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

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.

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.

This paper deals with Dynamic analysis of Scissor Lifts during the Load Lifting to determine their dynamic behavior, find the nature of oscillations, and the regulation of lifting to minimize these oscillations and optimize the work process. During the motion processes, the lift and its main parts undergo heavy forces, moments, and oscillations. The method of research is acquiring results through design, modeling, and simulations, comparing them with analytic calculations, and looking for the optimal motion regulation of the Load Lifting. The analysis will be acquired when the Scissor lift is carrying maximum Load. The study will be concentrated in the finding the nature of dynamic forces and stresses that acts on the main parts of the lift and the extent and the form of oscillations. Results will be shown in the form of diagrams and contour views as the solution results of the tested system. Modeling and simulations will be carried using software SimWise 4D, based on the type of the Scissor Lift taken from Standard Manufacturer. Conclusions of these analyses are useful for design considerations, dynamic behavior, and safety of these types of lifts.

This paper deals with dynamic analysis of bridge crane with one main girder during telpher motion in order to determine dynamic behavior and oscillations while carrying full load. During the telpher motion the main girders and side girders are heavy loaded parts while they undergo forces, moments and oscillations from lifting mechanism that carries workload. The method of analysis is the comparison of results gained through modeling and simulation and experimental measurements. The analysis will be concentrated in finding the nature of dynamic forces, moments and stresses that acts on main crane’s parts and finding the extent and form of oscillations that can cause damage and failures. Also the interest is to study the effects of load swinging in crane’s stability. Results will be shown in the form of diagrams as the solution results of the tested system. Crane is modeled from standard manufacturer, as a special type of Bridge Crane with one main girder and telpher. Conclusions of these analyses are useful for design considerations, dynamic behavior and safety.