International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The activity of snow removal on public roads is of particular importance for ensuring road transport in winter and implicitly for maintaining a stable, predictable and efficient economic and social climate. The organization of road snow removal is usually done by the local public authorities, through the public road administrator, varying depending on the geographical and climatic location of the road site. In Romania, the snow removal activity is regulated by the “Regulation on preventing and combating snow on public roads”, indicative AND 525-2013, developed by the National Company of National Highways and National Roads in Romania. The snow removal activity is usually performed on the basis of a service contract and is temporary, depending on the evolution of meteorological phenomena and climatic zones.
The actions to prevent and combat the consequences of dangerous meteorological phenomena are carried out according to their intensity on the following phases, as follows: prevention of icing formation and its neutralization, spreading of anti-skid material and snow removal. The preventive spreading of the anti-skid material is recommended to be done first on the entry / exit arteries in / from the localities. The activity of mechanical cleaning of public roads (streets, bridges, alleys, roundabouts) of snow with blade machines is performed when the snow layer exceeds the thickness of 5 cm. The activity is carried out by successive passages, starting from the axis of the road to the curb, until the complete removal of the snow layer.

Modern vehicle braking systems mainly are based on deceleration of vehicle and tire slip control. Trends in improving vehicle braking performance give rise to a large variety of braking systems and control strategies. An anti -lock braking system is an electronic braking process control system, which greatly increases the ability of the driver and vehicle to avoid road accidents even during difficult braking conditions or circumstances. The load (number of passengers in the vehicle) which is transmitted to the road surface through the vehicle tires is an issue which directly affects the braking efficiency of the vehicle during stopping. The braking efficiency also depends on
the material of the road surface, climatic condition, road condition, vehicle speeds and tire condition.
The purpose of this paper is investigation the impact of the number of passengers in the vehicle during the braking process, respectively to determine the performance of the braking of vehicles equipped with modern mechatronic braking systems such as: Antilock Braking System, Electronic Braking System, Emergency Brake System and Electronic Brake-force Distribution System.
The braking performance of the vehicle was determined experimentally through the XL Meter device which was fixed on the windshield of the VW Polo vehicle. The tests were performed on asphalt roads for different speeds of 40, 60 and 80 km/h. The determination of the center of gravity of the vehicle and the reaction forces in the front and rear axles was performed through the devices in the Motor Vehicle Laboratory of the Faculty of Mechanical Engineering and the developed mathematical model for calculating static and dynamic reactions forces for the respective axes. The obtained results will help the traffic experts in the analysis of road accidents.

Patents for inventions in the field of measures for preventing and combating the freeze-thaw phenomenon of roads address a topic related to the evolution of technology. Of particular importance is the stabilization of the substrate of the road transport route. An invention (J. Hornegger, N. Zanfir, M. Alupoaie, 2012) relates to a mixture used for the substrate of access roads and / or platforms. This invention relates to another invention (Y. Kadono, T. Nakazato, E. Miura, T. Kitamura, 1975) about a paved roadbed composed of a lower roadbed layer, an intermediate layer made of sulfur, an upper roadbed layer and a surface top layer. Another invention (D. Lee, K. Hong-joo, 2016) relates to a repairing and reinforcing ultrarapid hardening mortar composition, and to a method for repairing and reinforcing a road surface. Another invention (M. Radu, F. Radu, L. V. Pasăre, I. A. Buzuriu, P. Pârvu, C. G. Mudreţchi, C. Răcănel, A. Burlacu, V. Tiron, 2018) relates to a process for preparing ecological composite asphaltic mixtures to be used as road structures.

In the Republic of Kosovo, the unemployment rate has an increasing trend, the average monthly income is still low, which makes it impossible to buy a new vehicle, so they are forced to buy vehicles imported from European countries, which have a h igh rate of amortization.
Citizens who own used vehicles are obliged to perform services that cost less by avoiding quality equipment and replacing them with non-know manufactures for spare parts which cost cheaper compared to manufacturers of well-known and guaranteed brands. The use of such spare parts is directly affecting the increase in the number of accidents in the territory of the Republic of Kosovo. In this paper is study the efficiency of brake pads from different manufacturers – brands in the term of the braking system in passenger vehicles such as: braking time, maximum deceleration and braking distance. The tests were done with used vehicles equipped with the ABS system, on roads with dry asphalt. The used tires are from radial construction with summer characteristics. Depending on the treated methodology, the adequate equipment such as Xl meter, video cameras and meter are used. The obtained results through the decelerometer device (Xl meter) for deceleration of the vehicle and other indicators of the efficiency of the braking system has done with the case of emergency braking. Prior to each test, the predicted used vehicle has performed also technical inspection of the vehicle braking system in the Licensed Centers for technical inspection of the vehicle.

In the paper, energy recuperation and management in automotive suspension systems with linear electric motors controlled using a proposed H∞ controller to obtain a variable mechanical force for a car damper is presented. Vehicle suspensions in which forces are generated in response to feedback signals by active elements obviously offer increased design flexibility compared to the conventional suspensions using passive elements such as springs and dampers. The main advantage of the proposed solution using a linear AC motor is the possibility to generate desired forces acting between the unsprung and sprung masses of the car, providing good insulation of the car sprung mass from the road surface disturbances. In addition, under certain circumstances using linear motors as actuators enables to transform mechanical energy of the vertical car vibrations to electrical energy, accumulate it, and use it when needed. Energy flow control (management) enables to reduce or even eliminate the demands concerning the external power source.