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The subject of the considerations presented in this article are experimental braking performance tests carried out on dry surfaces for three selected vehicle types: passenger vehicle, delivery truck and touristic bus. The paper describes factors affecting braking performance. The tests were repeatedly carried out on dry asphalt pavement using specialized testing equipment. The deceleration was determined as a function of time and the maximum deceleration values were determined. Statistical analysis of the obtained results was performed, mean values and values of standard deviation were determined. Based on the conducted experiments, it can be stated that the maximum deceleration braking on asphalt surface depends on the type of vehicle. For a passenger vehicle it can reach even 12m/s2.

The article presents a review of the main indicators of driving quality and vehicle safety. These indicators allow to characterize the behavior and skills of a given driver and to compare them with each other. They are also the basic measurable source, which is very important in the aspect of research. The research itself, through the use of indicators, makes it possible to assess the quality of driving and the safety performance of the activity. The literature contains a number of definitions relating to the indicators presented, which differ from one another. This makes the definition adopted and therefore the methodology of measurement is often different and comparing test results makes no sense. Therefore, the article contains the most popular and accurate terms and definitions of these indicators, which have also been graphically interpreted as far as possible.

The study analyzes the relation between vehicle traffic parameters, i.e. volume, speed, noise and road accidents within the time period of one year. The data regarding the number of accidents was obtained from the Polish Accident and Collision Records System (Polish abbreviation - SEWIK). Traffic flow, vehicle speed and urban traffic noise were recorded by two traffic and noise monitoring stations at Krakowska and Lodzka streets in Kielce in 2013. The road noise was calculated according to the Cnossos-EU method and compared with measured values. Relation between the median of the number of traffic accidents, traffic volume, vehicle speed and noise in subsequent hours of the day was analyzed. High values of the correlation coefficient calculated for the relationship between the number of road accidents and traffic volume, speed and noise were found. In the case of Krakowska street (Road No 762), the values of this coefficient were, respectively: 0.88, -0.83 and 0.74. For Lodzka street (Road No 74), the values of the correlation coefficient between the tested parameters were 0.89, -0.82 and 0.85. The study showed that the largest number of road accidents occurs during the morning and afternoon rush hours. At these times of the day the noise is also the highest. The possibility of using the median of the road noise and traffic volume as a traffic accidents descriptor was examined.

This article discusses a study of driver behavior in a simulated pre-crash situation. The tests were performed on a track and aimed at determining the time of the driver response to a pedestrian intruding from the left or the right. A specially developed test stand with pedestrian mockups was used. The values of the brake reaction time and the steering reaction time obtained for 30 drivers were considered in relation to the time to collision (TTC). The analysis involved determining the linear regression equations for the mean, the standard deviation and the 0.1, 0.25, 0.75 and 0.9 quantiles, which are typical measures used by forensic automotive engineering specialists. The article also provides the ranges obtained for the brake reaction times and the steering reaction times. The experimental results show that the driver response time can be analyzed as a linear function of the TTC. The means of the driver response time determined for the two variants of the scenario tested indicate that the time of response to a pedestrian entering the path of the subject vehicle from the left is longer than that obtained when a pedestrian intrudes from the right.

The paper presents a test stand and a special control system with data acquisition for the experimental analysis of physical quantities during a vehicle crash test. The crash tests are carried out at low speed of a trolley with a dummy with various seat belts (from 2-point seat belts to multi-point seat belts). Particular elements of the test stand and the control system are characterized and the measuring apparatus is presented. The measuring apparatus allows to register and specify displacements of the parts of the dummy's body, the values of forces in the safety belts and the values of deceleration on individual parts of the dummy body. During the experimental investigations, the waveforms of forces in the 3-point hip and shoulder parts of the belt in the range of crash speed 15.54–17.48 km/h were determined. Using the approximation method, the empirical relationships between the value of crash speed and the values of forces in the seat belts were determined. The results showed that despite the low speeds, the values of forces between the dummy and the 3-point belts reach significant values of up to 5 kN with the dynamic increase rate of 30 kN/s.

This paper is devoted to modern problems of reinforcement materials used in car bumpers manufacturing and as well as safety issues. Paper discusses methods and provisions for car bumper reinforcement material., As result the fail-safe energy absorbing construction is presented and tested, made from laminates A, B and C with sandwich filling of the method vacuum bagging, which confirmed the possibility of absorbing energy (i. e. work) in the entire range from 3.858–6.680J (for a stationary barrier with an impact velocity of V = 10–15 km/h — formula 1). It was found that the destruction of sandwich laminates with sandwich fillers took place by cutting the interface and the resin layer between the carbon cloth layer and the glass matting layer. The highest impact value was determined for laminate A at the level of 133.75 J (with Soric XF™filling), which was characterized by inter-layer cracking with plastic deformation of the core. Lower by about 65 and about 36% of the average impact strength for laminate C and B respectively compared to the average impact strength of laminate A, the of observed as a result of defects in the structure (i.e. plastic core deformation and one-sided delamination of aluminum and polypropylene respectively — PP from the components of the composites). In future using sandwich structured composites materials is very important from cost profitability from point through, testing and manufacturing, as well as composites repairs.

Some aspects of marine electric power plants load registration and identification have been presented. Methods of operating data collecting about marine electric power plant loads have been shown based on an example of three vessels - a chemical tanker, a container ship and a tanker. Power plants of these vessels have been described. Examples of collected operating data were presented. Range of marine electric power plant load identification research has been characterized, which presented in the paper results are a part of.