Table of contents

The increasing emphasis on ecology by the governments of particular countries makes vehicle manufacturers to look for alternative sources of propulsion to meet increasingly stringent exhaust gas emission standards. One of such solutions is the use of a hybrid system in the form of a combination of a combustion engine and an electric motor. Such a combination, together with the possibility of recovering the kinetic energy during braking, makes the vehicle, comparing to the conventional drive, much more friendly to the environment. This technology poses the new challenges in the terms of operation, testing and diagnostic measurements of the hybrid vehicles. Because of the electrical system operating under a high voltage, many service and repair facilities are still afraid of repairing the above vehicles. In this article are discussed the basic safety and diagnostic procedures during vehicle tests on the example of the Toyota Prius of the second and third generation. The following procedures have been discussed: analysis of the operation of the high voltage battery with a diagnostic tester, the recommendations during measurements by means of an oscilloscope for low voltage sensors and the procedure related to disconnecting the power supply of the hybrid system in case of an accident. In addition, more and more specialised measuring devices, dedicated to laboratory units and services, appear in the market every year. Therefore, this article reviews the devices dedicated to repairs of vehicles with the hybrid and electric drive.

The purpose of the tests is to register signals that have a direct impact on the ABS system when braking and accelerating the vehicle. The purpose of the simulation tests was to analyse the influence of signals from the velocity sensors of individual wheels and the moment of recognition of the fault signalled by the ABS diagnostic lamp lighting up. The ESP system simulation was carried out on a specially designed and made test stand equipped with the ESP 5.3 system.

The work is devoted to the investigation of low-temperature properties of alternative jet fuels mixed with bio-additives derived from rapeseed oil, methanol and ethanol. For this work, a modification of conventional jet fuel from rapeseed oil, methanol and ethanol was chosen to develop alternative jet fuels. The main low-temperature characteristics – freezing point and pour point of conventional jet fuel and three types of bio-additives were identified and compared with the requirements for conventional Jet A-1 fuel. The influence of bio-additives from rapeseed oil, methanol and ethanol on low-temperature characteristics of new jet fuels has been studied and explained. The necessity of studying new technologies is grounded.

The article presents the results of tribological tests aimed at evaluating the resistance of protective layers of car paints to abrasive wear using the ball-cratering method. Substance1 and substance2 was applied by spraying it on previously prepared (in accordance with car body paint practice) samples. The tests were carried out on unprotected samples and samples with several types of protection using ceramic-based substances, which were produced using nanotechnology. The experiment was planned using Taguchi methodology. First, preliminary tests were conducted in order to build a orthogonal array. Then, using an ETA function, the optimal parameters for the actual experiment were determined. The results of the experiment show that the fifth group of samples (coated with four layers of substance2 and one layer of substance1) produced the worst results. Using this type of protective layer makes the coating more susceptible to frictional wear than not using any type of protection.

Piston – ring – cylinder is the typical and simple example of the friction pair that we can find in combustion engine where wearing is one of the main problem. Research on stability of friction pairs are focused on the surface and the top layer of surface in the parts. The main goal is find new solutions in design and materials in order to reduce wearing, which is consistent with the observed trend of technology development. This article presents one of the stages in the research of the newly developed piston ring designed for an internal combustion engine, in which the novelty is an innovative diamond-derivative coating with very good anti-wear properties. Objective of this work was to realize an endurance test in railway engine EMD645 based on rings with diamond coatings and a test of roll-block type on tribotester to set wearing and friction forces of specimen. The super-hard, anti-wear amorphic coatings based on carbon-like diamond show a promising direction in automotive industry, mainly in terms of decreasing friction coefficient in parts of internal combustion engine. The work aims to show the possibilities and benefits of the application of new protective coatings on structural elements.

The study presents research aimed at developing a decision model allowing to reduce Carbon dioxide emission to the atmosphere during corn harvesting for the needs of agricultural biogas plants. In order to develop this model, it is important to determine the optimal number of transport sets used during the transport process. It has been proved that it is possible to build a criterion function based on the time of transport (transfer to the place of loading, loading itself, transit to the place of storage, unloading), which results in the minimum number of transport sets used in this process. Presenting the possibilities of determining the optimum number of sets minimizing the set criterion function is the purpose of the study. The analysed criterion function represents the average cost (Carbon dioxide emission) per the time unit of the subject system composed of a forage harvester and transport assemblies.

