Joost Ellerbroek

Design of an airborne three-dimensional separation assistance display

In the context of the NextGen and SESAR future airspace programmes, this paper describes a concept for an Airborne Separation Assurance (ASAS) display, that is designed to aid pilots in their task of self-separation, by visualizing the possibilities for conflict resolution that the airspace provides. This work is part of an ongoing research towards an ecological design of a separation assistance interface that can present all the relevant properties of the spatio-temporal separation problem. A work-domain analysis is described from which several perspective projections of traffic properties and travel constraints are derived. A display concept is proposed that presents heading and altitude action possibilities in a flight-path angle - track angle action space. Key issues in the current design are discussed, with recommendations for future work.

Beyond Ecological Interface Design: Lessons From Concerns and Misconceptions

The ecological interface design (EID) paradigm was introduced in the process control domain 25 years ago by Kim Vicente and Jens Rasmussen, as a way to help operators cope with system complexity and events unanticipated in the design of automated control systems. Since that time, this perspective has sparked interest in other safety-critical sociotechnical domains where humans cooperate with computerized systems to ensure safe and efficient system behavior. Many of our own, but also other explorations have, however, resulted in several usability concerns and misconceptions about the EID perspective as a viable design approach. This paper discusses some of these concerns and misconceptions, where the final goal is to get past the EID label and to consider the general lessons relative to the demands and opportunities that advanced information technologies offer and complex systems require. This paper concludes with a preliminary outlook for the future of EID, where it is anticipated that the adjective “ecological” will become increasingly redundant, as the focus on supporting “productive thinking” becomes the dominant paradigm for engineering representations.

Design of a Coplanar Airborne Separation Display

This paper describes a concept for a coplanar airborne self-separation display, which is designed to aid pilots in their separation task, by visualizing the possibilities for conflict resolution that the airspace provides. This study is a part of an ongoing research toward the design of a constraint-based 3-D separation assistance interface that can present all the relevant properties of the spatiotemporal separation problem. A display concept is proposed that presents speed, heading, and altitude action possibilities in two planar projections of the maneuver action space. The interface also visualizes how these projections interact with each other.

Experimental Evaluation of a Coplanar Airborne Separation Display

Two experiments, an active conflict resolution task and a passive situation awareness assessment, were conducted that compared two versions of a constraint-based coplanar airborne separation assistance display. A baseline display showed a maneuver space based on 2-D projections of traffic and performance constraints. A second augmented display also incorporated cutting planes that take the dimension orthogonal to the projection into account, thereby providing a more precise visualization of traffic constraints. Results showed that although pilots performed well with either display, the augmented display scored consistently better in terms of performance, efficiency of conflict resolutions, the amount of errors in the initial resolutions, and the level of situation awareness compared with the baseline display. On the other hand, more losses of separation were found with the augmented display, as pilots tried to maximize the maneuvering efficiency according to the precision with which constraints were visualized.

The Effect of Traffic Complexity on the Development of Near Misses on the North Sea

Vessel traffic is changing due to changing transport demands, larger ships, and new use of sea space, such as windmill parks. This may have an effect on the risks at sea. This paper uses ship state information provided by automatic identification system-messages to analyze the traffic on the North Sea. From the ship-state information conflict situations are selected, i.e., situations where the ships need to maneuver to avoid collision. In addition, situations of near-miss collisions are calculated. It was found that complex conflicts lead to more near misses. It was also found that near misses are not spread evenly over the sea but are concentrated in a number of specific locations. These findings may be important for the design of route structures for ships, as well as for investigations into methods to resolve complex conflict situations.

