Maik Friedrich

A guideline for integrating dynamic areas of interests in existing set-up for capturing eye movement: Looking at moving aircraft

Today, capturing the behavior of a human eye is considered a standard method for measuring the information-gathering process and thereby gaining insights into cognitive processes. Due to the dynamic character of most task environments there is still a lack of a structured and automated approach for analyzing eye movement in combination with moving objects. In this article, we present a guideline for advanced gaze analysis, called IGDAI (Integration Guideline for Dynamic Areas of Interest). The application of IGDAI allows gathering dynamic areas of interest and simplifies its combination with eye movement. The first step of IGDAI defines the basic requirements for the experimental setup including the embedding of an eye tracker. The second step covers the issue of storing the information of task environments for the dynamic AOI analysis. Implementation examples in XML are presented fulfilling the requirements for most dynamic task environments. The last step includes algorithms to combine the captured eye movement and the dynamic areas of interest. A verification study was conducted, presenting an air traffic controller environment to participants. The participants had to distinguish between different types of dynamic objects. The results show that in comparison to static areas of interest, IGDAI allows a faster and more detailed view on the distribution of eye movement.

Head up only — A design concept to enable multiple remote tower operations

Multiple remote tower operations are one concept for more cost efficient air traffic control at smaller airports. One air traffic controller (ATCO) should control traffic at two or more airports at the same time. Multiple remote tower operations for two small airports has already been successfully been validated by LFV, the Swedish air navigation service provider. As monitoring and visual observation is an important task of tower controllers, this concept raises questions on how to best support human performance when it should be applied in high traffic environments. A high fidelity study with 16 ATCOs investigated into the influence of multiple remote operations on visual attention and monitoring performance. The study was set up with high traffic volumes putting a maximum workload on the ATCO for a whole simulation run. Empirical results of eye movement measures are presented. Whilst in general visual attention distribution was not affected, less relevant events were monitored, because the visual attention was distributed over the two airports. In order to mitigate these effects, two workplace design approaches are presented - information integration and attention guidance. Advantages and challenges of the two approaches are discussed, with a focus on the impact of the design concepts on the working methods of air traffic controllers.

Discriminability of flight maneuvers and risk of false decisions derived from dual choice decision errors in a videopanorama-based remote tower work position

Future remote control of small low traffic airports (Remote Tower Operation, RTO) will rely on the replacement of the conventional control tower out-of-windows view by a panoramic digital reconstruction with high resolution and pan-tilt zoom (PTZ) video cameras as basic sensor system. This provides the required visual cues for aerodrome traffic control without a local control tower. Here we show that with a 2 arcmin-per-pixel resolution panorama system even with the use of a manually controlled (analog) PTZ camera (with PAL TV-resolution and selectable zoom factor setting) experiments under operational conditions indicate a significant increase of decision errors under RTO as compared to the conventional out-of-windows view. We quantify the corresponding discrimination difference by means of detection theory (discriminability, decision criteria) and Bayes inference (risk of false decisions) using the response errors of tower controllers with regard to dual choice decision tasks. The results extend the performance and subjective data analysis of safety related maneuvers in 11.

The influence of task load on situation awareness and control strategy in the ATC tower environment

The safe and efficient operation of air traffic is highly dependent on the performance of the Air Traffic Control Officer (ATCO). The ATCOs control the traffic within defined areas by monitoring the traffic and granting clearances. A key element in analyzing the ATCOs is their interaction with the environment through their workplace. Especially the influence of task load on their situation awareness (SA) and applied control strategy provides information on the quality of the workplace. As task load increases, controllers are able to maintain performance by using different management or compensation strategies. This article supports the evaluation of ATCO’s workplaces by focusing on whether probe techniques for assessing SA are applicable for tower control operation and for measuring the influences of increased task load on the control strategy. An experiment with nine ATCOs was conducted in a simulated real-time air traffic control environment. Different measurements for SA were applied and compared regarding their efficiency and validity. The manipulation of task load and visibility influenced the SA and control strategy at the same time. Performance metrics were selected in advance to evaluate the participant’s efficiency. SA was measured with a probe technique and an offline self-assessment method. Findings suggest that probe techniques increase the insight into the understanding of SA in comparison to self-assessment and that they are applicable to the air traffic control environment. Control strategies were derived from the information-gathering process via the eye-movement behavior and connected to task load. The results imply that SA is part of the individual performance and that increasing demand through task load is handled with an adaptation of the control strategy.

