Tourism is directly related to passenger transport. For the improvement of quality of transport, thus-tourist services and quality of human life, the road vehicles are constantly developing. The moving speeds are rising and therefore-the accelerations acting on the passengers rise too. As a result-the comfort level drops. During cornering with high speeds lateral accelerations, which are a powerful irritant, causing discomfort, nausea and motion sickness called kinetosis, are generated. Systems for passenger cars tilting, which reduce lateral acceleration, are being used for a long time in railway transport. In automobiles such systems are harder to engineer and that is why they are still in experimental phase. A cheaper option is just tilting the seats in the automobiles. As children are the most vulnerable group of such kind of interference, the authors propose a special construction of a tilting child seat. The seat is designed, built and tested in real road conditions. Results from road and proving ground tests, showing a significant reduction of the lateral acceleration when using a tilting child seat, are shown in the paper.

No abstract

No abstract

Abstract. In this paper a multibody dynamic model of a compact wheel loader is created. This model includes the sprung and the unsprung masses of the tractor and the mass of the bucket. Results for the natural frequencies and the accelerations of the dynamic system are obtained. The dynamic model is verified by comparing the calculated results with the ground test results.

In the present work, a methodology has been developed that allows the study of some parameters of heavy truck traffic. The study uses typical road sections of the suburban road network in which they are determined by average speeds, average fuel consumption and their impact on environmental performance. Specifically, the study was performed on road infrastructure outside the settlements in Bulgaria. In the study, a road infrastructure is divided into three main groups – road infrastructure with roads of the first and second category, as well as highway ones. The research also takes into account the operation of the truck in overcoming both positive and negative slopes. An experimental study was performed for the three types of sections. For them, the speeds of movement in typical time zones, fuel consumption, the speed of the exhaust gases and environmental indicators were measured. The work also looks for the corresponding ratios of the measured parameters for the different routes. The study also measures the exhaust flow rates. Exhaust gas temperatures are also measured at certain points along the route. This is related to the engine operating modes and its direct impact on the environment. The speed of the gases is different in the different speed regimes of the vehicle. The percentage content of the various constituents and their temperatures in the exhaust gases and the knowledge of the velocity of the exit flow make it possible to determine the volumes or quantities of harmful emissions released into the atmosphere. The developed methodology and the performed research can be used for evaluation of the work of the trucks for a certain type of transport network. It allows to determine the efficiency of the vehicle when choosing different transport routes.