Instytut Transportu Samochodowego

With the growing deployment of electric buses (e-buses), accurate energy use modelling has become essential for fleet optimisation and operational planning. Using the SORT methodology, this study analyses instantaneous energy consumption and recuperation (IECR). Three vehicle configurations were tested (one battery with pantograph, four batteries, and eight batteries), each with ten repeatable runs. Four approaches were compared: a baseline linear regression, an extended linear model (ELM) due to the state, a feed-forward neural network, and a recurrent neural network (RNN). The extended linear model achieved a determination coefficient of R2 = 0.9124 (residual standard deviation 4.26) compared with R2 = 0.7859 for the baseline, while the determination coefficient for the RNN is 0.9343, and the RNN provided the highest accuracy on the test set (the correlation coefficient between real and predicted values is 0.9666). The results confirm the dominant influence of speed and acceleration on IECR and show that battery configuration mainly affects consumption during acceleration. Literature-consistent findings indicate that regenerative systems can recover 25–51% of braking energy, with advanced control methods further improving recovery. Despite non-normality and temporal dependence of residuals, the state-aware linear model remains interpretable and competitive, whereas recurrent networks offer superior fidelity. These results support real-time energy management, charging optimisation, and reliable range prediction for electric buses in urban public transport.

This paper presents an analysis of the impact of conducted and radiated electromagnetic interference affecting the electrical circuits of electronic security systems (ESS) operating over wide areas. The Earth’s electromagnetic environment is heavily distorted by intended and unintended (stationary or non-stationary) sources of radiation. The occurrence of electromagnetic interference in a given environment where an ESS is in use is the cause of damage or malfunction of the entire system or its individual components, e.g., detectors, modules, control panels, etc. In this article, the authors conducted an assessment of the electromagnetic environment where ESS are operated and conducted studies of selected sources of interference. For selected ESS structures, they developed models of the impact of conducted and radiated interference on the process of using these systems in a given environment. For selected technical structures of ESS, the authors of this article developed models of the operation process. They also carried out a computer simulation to determine the impact of natural and artificial electromagnetic interference occurring on the process of using these systems in a given environment over a wide area. The considerations carried out in this article are summarized in the conclusions chapter about the process of using ESS in a distorted electromagnetic environment.

The article addresses the usage patterns of plug-in hybrid vehicles (PHEVs) under Polish conditions. The conventional approach to operating such vehicles assumes that they are used with a fully charged battery at the start. However, the economic circumstances of Polish users often do not allow for daily charging of vehicles from the domestic power grid. As a result, these vehicles are used not only in a mode powered solely by the internal combustion engine but also in a mode where the internal combustion engine is primarily utilized to charge the battery. An analysis was conducted on various ways of operating plug-in vehicles, evaluating not only harmful emissions but also fuel consumption (for battery states of charge: SOC = 100%, SOC = 50%, SOC = 0%, and SOC = 0 → 100%—forced charging mode). The study focused on the most characteristic vehicle segment in Poland, SUVs, and employed a methodology for determining exhaust emissions under real-world driving conditions. Results indicate that forced charging of such a vehicle’s battery leads to over a 25-fold increase in carbon dioxide emissions (fuel consumption) in urban areas compared to operating the vehicle with a fully charged battery (CO—25× increase, NOx—12× increase, PN—11× increase). Operating a plug-in SUV without charging it from the power grid results in a 13-fold increase in fuel consumption compared to using the vehicle with a fully charged battery (CO—10× increase, NOx—6× increase, PN—4× increase). The emission results were used to evaluate Poland’s charging infrastructure in the context of PHEV usage. The current state of the infrastructure and its development plans for 2030 and 2040 were analyzed. It was found that significant reductions in fuel consumption (by approximately 30%) and CO2 emissions are achievable by 2040. Emissions of CO, NOx, and PN are expected to decrease by about 10%, primarily due to the internal combustion engine operating at high load conditions in non-urban or highway scenarios.