Assessing Operational Validity of Remote Tower Control in High-fidelity Tower Simulation

Abstract This paper describes a high-fidelity simulation study with twelve tower controllers within the context of the Remote Airport Traffic Control Center (RAiCe) project. Main objective was the assessment of the operational validity of remote control of one smaller airport with a high resolution video panorama system and an experimental workplace to present these video data, called RTO (Remote Tower Operation)-Console. Furthermore the information acquisition process of the controllers whilst controlling air traffic was analyzed. The central question for developing a remote workplace is: Which information does an air traffic controller need to make safe and efficient decisions while controlling an airport remotely? Until now there is no conclusive evidence which visual information tower controllers receive from their view outside the tower to control air traffic. Nevertheless for smaller airfields with little sensor technology the view outside certainly is one of the most important and comprehensive sources of information. Three variations of the workplace were varied experimentally: first a conventional 200° tower simulator, second the RTO-Console, and third the RTO-Console with additional augmentation of information on the video panorama. Objective eye tracking data were gathered during the simulations runs, together with subjective questionnaire data and interviews. Dwell times for the main information sources were determined to scrutinize the information acquisition process of the tower controller. Altogether, air traffic controllers characterize the RTO-Console as a valid work place for smaller airport. Furthermore, the eye tracking data showed that superimposition of callsigns into the video panorama reduces the head-down time onto the RADAR display.

The Evaluation of Remote Tower Visual Assistance System in Preparation of Two Design Concepts

In the last couple of years, the interest in remote tower operation systems has increased, as a concept to provide cost-efficient air traffic control service to airports. Attempts are made to stretch the concept to enable multiple remote tower control. A couple of challenges have been identified that need to be mitigated to make the concept feasible. For instance, studies revealed the disadvantage of reduced quality of the video panorama and an increased dispersion of information gathering. Design concepts were derived from the top-down and bottom-up mechanisms of human information processing to support multiple remote tower. These concepts could potentially mitigate the negative effects of a reduced quality of the video panorama and also the dispersion of information gathering. This paper focusses on the reduced quality of the video panorama and uses these design concepts to implement three visual assistance systems. These systems were tested within a laboratory experiment with 40 participants for effectiveness, efficiency, satisfaction, situation awareness, and workload. The microworld FAirControl was used to simulate an air traffic control monitoring task at a single airport. First, the visual assistance systems were compared against the baseline to assess the improvement of each system. Second, in an explorative approach, the visual assistance systems were compared to identify the advantages and disadvantages against each other. The results show that visual assistance systems can mitigate the influence of the quality-reduced video panorama. The results also indicate that usability of the visual assistance systems is crucial. Participant selective information overlay had the best overall performance.

Which metrics provide the insight needed? A selection of remote tower evaluation metrics to support a remote tower operation concept validation

This chapter describes the metrics for the validation of a Remote Tower Control workplace. The study shows how Air Traffic Control Officers (ATCOs) observe traffic from a Tower Control Working Position at Airport Erfurt-Weimar in comparison to a Remote Controller Working Position. Shadow-mode trials were used to cover perceptual, operational, and human factors aspects of a Remote Tower System, including a live video panorama and a research aircraft. The aircraft was used to fly different maneuvers within the aerodrome. These maneuvers allow insights on the detectability of an aircraft within different distances from the tower and the gathering of operation information about aircraft status. In addition, a vehicle was used to position static objects on the airfield to determine the detectability of these objects for different distances to the Control Tower (RTO-camera system). Eight ATCOs from the DFS participated in the validation exercise. Time-synchronized questionnaires for the controller working position remote (CWP remote) and the controller working position tower (CWP tower) were applied, addressing operationally relevant questions to the ATCOs. The validation exercise targets the evaluation of metrics that could help standardize the process of testing Remote Controller Working Positions. The results consider expense of realization, comparability, and feasibility as major classifications for the used metrics. Further, an approach for combining the classification into one score is presented to rank the metrics in relation to each other.

How to Evaluate Remote Tower Metrics in Connection With Weather Observations: An Extension of the Existing Metrics

Owing to the different approaches for remote tower operation, a standardized set of indicators is needed to evaluate the technical implementations at a task performance level. One of the most influential factors for air traffic control is weather. This article describes the influence of weather metrics on remote tower operations and how to validate them against each other. Weather metrics are essential to the evaluation of different remote controller working positions. Therefore, weather metrics were identified as part of a validation at the Erfurt-Weimar Airport. Air traffic control officers observed weather events at the tower control working position and the remote control working position. The eight participating air traffic control officers answered time-synchronized questionnaires at both workplaces. The questionnaires addressed operationally relevant weather events in the aerodrome. The validation experiment targeted the air traffic control officer’s ability to categorize and judge the same weather event at different workplaces. The results show the potential of standardized indicators for the evaluation of performance and the importance of weather metrics in relation to other evaluation metrics.