Abstract

International audience; The increase in air traffic and the limited capacity of air traffic control services force us to think of a new way in which to control aircraft. An innovative ATM concept, called Sector-Less Air Traffic Management, has been defined by the Eurocontrol Experimental Centre. In this concept the role of the controller is radically different from the current one : instead of having controllers controlling a sector, controllers would be responsible for a certain number of aircraft from departure to arrival in terminal areas. The aim of this paper is to redesign the European en-route network in order to make this new way of controlling aircraft possible and to provide an aeroplane with the shortest route possible by providing a new route network. The approach proposed here is, starting from scratch, to provide a very simple route network and to improve it by using optimisation algorithm. A generated route network will be evaluated in terms of length of trajectories weighted by the amount of aeroplanes using them and then compare it with the direct route network and the current one. Using this tool and a fast time air traffic simulator, the Sector-Less concept will be able to be evaluated in terms of capacity and delay due to conflict. This also provides the route density of the network for this concept. The results of various simulations performed on the best route network generated so far will be presented.

Abstract

International audience; The resolution of conflicts between n aircraft is highly combinational and cannot be optimally solved using classical mathematical optimization techniques. Using a priority order to solve a n-aircraft conflict is much easier but the solution is not optimal. FACES (free-flight autonomous coordinated en route solver) is a model for coordinated on-board sequential conflict solving. In this project, conflict-free trajectories are obtained by applying elementary maneuvers to each aircraft, sequentially, according to some priority order. In this paper, a comparative study on a set of proposed priority heuristics to provide a suitable priority order is presented, and aggregated heuristics are compared according to some criteria. The conflict solver FACES using heuristics is tested in en-route upper airspace within an air traffic simulator using real traffic data.

Abstract

International audience; This paper presents a new method for 3D cutting of geometrical space with application to airspace sectoring. This problem comes from the air traffic management but the proposed method may be applied to many other areas. This problem consists in finding a cutting of a 3D volume into sectors in order to balance the weights of sectors and which minimizes the flow cut on sector boundaries. A mathematical modeling of this problem has been proposed for which state space, objective functions and constraints are defined. The complexity of such problem being NP_Hard, stochastic optimization have been used to address it. An Evolutionary Algorithm has been implemented for which chromosome coding and operators have been developed. Realistic problem instances have been tested on this algorithm for which the solutions produced fulfill our objective.

Abstract

International audience; This paper addresses the classical graph partitioning problem applied to the air network. We consider an air transportation network with aircraft inducing a control workload. This network has to be partitioned into K balanced sectors for which the cutting flow is minimized.

Abstract

International audience; Performance metrics in the air traffic management (ATM) community are becoming a strategic issue, and they are getting more and more attention. However, defining such metrics is a difficult problem. In this paper, we show how arithmetic simulations can be used to give performance information. We also point out that many different metrics can be defined, each of them giving different results regarding efficiency. We conclude that an extreme caution must be applied when interpreting results.

Abstract

International audience; This paper presents new concepts to address the air traffic complexity modeling problem. Two new geometrical metrics have been introduced and have been found very useful to capture typical features of traffic complexity. The covariance metric is very adapted to identify disorder in a set of speed vectors and can be applied for en route airspace (en route airspace is the airspace between airports). Similarly, the Koenig metric identifies easily the curl movement organizations and can be applied to areas around airports where air traffic control procedures impose turns on aircraft trajectories.

Abstract

International audience; This work is a twofold contribution to the analysis of conflict detection process in air traffic controllers (ATCos). The first one addresses methodological aspects and proposes a way to get responses as close as possible to controllers' actual expertise without using artifacts such as rating scales or inferring judgments from verbal material. The second objective is to compare the influence of three geometrical features of aircraft encounters and their capacity to alter an accurate perception of conflicts. The proposed methodology appeared to be useful for collecting expertise as controllers quickly appropriated it, and led to get coherent data. Its use can be envisaged when a reliable representation of mental picture of ATCos is essential. Concerning the geometrical features of aircraft trajectories, aircraft attitudes i.e., the fact they are stable, climbing of descending, entailed significant differences on detection accuracy. To a lesser extent, catch-ups and segmented trajectories showed a capacity to make an accurate perception of conflicts more difficult. These results must be interpreted as tendencies more than precise or quantified results. As the objective of this experiment was to be a pre-experiment in preparation for future collecting in the framework of the European project SESAR, a few different choices concerning the trajectories to be used in the traffic scenarios will help to precise these results.

Abstract

International audience; The fast growth of air traffic that began during the 80's raises some questions about what future air traffic control (ATC) systems need to be. A major change will probably be required in Europe within a 30 year time frame. Fortunately, recent developments in air navigation systems provide new opportunities for efficient autonomous navigation. Several studies have been conducted in order to develop automation in ATC, based either on centralized or distributed systems. An important part of the ATC task is to avoid separation losses (which are called "conflicts") between aircraft. The article presents an implementation of a reactive distributed conflict resolution method on a traffic simulator providing a realistic traffic sample. The method is described, and some results regarding its efficiency and its degradation with an increase in traffic are given. In particular, a critical traffic level appears, above which efficiency drops dramatically. This level depends on the method used; the airspace itself is not saturated.