BackgroundIn 2022 in Poland pedestrians constituted 24.3% of all road fatalities and 22.2% of seriously injured. The number of killed pedestrians decreased in comparison with 2021 by 12.7% and data for 2013–2022 show drop in the number of fatalities by almost 60% and seriously injured by 46%. Among road accidents causes not giving priority to pedestrians, which resulted in 13.4% road accidents, 8.4% fatalities and 13.7% seriously injured, was listed on 3rd position.ObjectiveTo protect the pedestrians a series of improvements has been introduced in Poland, including legal changes and infrastructural measures. Their aim is to improve pedestrians’ safety further as it remains one of the major road safety issues.Policy AnalysisOne of the pillars of National Road Safety Programme 2021–2030 with objectives to reduce number of fatalities and seriously injured by 50% is dedicated to safe road user. Within Safe Road Infrastructure Programme 2021–2024, actions are aimed at increasing the protection of road users by creating safe road infrastructure - and, as a result, reducing the number of accidents and their victims. In recent years road safety audits of pedestrians crossings were performed resulting in installation of lightning at selected crossings. In 2021 legal regulations were introduced that gave priority to pedestrians approaching the zebra crossing and banned pedestrians from using mobiles while crossing roads. In 2022 new list of fines for traffic violations was published, including not giving priority to pedestrians by drivers. Changes in demerit points system aimed at protecting pedestrians more. The National Road Safety Council launched campaigns concerning pedestrians and senior safety.Policy ImplicationsThe mentioned solutions lead to improvement of pedestrians’ safety in Poland and receiving in 2023 the European Transport Safety Council PIN award for best performance in road safety for 2022. However, there is still lots to be done as especially vulnerable road users remain at risk on polish roads.ConclusionsDeveloping and implementing regulations and standards to protect vulnerable road users is crucial and financial outlays are expected, therefore decisions need to be adapted to changing conditions and partial audits are important to monitor the advancements.

BackgroundIn the EU, approximately 15% of the population are disabled people. Using the biological disability criterion, this group in Poland can be counted from 5.3 to even 9 mln. The protection of vulnerable road users (including people with mobility issues) is one of the pillars of worldwide road safety improvements. The activities undertaken for this purpose are diverse and multi-level.ObjectiveIn 2022, a team including the authors started the study to support the mobility and safety of pedestrians with lower limb disabilities. The aim of the study is to develop and implement a multifunctional attachment for orthopedic equipment as an element improving comfort and safety in various weather conditions. An orthopedic crutch attachment is based mainly on an innovative idea regarding shape and materials used. The appropriate attachment enhances the user’s sense of stability and the ability to firmly lean on it. The aim of the study was to first learn about the expectations of users regarding the attachment’s features.MethodsThe study included qualitative research (Focus Group Interviews,FGI) with the participation of PRM – pedestrians using similar equipment. The purpose of FGI was to learn about users’ opinions and evaluate the presented attachment prototype. Participants defined most important features of attachment and were asked to explain the concepts of road traffic safety, mobility, accessibility and to discuss their experiences related to safe traveling and use of movement facilitating solutions.ResultsThe participants positively assessed proposed solution and expressed willingness to use it. FGI study showed low level of users’ knowledge regarding variants and technical possibilities of orthopedic equipment, its selection, purchase places, exchange conditions, existence of advisory offices/persons, and awareness about the importance of this item for safe and comfortable movement. The need for more systemic support for PRM was indicated, e.g. by establishing special information and advisory points.ConclusionsAlthough there are many supporting devices, research has shown a significant communication gap among users, orthopedic equipment manufacturers, health services and decision-makers. Filling this gap will enable more conscious selection of pedestrian devices. Such health prevention will also affect the safety of this group of road users.

Vulnerable road users are the largest group of road accident victims in the world. At the same time, it should be noted that most road accidents are caused by the motor vehicle driver. An opportunity to increase the level of road safety is emergency braking systems installed in vehicles. Their task is to detect the risk of a collision with another object, issue a warning to the driver and, in the absence of reaction, perform emergency braking. The publication presents the results of research conducted by the Motor Transport Institute as part of the PEDICRASH project. As part of the work, a series of tests of the autonomous emergency braking system were carried out to check unusual but probable cases of events in which it should work. The tests were carried out in a closed area using a few selected models of popular passenger car brands. An additional data acquisition system and dummies imitating vulnerable road users: pedestrians and cyclists were used. The constructions represent the silhouette of an adult person and meet the requirements of the Euro NCAP AEB Protocol. The time of the collision at the time of issuing a warning to the driver was analyzed. Assuming that the vehicle was moving uniformly, the distance from the obstacle was calculated at the time of issuing the warning and after the driver's reaction time (0.7 s and 1 s were assumed) from this signal. The deceleration necessary to brake the vehicle was calculated and it was determined whether the driver would have a chance to brake the vehicle before a pedestrian or a cyclist in a given situation. For cases in which the driver would not be able to brake in time, the speed of the vehicle with which it would hit the vulnerable road users was calculated. Possible injuries and accident costs were then estimated.

