Odbor znalectví ve strojírenství, analýza dopravních nehod a oceňování motorových vozidel

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    What should I use to calculate vehicle EES?
    (PUBLIC LIBRARY SCIENCE, 2024-02-08) Moravcová, Pavlína; Bucsuházy, Kateřina; Zůvala, Robert; Semela, Marek; Bradáč, Albert
    Comprehensive crash analysis includes calculating impact speed, which requires the determination of kinetic energy expended on the deformation of the vehicle's structural elements at the point of contact during a collision. The accuracy of the input data affects the resulting analysis of the crash. Therefore, this article aims to analyse selected factors influencing the determination of Energy Equivalent Speed (EES) determination using the CRASH3 algorithm: the extent of damage using defined measurement points, deformation width, and also limit speed b0. The variables were varied depending on selected factors such as the extent of damage, the type of collision (overlap), and also vehicle type (vehicle category classification). The presented study concluded that using 2 equally spaced measurement points to define the deformation profile should not be recommended in forensic practice when using CRASH3 algorithm. Using 7 measurement points seems more appropriate in case of equal spacing, even though the differences in calculated EES are not high when using 5 or 6 measurement points, especially with respect to the inaccuracy/technically acceptable tolerance of the EES value determination. The resulting EES is significantly influenced by variation of the deformation width. The used b0 range had a significant effect on the resulting EES value only in the case of SUVs. These vehicles show higher stiffness, which supposes the use of lower b0 values should not be recommended.
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    Multimodal Features for Detection of Driver Stress and Fatigue: Review
    (IEEE, 2021-06-01) Němcová, Andrea; Svozilová, Veronika; Bucsuházy, Kateřina; Smíšek, Radovan; Mézl, Martin; Hesko, Branislav; Belák, Michal; Bilík, Martin; Maxera, Pavel; Seitl, Martin; Dominik, Tomáš; Semela, Marek; Šucha, Matúš; Kolář, Radim
    Driver fatigue and stress significantly contribute to higher number of car accidents worldwide. Although, different detection approaches have been already commercialized and used by car producers (and third party companies), research activities in this field are still needed in order to increase the reliability of these alert systems. Also, in the context of automated driving, the driver mental state assessment will be an important part of cars in future. This paper presents state-of-the-art review of different approaches for driver fatigue and stress detection and evaluation. We describe in details various signals (biological, car and video) and derived features used for these tasks and we discuss their relevance and advantages. In order to make this review complete, we also describe different datasets, acquisition systems and experiment scenarios.
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    How to Assess the Dangerousness of Driving Situations at Pedestrian Crossings
    (EVU, 2023-10-05) Maxera, Pavel; Kledus, Robert; Semela, Marek; Bilík, Martin; Bradáč, Albert; Rak, Martin
    The paper analyzes drivers' behavior when solving complex driving situations at pedestrian crossing locations. The findings of the research are based on a detailed analysis of 129 driving tests carried out in real road traffic. The results of the evaluation clarify important characteristics of drivers' behavior at pedestrian crossing locations. Of particular importance are the findings on when pedestrians become an important visual stimulus for drivers, how the driver's behavior affects the complexity of the driving situation, and the overall design of the location where pedestrians cross. From these findings, appropriate criteria for assessing the hazardousness of such driving situations are derived, and limits are found. These limits allow, based on relatively easy-to-detect quantitative data, to determine the dangerousness of a particular driving situation in real road traffic. According to the authors, the findings are particularly useful in assessing the ability of road users to prevent an accident from occurring. Using the results allows experts to assess better the causal links associated with traffic accidents, thus facilitating a further legal assessment.
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    Analysis of selected off-road glances during driving in real road traffic
    (Elsevier, 2020-03-20) Bucsuházy, Kateřina; Semela, Marek; Belák, Michal; Maxera, Pavel; Bilík, Martin; Rábek, Vlastimil; Zůvala, Robert
    The aim of this ongoing research has been the analysis of driver visual behavior in real road traffic. The paper deals with analysis of duration of selected off-road glances. The total gaze duration depending on mirror type has been analysed and also the total gaze duration depending on the navigation task type. For the purpose of this study eye-tracking technology has been used. Eye-tracking method is used to measure motion of an eye relatively to a head. The total gaze duration depending on mirror type has been analysed and also the total gaze duration depending on the navigation task type. The average value of total off-road glances regarding to the checking situation in vehicle mirrors is 1,2 s. The glance frequency distribution shows that the drivers used the right rear-view mirror minorly. As evidenced by the obtained results, the total off-road glance time on the navigation system is dependent on the type of the navigation task. The average value of total off-road glances regarding to the use of the navigation without audio information is 0,9 s, with audio and video navigation system is the average off-road glance time 0,6 s.
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    Let It Crash! Energy Equivalent Speed Determination
    (SciTePress, 2021-04-30) Moravcová, Pavlína; Bucsuházy, Kateřina; Bilík, Martin; Belák, Michal; Bradáč, Albert
    Crash analysis including calculation of the impact speed and related determination of deformation energy is one of the main assumptions for the clarification of mostly negligent crimes. In this article were introduced results of two crash tests representing the comparison of the stiffness and technological obsolescence and their influence on the resulted vehicle deformation. Different extent of vehicle deformation was used to demonstrate the limits of selected methods for Energy Equivalent Speed determination as a value which expresses the kinetic energy dissipated by the vehicle during the contact phase.