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In this work, the authors focused on analyzing the energy efficiency and dynamics during car acceleration, featuring investigation of acceleration dynamics under various acceleration intensities. The tests were performed in the speed range between 45 km/h and 120 km/h, at a constant gear ratio. This enabled obtaining variable dynamic parameters of the acceleration process, ranging from about 0.1 to 1.4 m/s2 , and recording variation in fuel consumption from 6.28 to 27.03 dm3 /100km. The study focused on determining the relation between fuel consumption, energy efficiency and vehicle acceleration depending on the available drivetrain power. The relation between fuel consumption and vehicle acceleration was described by using the dynamic index. The proposed dynamic index takes into account the energy (from burned fuel) and vehicle acceleration intensity to obtain an objective metric for characterizing the acceleration process. The aforementioned index takes the form of the passenger car movement energy quality index and can be related to widely known physical properties, thus ensuring its universality. The index expresses the energy expenditure within the time needed to accelerate a vehicle weighing 1kg by a 1m distance. As opposed to other criteria that are applied to the assessment of passenger cars dynamics, the index shows a high determination coefficient R2 in excess of 0.99, and can be used as a universal metric to test other vehicle types.

The article provides a discussion on a methodology intended for testing of power transmission systems featuring an innovative highly torsionally flexible metal clutch patented by the co-authors of this paper. What this methodology takes into account is the amplitude and frequency analyses discussed in the article, as well as a sensing system based on diverse piezoelectric and magnetic phenomena, the Doppler effect, etc. Both contact and non-contact (laser measurement) methods were used during the tests. The purpose of the tests conducted at the stand, originally designed by the authors in accordance with the methodology proposed, was to evidence that using the innovative and patented, highly torsionally flexible metal clutch makes it possible to reduce the vibrations of multi-stage toothed gears, consequently reducing the forces affecting the gear bearings and those acting at the tooth space, which is to enable the service life of individual components of the power transmission systems intended for mining scraper conveyors to be significantly extended. Based on the studies and analyses performed by the authors, one can observe and conclude that the methodology proposed in the paper makes it possible to use an example of a relatively complex power transmission system in order to examine the relationships between the processes at work, i.e., the decline of the linear vibrations of the gear housing (which is undoubtedly positive in power transmission systems) at the expense of increasing torsional vibrations of the innovative clutch, the latter not to be considered unfavourable to users in the case analysed.

The paper presents novel methodology for multidimensional analysis of strongly nonstationary signals. This methodology contained the identification of working cycles, dedicated signal processing methods for each of identified segments of signal as time, frequency and TFR distributions of each signal segments. It allows to observe influence of increase of defects based on narrow and precise resonances windows. At the final stage of the signal processing the multidimensional estimators as representations of time, frequency and TFR measures are identified. The paper presents result of investigation conducted on real passenger car. It presents results for the signal processing of unsprung and sprung mass of suspension system separately. This approach allows to evaluate the properties of suspension and influence of the shock absorber defects on safety and comfort of the driving. The obtained results show a very good separation properties of multidimensional estimators for different kind of defects. Thus it can be considered as diagnostics method for condition monitoring of vehicle's suspension system.

The purpose of this research was to analyze the possibilities for the application of vibration signals in real-time train and track control. Proper experiments must be performed for the validation of the methods. Research on vibration in the context of transport must entail many of the different nonlinear dynamic forces that may occur while driving. Therefore, the paper addresses two research cases. The developed application contains the identification of movement and dynamics and the evaluation of the technical state of the rail track. The statistics and resultant vector methods are presented. The paper presents other useful metrics to describe the dynamical properties of the driving train. The angle of the resultant horizontal and vertical accelerations is defined for the evaluation of the current position of cabin. It is calculated as an inverse tangent function of current longitudinal and transverse, longitudinal and vertical, transverse, and vertical accelerations. Additionally, the resultant vectors of accelerations are calculated.

