of the forces of elasticity and damping. These components of the control force are proportional to relative displacement and relative velocity, respectively. In the developed concept of autonomous vibration damper, a control algorithm is applied which deactivating damper if the damping force influences the increase acceleration of the object’s vibration.

The paper presents results of research on influence of fatigue metal damage of the inner race of bearing on vibration in different frequencies. The active diagnostics experiments were conducted on application of vibroacoustics methods for technical condition monitoring. Provides an overview of materials and process analysis of rolling bearings wear. The bearing damage of the inner race have been simulating. The research was conducted on special research-educational test bench for vibration monitoring for rotaring machinery. For the identification of the symptoms of the defects in the vibration signal the analysis of time realization and frequency transformation of the vibration have been conducted. For the comparison of the vibration of good and damage bearings signals registered for different frequencies have been presented in form of spectrograms and RMS distributions.

The paper provides an analysis of the reasons for excessive wear of the camshafts system components based on models developed to describe the impact of selected material, technological and operational factors. The subject of the research was wear of camshaft cams studied in accordance with results of operation tests. Based on the said tests, the dependence of wear intensity of cams from their angular position was established. The respective calculation results enabled the function of cam fallibility to be determined.

The paper presents results of the active diagnostics experiments on influence of fatigue metal damage of the inner race of bearing and unbalance of rotating masses on vibration generated by the machine. Analysis of vibration related phenomena is a solution commonly applied in Structural Health Monitoring (SHM) systems. The application of vibroacoustics methods for technical condition monitoring has been developed in the past years in many systems of manufacturing processes. Vibroacoustic methods, based on the analysis of vibration or acoustic signals perceived as residual processes of non-invasive nature, is becoming more and more important in this respect. The scope of its application as well as the applicability of methods in numerous diagnostic systems also results from the capabilities of advanced methods of signal analysis and identification of numerous characteristics of technical condition. One of the most common operation damages are caused by rolling bearings wear. The scope of research contains tests on bearing damage and the unbalance of disc. The wear processes and unbalance are closely related to the vibration levels (arising from the mass loss of plastic deformation, and the fatigue damage). The research was conducted on special research test bench for vibration monitoring for rotating machinery. Structural health monitoring of machinery has to be conducted in different states and working conditions of the manufacturing system. Thus for simulating of different operating conditions the experiments have been conducted during run up of the machine which consist the transient states of working and during work on constant rotational speed of the power generate engine. For the identification of the symptoms of the machinery and equipments health monitoring the vibration signal have been analysed in time domain and frequency transformation as well. The performed signals are not stationary. Thus it is better to observe the signal simultaneously in time and frequency domains. For this purpose the spectrograms were determined. Spectrograms computes the short-time Fourier transform of a signal by default divided into segments. During the transformation the Hamming window and noverlap were used. For the comparison of the vibration of good and damage bearings signals registered for different frequencies have been presented in form of spectrograms and RMS distributions.

The paper presents results of investigation of car suspension system dynamics. In this research the multibody (Multi Body System - MBS) system software MSC.Adams was used. ADAMS software (MSC.Software) is a commercial software to build a multibody structural models. Modular design allows for the usage of applications with different focuses, such as rail, aviation and motor vehicles. Models with a large number of freedom degrees of the components are built with mass concentrated on the assumption that the system is composed of a rigid (or deformable) bodies combined in a specific way (connection spherical, sliding, rotary), moving under the action of the forces and moments of different types (concentrated or distributed forces, the forces of contact). The complex multibody systems are automatically generated by the Lagrange equations of motion of the second kind in absolute coordinates. Integral procedures used to solve the differential-algebraic equations include multistep algorithms with variable row and a variable-and fixed-step and one-step algorithms. The Adams/Car module enables building and simulation-based examination of individual car subsystems such as, for instance, the suspension, steering or driving system as well as their combinations forming a complete car. The programme contains an extensive library of structural solutions applied in cars. The geometry and relationship data of individual components are stored in libraries, and software operation on a standard user level can be brought down to defining positions of constraints in space. The software is compatible with various CAD programmes, thus enabling import of elements created in other applications. The study was conducted for the vehicle model of Fiat Seicento. The examined system of the complete vehicle consists of 49 kinematic degrees of freedom. The article examined the impact of chosen parameters on vehicle vibration in an Adams Car Ride. Used in simulation Adams/Car /Ride module allows to test vehicle dynamics forcing the position of the plate of test stand . Virtual model of the vehicle is set on four servo-motors. They can control any excitation combination of individual actuators (dispalcement and amplitude, phase between extortion, etc.) and determine all kinds of vibration (vertical, lateral, angular). The study was conducted for selected parameters of the test rig.

The paper presents the possibilities of application of vibroacoustic methods for monitoring and control of comfort and safety of passenger cars. It is described the WSA program for vibration signals processing. The paper presents some results of prototype experimental research and conception of the monitoring and control of comfort and safety system. The results of the WSA modules can be the input signal for the damping properties control system integrated with mechatronics system of vibration absorbing elements of suspension or engine and powertrain system mounting and springing elements.