Effect of vibrations on the behaviour of a vehicle driver

The article provides a discussion on the results of studies conducted in a road network of both Silesian and Lesser Poland Voivodeship. The goal of the research in question was to establish relationships between vibrations of an automotive vehicle and its driver’s behaviour. For that purpose, the test vehicle was equipped with a linear acceleration recording device and a GPS signal receiver

Simulation studies of a shock absorber model proposed under conditions of different kinematic input functions

The paper presents the results of simulation research of visco-elastic model of shock-absorber. Tested shock absorber has been in the suspension system. The aim of research was determine values of force of damping for different kinematic input functions. The results are presented in graphical form that allows for their analysis

Simulation of a visco-elastic damper based on the model of the vehicle shock absorber

This paper presents results of simulation of visco-elastic dampers based on the model of the vehicle shock absorber. The aim of this research is to determine the parameters of dynamic models of special dampers applicable in advanced vehicle suspension systems. One of the key issues of modeling is to determine the acceptable degree of the simplification. Model reduction is based on the determination of the damping coefficient suitable for testing vibration control systems. The diagnostic model of the shock absorber takes into account features such as nonlinearity and asymmetry of damping characteristics. It is also important to take into account the apparent elasticity of the hydraulic damper. Damping and stiffness characteristics of automotive shock absorbers are identified by the proposed algorithm. The obtained results proove that the resulting damper stiffness is an important factor which cannot be neglected at higher frequencies of cyclic load

Mobile analysis of railway traffic safety

The paper presents a universal and extremely simple method for studying railway traffic safety, which enables the measurement of safety-related aspects to be conducted with reference to both infrastructure and rolling stock at the same time. The method proposed in the article is an attempt to face up to the challenge of the aforementioned constraint, enabling measurements of characteristics of the railway line infrastructure and of the rolling stock by means of common accelerometers installed in mobile phones. Result obtained illustrates accelerations recorded in three axes. Studying average characteristics for the same train set, one can reveal anomalies related to the track or the rolling stock condition

Measurement and mathematical function of the actuation force of the rail switch drive

The paper presents results of measuring the force of the adjustment of the rail switch drive by spindle. The actuation force is the maximum force with which setting valve of the drive done to change position of the point. The simulation research requires proper mathematical model of the actuation force of the rail switch drive. Thus, the verification of such model requires real data measured on real object. The paper presents results of measurement and method of real data analysis

Identification of the parameters of visco-elastic model of the hydraulic vibration absorber

The paper presents the results of visco-elastic dampers. Their aim was to determine the parameters of dynamic models. A key issue in modeling is to determine the acceptable degree of simplification. According to the authors diagnostic models must take into account characteristics such as nonlinearity and asymmetry damping characteristics. Also, it is important to take into account the apparent elasticity of the hydraulic damper. Sample parameters of dynamic models of automotive shock absorbers are presented in graphical form

Research on vibroacoustic phenomena of tram vehicles for the changeable dynamics conditions

The article addresses the methodology and the results of studies of vibroacoustic phenomena generated by tram vehicles. While a tram was running at various speeds, both the noise level and surface vibrations were recorded simultaneously. These quantities determine the overall impact of tram cars on their environment. The research assumptions made enable assessment of accretion of these effects in the function of running speed, which may prove particularly for the sake recommendations as to the permissible speed of trams in urban conditions

Application of safety and communication modules as an integrated intelligent system in rail vehicles

This paper presents of Integrated System of Supporting Information Management in Passenger Traffic (the polish acronym of the system is ZSIKRP Demonstrator+). Currently on the polish and, as far as we know, international market such integrated solution is not developed and proposed. In this concept the final customer, e.g. the manufacturer or carrier company, will install one complete solution instead of multiple different installations that are usually difficult or even impossible to integrate. In our opinion the integration leads to increase in safety level of public transport and to improvement the quality of services offered. The novelty of the system is to provide collision, threats detection and fire alarm system integrated into a single coherent solution. In the collision detection module there is a need to apply devices that are resistant to physical disturbances, such as vibrations or strong fluctuations in temperature. One can either use the sensors made in MEMS technology (Micro-called Electro-Mechanical-Systems or micro-electromechanical) or other solutions made in the form of a monolithic integrated system in a standardized enclosure adopted to SMD mounting standard. A practical example of such a sensor is a new digital accelerometers that have a large measurement range (from ±120 g to ±480 g), and the choice of communication. The implementation of the collision detection module based on a monolithic integrated systems in MEMS technology

Determination of the effect of tire stiffness on wheel accelerations by the forced vibration test method

The paper presents results of a vibroacoustic signal analysis of the unsprung mass in a car actuated by harmonic kinematic vibrations. A passenger car with a hydropneumatic suspension system and standard tires was examined. Different tire pressures were used during the experiments. The authors applied the short time Fourier transform method with superposition of the Hanning windows combined with the zero complement method. With reference to the STFT spectrum, values of the unsprung mass resonance frequency were identified. The results of the experiments described in the publication are particularly useful for the personnel of vehicle service stations, especially that they relate to the effect of tire pressure changes occurring in a vehicle with a hydropneumatic suspension system on the vibration test results

Passenger safety and information module in intelligent integrated traffic management system

The article presents selected components of the prototype of the integrated system of supporting information management in passenger traffic (the polish acronym of the system is ZSIKRP Demonstrator+). The system is equipped with significantly expanded range of offered functionality, which corresponds to the current demands of the market. Additionally, it has features distinguishing it from other products available on the market. Prototypes of the system installed in two versions: for electric (EZT) vehicle (EN57 1756 – type in Mazovia Railways) and diesel (SZT) (SA 132 006 – type in regional public transport) vehicle. ZSIKRP system also focuses on ensuring the safety of travelers in both types of vehicles: EN57 1756 (EZT) and SA 132 006 (SZT). It is done by installation of the collision and threats detection module, thus it will be possible to transfer information about possible emergency situation to supervision center and immediately to crisis management center. Particular attention has been given to test collision and threats detection module and stabilization of measurements