Conflict avoidance: 0-1 linear models for conflict detection & resolution

Abstract

The Conflict Detection and Resolution Problem for Air Traffic Flow Management consists of deciding the best strategy for airborne aircraft so that there is guarantee that no conflict takes place, i.e., all aircraft maintain the minimum safety distance at every time instant. Two integer linear optimization models for conflict avoidance between any number of aircraft in the airspace are proposed, the first being a pure 0-1 linear which avoids conflicts by means of altitude changes, and the second a mixed 0-1 linear whose strategy is based on altitude and speed changes. Several objective functions are established. Due to the small elapsed time that is required for solving both problems, the approach can be used in real time by using state-of-the-art mixed integer linear optimization software.

A space-discretized mixed-integer linear model for air-conflict resolution with speed and heading maneuvers

“…Separation is then characterized by the gap between fly over times at conflict points. This technique is used to develop models that are restricted to speed maneuvers in [27,2,21].…”

“…However, the sampling points directly depend on the predicted trajectories, which makes it hard to represent the geographical deviations that would result from heading maneuvers. For this reason, models based on a spatial discretization allow only speed maneuvers [21,7] or also include instantaneous altitude changes reflecting a flight-level assignment rather than dynamic altitude maneuvers [27,2]. The drawback of this assumption is that aircraft cannot dramatically modify their speed at will for reasons such as aircraft performance, passenger comfort, fuel consumption, or delay adjustments.…”

“…These points, referred to as conflict points, are the points where the trajectories of two conflicting aircraft intersect. Although it is not explicitly identified as such, a space discretization is used in [27,2,7] to derive a model involving only speed maneuvers. The new difficulty that is tackled here is the inclusion of heading maneuvers.…”

“…These maneuvers are not appropriate for short-term separation, since they are uncomfortable for passengers, inefficient in terms of fuel consumption, and hard for ATC operators to monitor. However, flight-level assignments could be included as in [27,2]. They would make it necessary to simultaneously consider several flight levels, but no additional difficulty would arise since they do not model the dynamics of the aircraft.…”

Symmetry-Based Conflict Detection and Resolution Method towards Web3D-based Collaborative Design

“…Thus, it is necessary to ensure the interactivity and real-time performance of this design platform. In this platform, Conflict detection (CD) [7] and conflict resolution (CR) [8,9] are important [10][11][12][13][14]. This paper studies For most of the authority mechanisms, e.g., lock mechanism, traffic light mechanism and floor mechanism [17][18][19][20][21][22][23][24][25], designers must apply for system's permissions before modifying collaborative models, so they can make all the operations execute sequentially and ensure data consistency among all workstations.…”