The paper presents how an important aspect of introducing new machines, especially in the mining industry, is testing a prototype under laboratory conditions. For this purpose, advanced methods of analyzing the vibrations of a drive system equipped with an innovative prototype of a flexible torsion clutch are presented. The main goal is to present a comprehensive method for analyzing vibration signals in various dimensions of the signal analysis. As a result of this approach, it can be seen how much important information about the tested clutch can be obtained by using various analysis methods in terms of time–frequency distributions or order analysis. To emphasize the differences in the functioning of the tested clutch and the possibility of monitoring these differences on the basis of the observation of residual processes, such as vibrations, the results for the flexible and locked clutch are compared.

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 human vibration is a multi-disciplinary subject involving many disciplines. A special area in the field of vibration research is the transport system. The paper presents the results of preliminary tests, the aim of which was to analyze the propagation of vibrations forced by the movement of the vehicle floor on persons sitting in a car. During research vibration were registered in measurement nodes, in which the composition always included the signal of oscillation of the enforcing plate and specific locations on the human body. This paper presents results of vibration recorded on the extinction plate and on the head of the passenger.

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.

The article presents an extended summary regarding the impact of rail damage on vibration waveforms and vibroacoustic spectrum images of vibrations. The analyzed example is based on the passage of the train depot – passenger train on a selected railway line. A short summary of the analyzed research problem is also presented.

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.

Safety of the railway transport is extremely important issue, thus it has to be supported by numerous of terms. It is not only the legislation and organization or traffic control but also the proper quality of every devices in the railway infrastructure. The paper deals with safety in the rail industry. Companies and producers of railway equipment have to guarantee the best quality, maintenance and reliability. Safety is also a device directly responsible for protecting e.g. level crossings but also safety in terms of design and construction. . Supervision of products is fulfilled in Poland by e.g. the Office of Railway Transport managing the safety and regulation of rail traffic. The paper presents industry security in terms of product as safety in design and production, in construction, in exploitation. Despite such extensive, multisector and multifaceted organizational, legal and technical safety structures in rail transport it is advisable to conduct further research into the analysis of the possibilities for improved safety. Also authors have assumed that for the improving of railway crossing safety level the support system for the traffic detection can be developed. To increase of the complex crossing safety level the support system has to be independent from current usage control devices, as axle counter block. Thus the paper presents concept of application of vibration wave propagation employing as source if information on train or car detection.

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.

This article aims are presenting the hazards arising from the direct contact of people with moving rail vehicles as well as the safety and consequence of human contact with the drag caused by the railroad system. This is the review paper with intended to illustrate and further analyze the risks, as well as to identify ways to identify such risks so that they can be counteracted.

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 paper presents extended abstract on preliminary research on influence of impulse force on vertical vibration of the rail. Research method was the impulse method for measuring the vibration response at specific points of track. It presents the waveforms of the vibration for the different distance from sensor to impulse point and distribution of the maximum and RMS values.

The paper presents novel method for research on exposure to nonlinear vibration of passenger car suspension as nonlinear dynamical system. Also paper provides a discussion on the results of studies addressing the impact exerted by damping properties of shock absorber on the vibrations being generated. The research was conducted on the car forced to vibration by the exciter machine with changeable frequency. The paper addresses results of analysis of application of one of the time-frequency representation techniques to the identification of structure of vibration. The obtained representation of the vibration allows determining time function of separate frequency bands, which represents the isolated vibration dynamics phenomena. Considering the variability of the time and frequency distribution of the vibration even in selected analysed bands, the time function was developed as exposure to vibration estimator. The recommended method makes use of function of exposure to vibration. The advantage of these method is possibilities of precise analysis of chosen frequency bands. The investigations conducted confirm considerable susceptibility to changes in the technical condition of shock absorber with regard to the assessment of human exposure to vibrations.

The paper presents the results of preliminary rail vibration tests generated by the passage of a rail vehicle. As part of the study, vibrations were recorded in three orthogonal axes, analyzing longitudinal, transversal and vertical vibrations. The results show time waveforms, signal spectra and time-frequency distributions. On the basis of the analysis of each of the forms of signal presentation, various vibration properties and interrelationships between propagation axes can be observed.