The second decade of the 21st century saw the introduction of vehicles equipped with various driver assistance systems. However, the producers' plans go much further. In January 2023, Mercedes-Benz's DRIVE PILOT system was approved for use on public roads in Nevada (United States) as the first and so far only SAE Level 3 series-production solution. Despite increasing automation, the human factor remains important for the safety and efficiency of road transport. In the coming years, and possibly decades, this will mainly be due to the co-existence of vehicles with varying degrees of automation and necessary driver-vehicle interactions in cases where an automated driving system crosses the boundaries of the operational design domain. The latest research reveals the limitations of driving assistance systems, pointing not only to the need for changes in the technological domain but also to the need to pay more attention to the psychological aspects of using assistance systems in cognitive and behavioral areas. Therefore, an additional element of automation implementation should be considered, which is driver training focused on modern technological solutions. Properly arranged and conducted training can be treated as an additional factor facilitating the implementation of automated mobility. The article describes the methods of assessing the effectiveness of training in terms of familiarizing drivers with the functions that automate driving. The authors present the results of tests carried out on a driving simulator with an implemented Level 4 system (according to SAE classification). Three forms of knowledge transfer were analyzed: practical training, e-learning, and training with a short user manual. The results were compared in terms of driver-vehicle interaction effectiveness (e.g., system activation), ensuring that the driver is sufficiently reactive in dangerous situations and understands the limitations of the system. The research was conducted on a group of 81 drivers aged 18–65. Driver training was one of the main pillars of the Trustonomy project, which received funding from the EU research and innovation program Horizon 2020 under grant agreement No. 815003.

The paper concerns the study of changes in responses of spring for drum brake systems, due to fatigue cycles conducted at operational regimes of vehicles with respect to the number of kilometers. Three types of springs from two manufacturers were examined i.e. double cylindrical, single cylindrical, and conical helical. The springs were subjected to a durability test up to 1×10 6 loading cycles, covering 300-500 thousand kilometers traveled. Tensile test was used for collecting differences between results for the tested object in the as-receive state and after fatigue. Values of the Pearson correlation coefficient were used to indicate differences between tested objects before and after loading cycles. They show that the obtained results expressed a very strong correlation, which means that the elastic response of the springs during operation over a distance of 300-500 thousand kilometers did not change significantly. Taking into account the recommendations of brake system manufacturers regarding the replacement of brake drums after 150,000 and 50,000 kilometers, respectively, it can be concluded that brake springs are the most durable and reliable element of such a brake system.

The Covid-19 pandemic unexpectedly shook the entire global economy, causing it to destabilize over a long period of time. One of the sectors that was particularly hit hard was air traffic, and the changes that have taken place in it have been unmatched by any other crisis in history. The purpose of this article was to identify the time series describing the number of airline flights in Poland in the context of the Covid-19 pandemic. The article first presents selected statistics and indicators showing the situation of the global and domestic aviation market during the pandemic. Then, based on the data on the number of flights in Poland, the identification of the time series describing the number of flights by airlines was made. The discrete wavelet transformation (DWT) was used to determine the trend, while for periodicity verification, first statistical tests (Kruskal-Wallis test and Friedman test) and then spectral analysis were used. The confirmation of the existence of weekly seasonality allowed for the identification of the studied series as the sum of the previously determined trend and the seasonal component, as the mean value from the observations on a given day of the week. The proposed model was compared with the 7-order moving average model, as one of the most popular in the literature. As the obtained results showed, the model developed by the authors was better at identifying the studied series than the moving average. The errors were significantly lower, which made the presented solution more effective. This confirmed the validity of using wavelet analysis in the case of irregular behaviour of time series, and also showed that both spectral analysis and statistical tests (Kruskal-Walis and Fridman) proved successful in identifying the sea-sonal factor in the time series. The method used allowed for a satisfactory identification of the model for empirical data, however, it should be emphasized that the aviation services market is influenced by many variables and the fore-casts and scenarios created should be updated and modified on an ongoing basis.