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Sustainable development and sustainable transport are becoming of higher and higher importance. A scientific approach to sustainable development analysis means, first of all, identification of relevant indicators. Based on literature review and regional professionals’ view, a total of 90 indicators have been chosen. They have been structured in five hierarchic levels. A total of five personal transport means alternatives have been analyzed in the research. The AHP method of analysis has been employed in which 75 professionals from the Western Balkan countries have filled appropriate questionnaire. The research presents their opinion about the capacity of each of the alternatives to contribute to the sustainable transport in the region, but also puts a light on perception of the professionals on importance of chosen indicators. The results of this research could be used for further research and could also help to decision making levels regarding sustainable transport and sustainable development.

Transportation and traffic affect all the aspects of everyday life. To better understand traffic dynamics traffic models are developed. On microscopic level, carfollowing models are developed and improved during long period of time. They are used in traffic simulation tools or are the basis for operation in some advanced vehicle systems. Carfollowing models describe traffic dynamics through movement of individual vehicle-driver units. This paper compares Gipps model and Intelligent Driver Model (IDM) as carfollowing models based on driving strategies. These models are derived based on assumptions such as keeping safe distance from the leading vehicle, driving at a desired speed and producing accelerations within a comfortable range. The models are implemented and simulated in MATLAB environment and the results are discussed in terms of the ability to reproduce real driving behaviour in car following scenarios.

The opinion of the operators of the working machines in today’s world is much more valued than in the past. Their comfort, safety and satisfaction during the working hours can be crucial in the decision making process of buying new working machine. Therefore, in this research paper the vertical dynamics and ride comfort of an electric street sweeper would be analysed by using a multibody dynamic model. The model is created using MSC. ADAMS, based on a real electric street sweeper. In order to test the ride comfort of the existing model, a road profile is modelled, according to the standard ISO 8608. The virtual tests are conducted while the vehicle is traveling with maximum velocity of 40 km/h, achieved during transit and lower velocities which are achieved during the operating hours of the machine. An optimization of the suspension system of the real electric sweeper is made, by targeting its components location and positioning, stiffness and damping characteristics. This results in improved ride comfort and smaller root mean square (RMS) values of vertical acceleration of the driver seat. These improvements would influence on operator’s better comfort and health. Results are presented using comparative diagrams of the original and optimised model.

Advances in vehicle technologies brought changes into architectures of integration of chassis control systems. Alongside other improvements, integration can provide better vehicle handling, stability and safety. Different chassis control systems can use different control methods. Considering while in motion vehicle has movements in longitudinal, lateral and vertical direction, different control systems target different motion. If there is no coordination among active control systems, interaction and performance conflict can arise. This paper presents coordination of three control systems: electronic stability control (ESC), active front steering control (AFSC) and active suspension normal force control (ASNF). ESC is actually direct yaw and anti-roll control using selective wheel braking. ASNF is considered only on front axle. All systems use fuzzy-logic as a control method. Vehicle is presented as 14-DOF nonlinear full vehicle model and for the control purposes 3-DOF reference model was introduced. Emphasis was given on vehicle parameters characterizing dynamic behavior in longitudinal and lateral direction. Benefits of coordinated action of the three systems can be seen from the results gained through simulation of cornering event and single lane change in Matlab/Simulink. Coordinated control adds to the action of ESC itself, resulting in improved stability and handling, and thus safety of the vehicle.