The article elaborates upon a study of the phenomenon of microsleep in drivers operating means of collective public transport on a regular basis. The microsleep phenomenon has been observed as a rather common one among drivers in general, however, in the case of professional drivers operating public transport lines, this is particularly dangerous. The consequences it may trigger are not limited to traffic accidents, but may even include road traffic disasters. The study addressed in the article was conducted using the eye tracking technique supported by auxiliary testing apparatus, including systems of the authors’ own design and make. The study was conducted in operation of different means of collective transport on public transport lines in Poland. In one case, microsleep was studied in a driver of the EN57 passenger train, while the second case studied was that of a driver of the Solaris Urbino bus. The data retrieved from the measurements were processed using the SMI BeGaze 3.4 software. Results of the studies, subsequently processed in statistical terms, were used to formulate operational conclusions concerning the microsleep phenomenon and to define specific recommendations for drivers of means of collective public transport based on such grounds. The article also touches upon the matter of the values of parameters characterising the phenomena of microsleep and blinking, as previously commented in the literature of the subject.

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 subject matter of vibrations in railway transport is still an ongoing cognitive issue. In terms of an increase of speed, size, as well as weight of rail vehicles, the scale of effects of vibrations generated when a train moves also grows. However, the authors decided to conduct research and analyze vibrations in a different approach. The article presents the results of the research which aim was to identify the vibration environment of the railway infrastructure. In order to do this, the research on a test track equipped with typical devices of the railway infrastructure, such as crossing signaling devices, point machines was conducted. Additionally, certain experiments were conducted in the environment of other railway occurrences as result of which vibrations are generated. Experiments of a vehicle passage through a level crossing were performed and a passage of a light rail vehicle in a form of a two-axle bogie was simulated. This research aims at analyzing the forms and distributions of vibrations in respect of a possibility to separate signals in the actual environment in which they occur and where often several forced vibrations overlap.

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 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.

Rail vibration signals are complex data represent different phenomena occurred by the wheel-rail contact or others excitations in railway infrastructure. Such signals can be considered as source of interesting information or unwanted degradation or annoying effect. Thus proper analysis of rail vibration signals are important task for the engineering research. The paper presents results of the preliminary analysis of rail vibration signal time and frequency structures generated by different mechanisms. The research assumption was to generate vibrations in the railway rail as a result of various dynamic interactions, which arise as a result of exploitation of the railway infrastructure and vehicle traffic, including the passage of the car through the railway crossing. The aim of the research was to compare the amplitude and frequency of vibration signals and to analyze the possibilities of determination of distinguishing features from different sources signals of vibrations as forced mechanisms. In order to analyze the propagation properties of the vibration wave during the experiments, signals were recorded in 3 perpendicular axes, as carriers of information about longitudinal, transverse and vertical waves. As a result of the conducted research, data sets were collected as orthogonal vibration signals generated by rail vehicle passage and the car passage, by switching of the point mechanism and as a result of single impulse of force, as an example of repair work on the tracks. Further research will be conducted towards statistical analysis of the collected data sets and the use of dedicated signal processing methods.

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 study involved measurements of surface tension of liquid binary copper-bismuth alloys with respect to their chemical composition and temperature as well as investigations of the liquid alloy - refractory material - gaseous phase system wettability using usual refractory materials, i.e. aluminium oxide, magnesium oxide and graphite. The experiments were performed with the use of sessile drop method and a high-temperature microscope coupled with a camera and a computer was utilised.

In the paper, results of the study on aluminium evaporation from the Ti-Al alloy (6.5%mass) during smelting in a vacuum induction furnace (VIM) are presented as well as the kinetics of the process is discussed. The experiments were performed at 51000 Pa for 1972 K and 2023 K. Based on the determined values of aluminium overall mass transfer coefficient, the mass transfer coefficient in the liquid phase and the evaporation rate constant, the stages that determined the investigated process were defined. It was demonstrated that Al evaporation from the aluminium-titanium alloy is kinetically controlled.