The article describes the prototype neural network diagnostics model application to the driving active safety determination. The neural network fitting performance was used as an diagnostic indicator. The model used the two-layer-feed-forward network, including 10 sigmoid neurons in the hidden layer and linear output layer neurons. The model application example was involved with driving and braking with working ABS and ESP systems on snowy road. The 3-axis vehicle body acceleration, the speeds of wheels and the vehicle linear velocity were measured. Different kinds of tyres with various pumping pressures were applied. The measurements were obtained during the repeatable test runs. The diagnostic reference characteristics was chosen. The reference characteristics was involved with application the winter tyres with the proper pumping pressure level. The neural network was reproducing the data involved with the reference characteristics from the data involved with the test runs with inadequate tyre kinds or pumping pressure levels. The more weather-adequate the tyre kind and pumping pressure are, the smaller reproduction errors occur. Thus, the neural network reproduction error was used as an diagnostics indicator. The conducted analysis show the approach drawbacks, resulting from the vibrations and limited repeatability. The further steps, dealing with these problems, including the signal approximation methods, were proposed as the conclusions.

The subject matter of the publication concerns numerical analysis and empirical research on the strength parameters of thin-walled energy-consuming structures subjected to crushing, which include the front longitudinal of the vehicle. The influence of welding processes applied during post-accident repair on selected mechanical properties of repaired elements was investigated. The process of creating a half wave will be touched, as a result of local buckling of the profile which is characteristic for the fourth class cross-sections, responsible for the progressive course of deformation. The results of the numerical analysis were compared with the results of empirical studies for selected states of stresses. The strength tests of connections as well as the entire models are presented. The result of the above tests is an attempt to answer the question: whether the partial change of the front longitudinal, in the conditions specified by the vehicle manufacturer in post-accident repair technology of energy-consuming elements, restores the usable properties of strength properties to the original state.

The paper presents selected problems concerning the concept of automatic controlling of motor vehicle motion in case of sudden appearance of an obstacle. If the vehicle cannot be brought to a halt before hitting the obstacle and the adjacent lane is clear, circumvention of the obstacle is the only way to avoid a collision. In the concept of the vehicle control system, elements of general control theory and simplified models of longitudinal and lateral vehicle dynamics have been used. The vehicle controlling process consists of two stages: braking and then changing the lane at a speed determined by the braking stage. The first stage is implemented with using standard mechatronic systems that automatize the braking process, while the second stage requires the use of a special controller coupled with the steering system. The controller generates a "bang-bang" reference signal and corrects it by means of regulating systems that minimize the deviations of the actual (measured) signals describing vehicle's trajectory from the reference signal. The control algorithm developed has been based on very simplified and, thanks to that, efficient reference models. The algorithm was validated by simulation tests, where a model of a medium-size truck was used as the virtual controlled object. In the model (3D, nonlinear, MBS type, experimentally verified), a very detailed description of vehicle motion, even in boundary conditions, can be taken into account. The paper presents fragments of the research work, including unpublished results of computational tests.

Current vehicles are equipped with many sensors used to record traffic parameters. In addition, more and more drivers use video recorders that record the speed and location of the vehicle. The data can be used in modelling and reconstruction of the process of the incidents. The aim of the study is to assess the possibility of using the MATLAB environment for the reconstruction of road accidents by modelling the vehicle movement in a two-dimensional space. In further works, the models will be supplemented with an algorithm enabling calculations in a three-dimensional space. The assumptions necessary to create the 2D models were formulated. Then the numerical models in the MATLAB environment was applied. Several simulations were performed by testing the models' operation. The conducted analysis is to prove the legitimacy of using the model in the reconstruction of simple road accidents and predicting the behavior of the vehicle on the basis of given input data.

