The authors examined how visibility analysis may be used to calculate the extent of the route ahead visible to a motorist. To do this a Digital Surface Model sourced from a LiDAR dataset was used, which includes building and vegetation profiles as well as topography. Once the route had been designated the visibility along the path is modelled, in the direction of travel, from the driver's viewpoint. The visibility analysis considers all surrounding objects during the calculation, but reports only how far ahead the route may be viewed, and not the total landscape area visible. The map accompanying the article shows the results from using this method for a route in Christchurch, New Zealand, from which the authors identified a number of interesting results along the route. This method may be used such that navigational devices customise announcements to the most opportune times when the driver's workload is minimal and decision points are in view, rather than at predefined distances. It could also be used to notify the driver of the safest overtaking locations or those areas of limited visibility. (Author/publisher)
Abstract