Using High-resolution Digital Elevation Model for Computer-aided Forest Road Design

The current forest road design systems are not capable of making computer-aided design judgments such as automated generation of alternative grade lines, best fitting vertical alignment for minimizing the total road costs, or consider environmental impact. A three dimensional (3D) forest road design model was developed as a decision support tool that provides a designer with a quick evaluation of alternative road paths. In the model, initial trial routes are generated by “tracing” the possible paths using computer cursor on a 3D image of the terrain. The model integrates two optimization techniques (linear programming and a heuristic approach) for selection of a vertical alignment with the lowest total costs, while conforming to environmental requirements. Improved 3D OpenGL accelerator is used to display and render 3D images of the terrain in real-time, based on high-resolution Digital Elevation Model (DEM) data. LIDAR (Light Detection and Ranging), one of the fastest growing systems in the field, can provide a high-resolution and accurate DEM of forested areas. It is expected to provide even better accuracy in the near future. The development of the road design model incorporating modern graphics capability, advanced remote sensing technologies, improved software languages, modern optimization techniques, and environmental considerations will improve the design process for forest roads.