One of the basic tasks of the accident reconstruction is to define values of parameters of participants of the accident before its actual occurrence. The assessment of correct behaviours is made and the court decides whether the accident participants are guilty or innocent. Therefore, the credibility of specific values is essential. The use of so-called accident recorders – EDR/ADR type of devices, as an alternative compared to classical methods for accidents reconstruction – has become more common over the past years. The paper includes basic notions related to this type of devices, describes potential sources of uncertainty of the car motion reconstruction results, obtained on the basis of their records. Exemplary results of calculations made with simulation methods are presented (but using experimentally verified models).The examples presented confirm their usefulness, however, they also indicate possible significant errors in the motion parameters assessment if simplified devices are used.

The rapid development of automotive technology requires that designers should use modern materials. Materials used to construct the most heavily loaded components such as the components of internal combustion engines are often subjected to various treatments to enhance their mechanical properties. One of the well-known methods for modification of material in terms of tribological properties is ion implantation. The samples were implanted using manganese ions. The distribution of implanted ions and vacancies at various depths was calculated by the SRIM program. The implantation process was run with the energy E = 175 keV, and the dose of implanted ions was set to D = 5⋅10¹⁶ Mn⁺/cm² and D = 1⋅10¹⁷ Mn⁺/cm². Next, the samples were subjected to tribological tests on a pin-on-disc stand using the Nano Tribometer (NTR2) manufactured by Anton Paar. As a counter sample, we used a ball with a diameter 0.5 mm made of WC (tungsten carbide). A load of 0.5 N was applied to the ball. As a result, we determined variations in the friction coefficient for individual samples under dry friction conditions. Next, scanning electron microscopy (SEM) analysis was conducted using a Phenom ProX microscope. The wear trace was measured using the Taylor Hobson Form Talysurf 50mm Intra profile measurement gauge. The measurements provided profilograms facilitating determination of the mean wear and the depth of the wear trace. The implantation of manganese leads to a change in the friction coefficient and tribological wear of the Stellite 6 cobalt alloy.

Titanium and its alloys are commonly used in space, aviation, and motorisation industries due to their high strength and corrosion resistance. However, given its poor tribological properties (high friction and wear coefficients), methods for improvement of the tribological properties of titanium are continuously being developed. This study presents the effect of nitrogen ion implantation with energy 60 keV at a fluence of 1⋅10¹⁷ N⁺/cm² on changes in the properties of titanium alloy Ti Grade 5 (Ti-6Al-4V). Ion implantation was carried out through a mask with φ = 500 μm diameter holes. Nitrogen implantation through the mask improve the tribological properties of Ti6Al4V, by reducing the mean value of the friction coefficient and reducing tribological wear.

The article presents research on the wear between the bearing and journal surfaces. The investigation was done for two types of layers obtained by: laser drilling of EN-GJS-600 ductile cast iron and gas nitriding of 38 HMJ steel. Wear rates were defined on the base of comparison of surface layer profiles before and after the wear test. Comparing test results it was found that the biggest differences of the surface roughness parameter were obtained for gas nitrided specimens (ε + γ`+ α) while the smallest differences for the laser drilled ones. Moreover the surface layer of specimens was evaluated with the usage of microhardness measurements. The surface of the drilled specimens was characterized with the constant value for the melt layer. At the end of the paper findings of the research were summarized and the conclusions were drawn.

The paper presents the use of the evolutionary algorithm in the reconstruction of vehicle collisions to look for the point of the force impulse – Point of Impact (POI) and the Angle of the Tangent Plane (ATP) during the collision of two cars. The location of this point and the angle of the tangent plane of the collision are often decisive for the simulation of the vehicles' motion and the calculated pre-crash speeds. The simulation calculations have shown that the evolutionary algorithm allows the location of POI in the area of the highest energy consumption of a given collision. This is the area with the highest stiffness of the car's structure. The search for ATP has also been successfully completed. This allowed for a reliable calculation of vehicle pre-crash speeds. Calculations were validated based on the actual crash test. The presented quality and limitation functions (vehicle stopping area and track run) are based on checking whether the vehicle in the simulation movement has stopped at the place determined by the surface with given dimensions, and the trajectories of the wheels tracks coincide with the set corridors. The uncertainty of calculations is indicated.

