Resumen
Route planning in urban public transport systems constitutes a common decision problem faced by travelers. Therefore, building Advanced Traveler Information Systems (ATIS) that provide passengers with pre-trip information on navigating through the network has become a certain need. Since passengers do not only seek a short-time travel, but they endeavor to optimize other criteria such as cost and effort, an efficient routing system should incorporate a multiobjective analysis for both routes and transport modes. We propose in this paper a new formulation that adequately allows representing a public transit network, as well as, yielding correct results when applying routing algorithms. Based on this formulation, we develop a multicriteria routing algorithm to determine the entire set of nondominated solutions to solve an itinerary planning problem. We introduce also several enhancement strategies to accelerate the algorithm's search process. As transportation modes, we focus on Railway, bus, tram and pedestrian. As optimization criteria, we use travel time, number of transfers and the total walking time. Experimental results have been assessed by solving real life itinerary problems defined on the transport network of the city of Paris and its suburbs. Results indicate that test problems were solved within reasonable amount of time and the new approach is efficient enough to be integrated within a real world journey-planning system.