UTOPIA: Universal Trajectory Synchronization for Highly Predictable Arrivals Enabled by Full Automation.

Technische Universität Dresden

Boeing Research & Technology Europe

Barco-Orthogon GmbH (Barco)




The solutions proposed in UTOPIA are covering three innovative areas. Formal models of trajectory data and trajectory synchronization protocols for heterogeneous systems in an automated environment will extend the concept of 4D trajectories to n-dimensional trajectories to study communication mechanisms needed for trajectory synchronization. Furthermore, uncertainty sources and their propagation in die n-dimensional trajectories will be investigated, considering also system disruptions, to understand uncertainty effects and the different tactical or strategic autonomous measurements to manage them. Advanced trajectory management algorithms and ground synchronization functions based on the formal n-dimensional trajectory data and uncertainty models developed and used to design advanced arrival management algorithms and air-ground communication protocols.




One of the greatest challenges that the future ATM system will need to face in the next decades is the integration of new airspace users and the continuous increase in delegating capacity and safety critical traffic management functions to automated systems. The accommodation of these new airspace users, which will have to coexist with conventional users, a widely reorganized airspace and the increased level of automation will necessarily need a paradigm shift with regard to the trajectory management functions already foreseen in the SESAR master plan for 2020. The objective of the UTOPIA project is to provide a better understanding of which trajectory management functions will be needed to deal with clearly heterogeneous traffic when those functions are executed by autonomous ATM systems and humans involved in the decision and execution of the air traffic management actions. In particular, the study executed in this project will focus on the data models, synchronization requirements and algorithms needed to ensure the safe management of merging traffic, executed by an autonomous arrival management function acting as separator. The converging flows of traffic that will be studied comprise heterogeneous airborne systems, in particular, unmanned air-vehicles and advanced and legacy flight management systems, representing airspace users with different synchronization capabilities.

In addition to the theoretical research that will be performed in the areas of formal languages, trajectory synchronization and uncertainty modeling and is described in the following chapters, we will validate the concepts proposed by means of a demonstrator. The UTOPIA demonstrator will simulate the interaction of different airborne systems with an autonomous arrival management. These airborne systems represent different possible synchronization levels in terms of the information and protocols used. The arrival management will use the information derived from the airborne systems and perform separation, sequencing and scheduling of the traffic flow taking into account the associated uncertainty and disruption models. In principle, this demonstrator will include a real Boeing 737 Flight Management System (FMS), a software based Airbus A320 FMS, different simulated commercial aircraft and unmanned aerial vehicles and a real Barco Arrival Manager adapted to this new paradigm. The crucial objective of UTOPIA is to help understanding what level of integration and robustness is needed to achieve the execution of fully autonomous operations with heterogeneous traffic with regard to aircraft types and equipment installed. We expect that the conclusions of this project will serve to establish the research agenda to achieve the seamless integration of any airspace user with autonomous or semi-autonomous ground tools.




The research objectives of UTOPIA, which also represent the main contributions to the expected SESAR 2020 state of the art, are the following:

  • New Air-ground trajectory synchronization concept based on the use of a formal language to describe nD trajectories. This approach will allow any future airspace user (AU) and trajectory based ground system to share consistent views of any aspect (e.g. position, time, and configuration) of the AUs behavior. The use of a formal language will ensure the unambiguity of the information exchanged and moreover, the deterministic interpretation of that information by any trajectory-based system. This trajectory synchronization concept relies on the fact of the existence of a common meta language that can serve to formally express any trajectory related aspect.
  • Uncertainty and Disruption Modeling: Airborne uncertainty modeling based on classified disruptions which will hamper plan compliance (e.g. meteorological disturbance patterns, incident scenarios on ground and in the air, here the TMA, propagation of uncertainty in nDTs and effects on trajectory management functions (trajectory synchronization and arrival management);
  • Automated arrival management: Study the combination of trajectory synchronization with advanced conflict detection/separation assurance either ground based or on-board in order to prepare the automated arrival guidance for the different airspace users equipped with diverse capabilities. This will include management of uncertainty and user preferences;
  • Ensuring robustness in automated trajectory management functions for heterogeneous traffic: Robustness under uncertainty, consequences of different kinds of communication disruptions, failure mode analysis or fall-back strategies for highly automated systems.


In addition to these theoretical contributions, a demonstrator will be developed to validate the trajectory data and uncertainty models proposed, and all the trajectory management algorithms developed to support automated operations of heterogeneous traffic in the TMA. This demonstrator will allow remote ATM systems to interconnect in to exchange trajectory-related information in a network-centric manner. This demonstrator will initially include the interfaces required to allow real FMSs (B737 and A320) and simulated AUs (UAVs and legacy and advanced FMSs) to publish their trajectory information, and the necessary interfaces to enable the advanced algorithms implemented in an advanced Arrival Management infrastructure to interact with the demonstrator. The demonstrator shall also serve as an open test bed for any researcher to prove and prototype different algorithms for the trajectory management of heterogeneous traffic.




The basic structure of the project starts with a definition of the future ATM concept, the UTOPIA concept of operations, to be studied along the project, performing a detailed analysis of the expected functionality of the automated systems in 2020 and identifying gaps for reaching full automated capability for strategic trajectory management of heterogeneous airborne systems.


To support the objective of full automated managing of heterogeneous traffic, a study of a formal definition of the trajectory information to be handled will be performed. This study will be focused on the identification of the information needed for describing an nD trajectory and the definition of a formal structure to express this information unambiguously, based on the Theory of Formal Languages. This will permit the deterministic interpretation of that information by autonomous systems.


The idea of having a strict mean of encoding the trajectory information without ambiguity leans on the assumption of knowing the effect and propagation of the associated uncertainty to the nD trajectory information. A dedicated study is planned to identify the relevant sources of uncertainty that may impact the air-ground synchronization and their effects on the decision making process that will be performed by a fully automated tool.


Once a clear understanding of how to express univocally an nD trajectory and the influence of uncertainty factors have been established, the procedures of how a full automated arrival manager will manage them and how this tool will evaluate the different alternatives will be specified.

Finally, specific cases for the concept validation will be analyzed using a simulation platform that will be developed accordingly. This platform will serve to validate the concept definition for managing nD trajectories of heterogeneous traffic by a full automated arrival manager tool considering the uncertainty related to this nD trajectory. The simulation to be performed will be circumscribed to converging traffic around the adopted Terminal Maneuvering Area assuming simultaneous de-confliction and scheduling.