The article presents the results of the research on the assessment of photobiological hazards caused by ultraviolet radiation and blue light emitted from low and high-beam headlamps with three different light sources: halogen bulb, xenon-arc and light emitting diodes (LED). The studies show that modern light sources used in automotive industry can be the cause of blue light retinal hazard. Tested headlamps with LED and xenon-arc sources are assigned to RG2 risk group according to to PN-EN 62471:2010, maximum exposure times are in range of 24-40 s and threshold distances 5.3-8.3 m. There are no ultraviolet radiation hazard caused by low and high beam headlamps except for xenon lamp. Obtained results were referred to photometric and colorimetric quantities of tested headlamps.

The paper presents results of an experiment taken to find out if the results of examination of selected subsystems performed in many technical inspection station (TIS) for the same car will be different and what will be a statistical dispersion of obtained results. Obtained results show that sometimes the results of examinations in different TIS stations are very different. For example, obtained coefficient of variation (CV) for results of braking force measurements has a value of around 20%, for EUSAMA coefficient obtained CV has value about 8% and for air-fuel ratio (λ) CV has a value over 60%. Some observations concerning also the correctness of examination procedures performed in tested TIS stations are presented in this paper. General conclusion for obtained results is that it is reasonable to require periodical technical inspections for test stands used in technical inspections stations.

Vehicles operating in dense traffic take their cabin air from the low diluted exhaust gas cloud produced by other cars or trucks running ahead of them. They usually take it at a low level where the particle concentration and the concentration of heavy gases like NO2 are still high. Cabin air is thus collecting and storing emission peaks and air pollution in car cabins can therefore be extremely high - often ten times higher than even at roadside. Drivers commuting in big cities, taxi drivers, truckers and school buses might be exposed to this high pollution for several hours per working day, a group put at very high health risk.

Cabin air of today's vehicles usually passes a filter, but these filters are designed for visible road dust and pollen and according to the existing standards filtration of particles < 1 μm is very low. Lung penetration however, only starts < 0.5 μm. In the long run this could be changed by installing different filter systems, but what about the existing fleet? A filter system has been developed to reduce the concentration of ambient ultrafine particles in vehicle cabin air of in-use vehicles to very low levels, which is presented here.

The waste from end-of-life vehicles can be economically reused or forwarded for disposal. The UE 2000/53/EC directive imposes a recovery rate from end-of-life vehicles on the level of 95% of their weight and a recycling rate on the level of 85%. Changes in the material structure of vehicles observed in recent years indicate a gradual replacement of ferrous metals traditionally used in the automotive industry with plastics and composites, which mainly results from the need to reduce the vehicle weight, fuel consumption and CO₂ emission. Hence, the share of recyclable materials diminishes and the share of materials difficult (thus expensive) to recycle increases. The paper presents problems related to the recovery of materials from end-of-life vehicles. It presents the methods of waste management and identifies relations between the changes in the material structure and the recyclability of end-of-life vehicles. The paper also presents a comparison of the recovery rates possible to obtain using the best available technologies and the actual recovery rates from the recycling networks.

Ergonomics of transport means along with safety, availability, efficiency or eco-friendliness is one of the main assessment criteria for transport means functioning. Assessment of the considered transport systems operation depends on their operators' behaviour, functioning of vehicles and environmental factors. Having this in mind, it needs to be noted that the issue of transport systems ergonomics is, on the one hand closely related to the transport means, and on the other hand it directly affects peoples' actions and improves the possibilities to adapt to the environment, taking into consideration external factors. The aim of this study is to provide assessment and analysis of the influence of the operator's work place ergonomics of given transport means on the quality of transport services. The research object are delivery trucks, and motor cars, different in terms of the total capacity. In the first part of the study the problems connected with an operator's work place ergonomics is discussed and the concept of transport means ergonomics is defined. The role of ergonomics in a professional driver's work is specified. The factors and threats affecting safety of operators' behaviour are identified. A survey was developed and carried out among professional drivers to identify factors affecting the transport process as well as factors improving the driver's work comfort. On this basis, an analysis of the obtained results was made and negative ergonomic aspects involved in a vehicle driver's work place have been presented. The impact of selected elements of the driver's cabin equipment on safety and work comfort is evaluated. Problems ad their causes are identified. Solutions to these problems are proposed in order to improve ergonomics of the vehicle driver's work place, thus affecting the quality of a system operation according to the sociotechnical approach.