Taxonomy of Conflict Detection and Resolution Approaches for Unmanned Aerial Vehicle in an Integrated Airspace

This paper proposes a taxonomy of conflict detection and resolution (CD&R) approaches for operating unmanned aerial vehicles (UAVs) in an integrated airspace. Possible approaches for UAVs are surveyed and broken down based on their types of surveillance, coordination, maneuvering, and autonomy. The factors are combined back selectively, with regard to their feasibility for operation in an integrated airspace, into several “generic approaches” that form the CD&R taxonomy. These generic approaches are then attributed to a number of available methods in the literature to determine their position in the overall CD&R scheme. The attribution shows that many proposed methods are actually unsuitable for operation in an integrated airspace. Furthermore, some part of the taxonomy does not have an adequate representative in the literature, suggesting the need to concentrate UAV CD&R research more in those particular parts. Finally, a multilayered CD&R architecture is built from the taxonomy, implementing the concept of defense in depth to ensure safe operation of UAVs in an integrated civil airspace.

Three-Dimensional Velocity Obstacle Method for Uncoordinated Avoidance Maneuvers of Unmanned Aerial Vehicles

This paper proposes a novel avoidance method called the three-dimensional velocity obstacle method. The method is designed for unmanned aerial vehicle applications, in particular to autonomously handle uncoordinated multiple encounters in an integrated airspace, by exploiting the limited space in a three-dimensional manner. The method is a three-dimensional extension of the velocity obstacle method that can reactively generate an avoidance maneuver by changing the vehicle velocity vector based on the encounter geometry. Adverse maneuvers of the obstacle are anticipated by introducing the concept of a buffer velocity set, which ensures that the ownship will diverge with sufficient space in case of sudden imminence. A three-dimensional resolution is generated by choosing the right plane for avoidance, in which the unmanned aerial vehicle conducts a pure turning maneuver. Implementation of the three-dimensional velocity obstacle method is tested in several simulations that demonstrate its capability to resol...

Identification of the Roles of Yaw and Sway Motion in Helicopter Yaw Control Tasks

A set of experiments has been conducted to investigate the relative effect of translational and rotational motion cues on pilot performance. Two helicopter yaw control tasks were performed on the SIMONA Research Simulator; a yaw capture task, and a target tracking task with simulated turbulence. The yaw capture task was a repetition of a task performed previously by Schroeder and Grant at two different simulator facilities. Shaping filters and added delays were used to match simulator characteristics with the previous experiments. In contrast to Schroeder and Grant’s conclusions, results from the current study show more equal contributions of yaw and sway motion on performance and subjective simulator motion fidelity. Analyses of the different vestibular cues using multi-loop pilot models, estimated from measurement data from the target tracking task, also indicate comparable utilization of the yaw and sway motion cues. Nomenclature �d Disturbance forcing function �p

Effects of transparency on the acceptance of automated resolution advisories

To lower the workload and increase the productivity of air traffic controllers in future scenarios, decision-support systems that functions on a higher level of control authority would be desired. However, increasing the control authority of automation asks for some important considerations in terms of design to ensure effective human-machine coordination. One of the factors that is hypothesized to affect human-machine collaboration, and one that is often overlooked in the design of such systems, is the solution transparency offered by the automated system. That is, when an automated system reveals some of its inner workings, it is expected to promote better system understanding and an increased acceptance of resolution advisories offered by that system. To this end, this paper investigates the effects of automation transparency on the acceptance of automated resolution advisories in conflict detection and resolution task for air traffic controllers. An exploratory experiment, featuring twelve aerospace students, was performed to study these effects. The results indicated that no main effects of transparency on acceptance were found, but also that there was a significant interaction effect between conflict geometry and transparency. For future research, an experiment is proposed with professional air traffic controllers and a larger sample size to increase the power of the statistics.

Three-dimensional velocity obstacle method for UAV deconflicting maneuvers

Autonomous systems are required in order to enable UAVs to conduct self-separation and collision avoidance, especially for flights within the civil airspace system. A method called the Velocity Obstacle Method can provide the necessary situational awareness for UAVs in a dynamic environment, and can help to generate a deconflicting maneuver.This paper focuses on the assessment of the Velocity Obstacle Method application and its ability to resolve various conflict situations in three dimensional space. This assessment results in a redefinition of the criteria of avoidance. A novel technique is introduced to support the avoidance decision, by representing the conflict situation in various avoidance-planes. Several new definitions to support the method are introduced. This method is then implemented in three-dimensional simulations for UAVs in cases of conflict, in which more than one option of resolution is provided.