Roland Kovacs

Analysis and experimental verification of faulty network modes in an autonomous vehicle string

Advanced autonomous vehicle strings rely on inter-vehicle communication in order to decrease the necessary safety gap so that fuel consumption can be decreased and road capacity can be increased. In case of failures of some communication channels, the corresponding back-up control strategy must be switched on. Maximal spacing errors of such back-up modes are analyzed and compared. Robustness to platoon heterogeneity and communication delays are considered. The main conclusion we can draw is that, in the full communication mode, satisfactory spacing performance can be achieved by using simple output-feedback controllers designed without detailed knowledge on engine/brake characteristics, only utilizing the existing services available today in every commercial heavy trucks with automatic gearbox. Experimental verification of the designed controllers are presented.

Modeling of commercial vehicles for vehicle dynamics control development

Commercial vehicle modeling strategies are presented in this paper. Models created are suitable for vehicle dynamics control development, computationally efficient, and well-structured. Important feature of the models is that they can easily support a huge number of possible vehicle variants with different geometrical and structural requirements. Model is built-up in a multi-body structure. This paper details the modeling of the vehicle frame and the suspension and gives brief insight into the tire modeling for which a brush-model approach is used. Finally, simulation results are presented.

Congestion Forecast – A Societal Opportunity

Information technological, economical, financial, legal and institutional aspects influence congestion forecast systems system setups. First, several solutions for the individual problem areas are developed and evaluated. Then, alternatives for congestion forecast systems are defined as coherent solution sets of the depicted problem areas. The information technological key issue is data quality. Successful introduction of such a system in terms of economy and finances deeply depends on the technological service provided. Legal and institutional solutions target in the first line data privacy requirements. Finally, the most attractive solution is outlined.

Concept validation of an automatic passenger counting system for trams

The system shown addresses the problem of automatic passenger counting (APC) in trams with high utilization, uncoordinated boarding and lacking air suspension. Conventional APC systems do not provide sufficient accuracy under these conditions. A concept for determining the total weight of the vehicle using only data already acquired on the vehicle or available from other sources has been worked out. The essence of the concept is that the actual weight of the vehicle can be calculated from the driving dynamics, traction and energetic data of the vehicle and the track geometry. The result can be used to calculate the weight of the passengers exactly and to estimate their number at specific capacity utilization with sufficient accuracy. The theoretical concept has been proven with measurements carried out on a tramline in Budapest.