The economic system of a modern state requires efficient road transport, which plays an essential role in communication and freight transport. Such dynamic development of the automotive industry entails a number of negative effects, above all for the natural environment, causing pollution of air, soil and water as well as an increase in the amount of waste products generated during operation and disposal of motor vehicles. Mainly due to the threat to the natural environment, it is necessary to fully utilize waste products in the process of recycling and recovery. The aim of the article is to present the recycling effect on changes in the environmental impact during the production process of a vehicle.

Production and operation of vehicles currently has a significant impact on the environment. The choice of more environmentally friendly construction materials which a car is made from can significantly reduce its environmental impact. The main aim of this article was to compare the environmental impact assessment of changes in the design of passenger cars by using the life cycle assessment analysis (LCA). The paper presents a simplified LCA method of a car, which in specific cases can be used to analyse environmental impacts associated with the manufacturing process to assess the ecological performance of new passenger cars. In the adopted LCA simplification, the carbon dioxide equivalent emission CO2eq was used to assess the impact. The values of these variables were determined based on the mass of materials used to build the car. A practical example of using the simplified LCA method for a comparative assessment of the ecological efficiency of Volkswagen Group passenger cars manufactured over the last 30 years is presented.

The main objective of the management and control of the transportation system operation is to achieve the highest quality of its operation tasks execution. However, because of the system complexity the accurate determination of the system operation quality is very complicated. To optimize the efficiency of the activities performed to increase the operation quality, it was expressed in the quality states space. In the space the subspaces of the inadvisable, advisable, limited, acceptable and desired quality of operation were defined and the momentary quality of the system operation was expressed in form of the point. Taking into account the subjective character of the survey results and their linguistic inaccuracy the space was transformed into the fuzzy quality states space. Subsequently, the distance between the fuzzy set of the momentary system operation quality and the border of the desired quality subspace was defined. This way, for the quality states not belonging to the desired quality subspace, the minimal changes of the system features required to move this state to the subspace were calculated. The presented in the paper method allows optimizing the efficiency of the activities performed to increase the operation quality of the transportation system.

Experiment studies focus on increasing active safety (steerability and stability) of the combination of vehicles (car with a trailer). The aim of the conducted studies is increasing active safety in the motion of autonomous vehicles with trailer via creating algorithm of functioning of a system which facilitates forecasting of the possibility of dangerous behaviour occurrence for the vehicles combination during complex road manoeuvres at a high velocity. Within this scope the system will ensure collecting data from the environment, data selection (detecting the situation which requires reaction), as well as joining the information which require decision making about the further steps of the current manoeuver. As a result, corresponding control signals will be sent to the controllers.

The starting point in this work are synchronous measurements of physical quantities for the car and trailer. They enabled the analysis of trends in changes of relative position between the car and the centre-axle trailer during avoiding a suddenly appearing obstacle. The analysis results of these measurements enable pointing out the symptoms which will signal the possibility of danger in the movement of the combination (e.g. dropping a trailer). A special feature of the study is that the mass of a pulling car is comparable to the trailer's mass (1800 kg and 1840 kg).

The values of indexes which characterize the changes of quantities describing the movement of the combination of vehicles during avoiding a suddenly appearing obstacle have been measured. The subject of analysis was a difference in time of occurrence of characteristic indexes' values among the physical quantities describing the motion of the car and the vehicle. The results of the study confirmed that in the course of measured quantities such characteristic values can be detected, whose occurrence for the trailer is delayed by 0,2 to 0,5 s with respect to the car driving at a velocity of 60 km/h. This time span is sufficient for a corrective measure done by the controller of the autonomous car.

