Citation

Kuhn W, Volker H, Kubik R. Transp. Res. Rec. 2011; 2241: 109-117.

Copyright

(Copyright © 2011, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

10.3141/2241-12

PMID

unavailable

Abstract

The planning and design process for rural roads in Germany takes place iteratively within various design stages, each followed by a subsequent approval procedure. Design engineers do not, however, have adequate aids for the technical aspects of design work (i.e., search for route, comparison of options, safety checks) apart from general rules and regulations. In Germany, a new kind of design methodology is being developed as part of a research project in which a new model concept (three-dimensional route search) is being used. Fifth-degree Bézier curves are used for the three-dimensional route, and the curves enable the curvature features of a combined curve (clothoid, circular arc, and clothoid) to be generated in the sections that require a transition curve. Three-dimensional straights can also be represented with this mathematical approach. Once the three-dimensional route has been broken down into the individual design levels, two-stage safety checks take place according to geometrical criteria (set guidelines) and the expected driving behavior (simulation). The design engineer is supported in the interactive planning and checking process by various visualization techniques (e.g., two- and three-dimensional display, simulation along the virtual driving area). The workplace simulator that has been developed combines the design methodology and hardware and software components and therefore uses the all-around process of designing, checking, driving, and assessing in a practical manner.