Congestion and pollution are two ever increasing problems in our would of urbanization. Bicycling is one of the most sustainable means of transport and it is a great way of reducing congestion in cities. Route planners which brings out the best aspects of bicycling and promotes them during route calculation is a good way of increasing the attractiveness of bicycling.
When planning a route today there are online services which can perform regular route planning taking only the length of each route into consideration. The objective of this paper is to introduce an alternative way of performing route planning using other traits than just the length when determining the best route.
This paper introduces an algorithm which is able to perform route planning which takes several aspects into account. The algorithm uses two additional attributes together with the length to determine the cost of traversing each polyline. The additional attributes used are named nature and slope index. The nature index is supposed to give a numerical representation of the environment surrounding the polyline, this is calculated using a land cover map and a buffer around each polyline which represents its neighborhood.
The nature index is used to make the route planner prefer more beautiful paths along water, park or forests over shorter ones which passes through high density development for instance. The slope index is stores the average slope of the entire polyline. It is calculated using a digital elevation model and dividing the height difference between the start and end point with the length resulting in a slope percentage. The slope index is used to find paths which are as flat as possible.
The two indexes together with the length attribute are then combined in seven different cost functions, each weighting the attributes differently to accommodate different preferences. Each of the calculated costs is stored as an attribute for every polyline. Networks on which route planning can be performed are then built using these cost attributes.
The resulting networks are inspected visually using the indexes as display factors and determined to be accurate. Route planning using these networks results routes do follow areas with higher nature index and avoids slopes. In this paper a few examples of routes with an orthophoto as background are included which clearly illustrates that the nature index promotes the correct type of environment.
Source: KTH
Author: Plynning, Emil