Front-to-side collisions of motor vehicles very often occur on Polish roads. Every fourth road accident may be defined as a collision of this kind between moving vehicles. The analysis of accident effects, including the accident reconstruction process, is usually based on results of measurements of post-accident vehicle deformation and on information about vehicle body stiffness. Unfortunately, the information about the characteristic curves that would represent the deformation of a car body side is hardly available.

The objective of this study is to present a method of determining the characteristics of deformation and side stiffness of a motor car body based on crash test results. This objective was pursued with using results of NHTSA crash tests and of crash tests carried out at PIMOT. The analysis covered herein has been based on crash tests representing front-to-side collisions of motor cars, motorcycle impact against a car side, and frontal impact of a car against a barrier. Based on a combined analysis of the course of such experiments, mathematical models have been built that describe the dynamics of the deformation process in the vehicle contact zone. The model calculation results obtained with using results of measurements carried out during the crash tests have been worked out with using the linear regression method.

Based on the experimental and analytic methods, curves were plotted that represented the impact force as a function of the deformation of individual car bodies and then the characteristics of car body side deformation were determined. The range of this deformation and the hazard arising from the side impact to vehicle occupants were also shown. A special aspect of this hazard has also been unveiled by the calculation results, according to which the side stiffness of a car body decreases with growing deformation depth. In the initial deformation phase, this stiffness is even by 35 % higher in comparison with that observed when the vehicle body side is deformed by more than 20 cm.

The aim of the present work is to determine the influence of TiB2 coating on the friction parameters in sliding pairs under lubricated friction conditions. The TiB2 coating deposited on modified surface layers of ring specimens made of 46Cr2 steel were matched under test conditions with counterparts made of CuPb30 bearing alloys. The tested sliding pairs were lubricated with 15W/40 mineral oil and 5W/40 synthetic engine oil. The lubrication of friction area with mineral oil causes the reduction of friction force and temperature in the friction area, whereas the lubrication with synthetic oil reduces the wear of the bearing and the changes in the geometrical structure of the cooperating friction pair elements. Lubrication of the friction area in the start-up phase of the friction pair by mineral oil causes faster stabilization of the friction conditions in the contact area than in case of lubrication of the friction pair by the synthetic oil.

Short-term car-sharing rentals are becoming increasingly popular in the urban transport systems world-wide Along with their development, the existing concepts are being also improved e.g. by means of introducing new fleets of vehicles, improving the task-oriented efficiency of vehicles, as well as by maintaining the economic capacity of the system.

According to the recent trend, many scientific studies are undertaken with an attempt to analyse various social, environmental or economic aspects related to the practical introduction of these systems. The niche area still to be exploited, however, is the research focusing directly on vehicles, i.e. a fleet of vehicles used in car-sharing systems, and on the issues related to its operation. The authors have focused basically on compiling a list of the most frequently used vehicles in car-sharing systems, defining vehicle classes and determining the type of their propulsion. Then they developed a list of maintenance issues, including daily service. Furthermore, they attempted to provide an inventory of main damages that may occur in car-sharing vehicles depending on the given vehicle mileage. The paper finally aims at raising awareness among the users of these systems regarding the activities related to the operation of a motor vehicle and its regular service.

Wheel alignment effects on vehicle's stability and steerability, so it has a significant influence on, so called, active safety of a car. That's why it is important to regularly check and properly adjust the wheel geometry. The measurements should be performed according to specific requirements. The influence of measurements conditions on results of a wheel geometry check is analysed in this paper. The results of measurements of wheel alignment of three cars with different suspension types are presented and the influence of measurements condition on the obtained results is discussed.

The article presents a critical analysis of available technologies for the production of automotive components from polymer composites. The advantages and disadvantages of currently used manufacturing technologies are presented. A new technology for the production of vehicle components is proposed by pressing a newly developed powdered epoxy resin. This generates new technological possibilities in the production of vehicle parts and subassemblies.

Proper public transport vehicles utilization is a key factor in effective and efficient communication in every city. Number of vehicles in use at any point in time is crucial piece of information to both transportation organizers and carriers, since it allows for control and reaction in case of an emergency. This article presents an analysis of public transport vehicles utilization in regard to day of the week and carriers responsible for public transport in Lublin.