Hierarchical fuzzy controller based map-matching algorithm

Map-matching,which can integrate vehicle positioning data with digital road network,is an important positioning technique in the vehicle navigation system.A novel map-matching algorithm utilizing current positioning point as well as some history positioning points was proposed to improve the disadvantage in the inadequate information of map-matching algorithm by only using the current positioning point.A distance between two trajectory curves was defined by an average Frechet distance measure,and a hierarchical fuzzy controller was designed to perform uncertain reasoning for map-matching for this system.It can simplify the reasoning rules and improve the efficiency of calculation.Then,the credibility,P,was derived as an estimate index for the map-matching algorithm.The proposed algorithm could provide not only warning information to the user when mismatching occurred,but also a means of fast recovery from failure.The results of experiments demonstrate the effectiveness of the proposed algorithm.