Report on the CHI'99 workshop on real-time decision support computer-human interaction

Aviation performance depends on education and training of pilots and air traffic controllers (ATCOs) on technical, procedural, crisis management, decision making, leadership and communication skills. Recent incidents and studies, however, show crew members may be caught unaware and errors in human judgement can still occur in air traffic control (ATC) systems even more so in the presence of cyberattacks. This paper focuses on raising situation awareness and decision making of ATCOs with cyberattacks impacting operations in next-generation ATC systems. Our goal is to investigate crew-based cyber security as a layer in making ATC systems resilient to cyber and cyber-physical attacks. Automatic Dependent Surveillance Broadcast (ADS-B) technology is used as the basis of our preliminary investigation due to its widely known security concerns and central role in ATC systems. We present experimental study considerations for assessing cyber readiness and improving training of ATCOs. We propose a Kalman filter based cyber alarm solution approach for a machine learning based aid for ATCOs towards early cyberattack detection and incident response in ATC systems.

With growing air traffic density, air-traffic controllers (ATCOs) are facing more challenges in interpreting and analyzing air traffic information. As one of the solutions to this problem, automation supports such as tactile human computer interface, interactive 3D radar displays, and conflict resolution aid (CRA) are proposed for the enhancement of the current air traffic control (ATC) systems. To evaluate the proposed ATC systems, questionnaires are commonly used to get the feedback from ATCOs. However, the questionnaires are usually administered upon completion of each ATC simulation task thus provide only overall ratings towards the new ATC systems. In this paper, we propose and implement a novel Electroencephalogram (EEG)-based neurocognitive tools for evaluation of ATC systems. The nature of EEG-based technique is that the brain states can be monitored in a high resolution time, fitting the nature of time-critical ATC tasks. Thus, such EEG-based human factors study allows for real-time monitoring of ATCOs' mental workload during the task performance in ATC systems. We designed and conducted an experiment to evaluate the costs and benefits of the CRA and tactile user interface in future ATC systems. Thirty six participants participated in the experiment and were assigned into three groups of different display modes: Non-Display, Display, and Trajectory Prediction. In each group, three CRA conditions were given: Manual, Reliable and Unreliable. The EEG data were recorded during the tasks, and the traditional workload evaluation method NASA Task Load Index (TLX) was administered at the end of each task. The result shows that the ratings obtained from NASA TLX and from the EEG labeling are highly correlated. Thus, the EEG-based system is reliable to recognize workload during the task performance. With the proposed EEG-based system, we found that 1) relatively high workload was observed at the beginning of the experiment in each group which could be due to participants' unfamiliarity with the interfaces; 2) participants in the trajectory prediction group had much higher workload as compared to vertical display and non-display groups, which could be attributed to its complexity. The changes of workload are due to interaction between the type of display modes and time (p<0.05); 3) workload varied slightly with different CRA setting. The results show that the proposed EEG-based system for human factors study can provide better understanding of real-time mental workload changes during the task performance in new ATC systems, therefore enables the evaluation of current and future ATC systems.

The human-machine problem in automation systems is generally limited to control tasks in self-contained (i.e., clearly definable) technical processes. Integrated air traffic management and control systems, however, are not definable processes, as the amount and the purpose of traffic vary. Persons charged by different organizations try to override the other claims by means of their automation equipment. In order to avoid dangerous competition, there are some requirements for the design of the automation system. Analyzing the general air traffic management problem, the influence of the system architecture on the verification and validation of the system function is to be shown.

The identification of backup radio sites, to increase the availability of the future air/ground (A/G) air traffic control (ATC) systems, is investigated, When there is an A/G communications failure, due to a radio site or an ATC controller access failure, another site (or sites) provides the service. The backup site should be capable of providing full coverage of the desired airspace known as the service volume. Meeting the full coverage conditions by one site or a group of sites is analyzed. It is concluded that identification of one site providing full coverage can be determined easily. The identification of a group of sites, each with partial coverage and providing full coverage is analyzed in detail. An algorithm involving both analytical and numerical approaches is described. It determines if two radio sites with given geographical coordinates, and each with partial coverage of a given cylindrical service volume, can provide full coverage. This algorithm can be implemented as a computer program to process a database of radio sites.

A path object is a set of instructions plus the values of associated parameters that would be used by an aircraft’s flight management system (FMS) or area navigation (RNAV) computer to construct a flight trajectory on the basis of the values of the parameters provided by the pilot or air traffic control (ATC) system. The concept of path objects and its applicability for development of FMS- or RNAV-based flight paths for aircraft routes are described. The use of path objects requires only a small number of parameters for specification of an RNAV route, and the computer then calculates the resulting flight path. Because most RNAV routes are just variations of the same basic shapes, many RNAV routes can be generated from a single path object by changing just one or two parameters. This offers the capability to reduce the size of the navigation database by a significant amount. This also allows the dynamic alteration of three-dimensional FMS-RNAV routes instead of radar vectoring, which represents a significant improvement in ATC procedures. Because of the compact expressions for the path objects, these procedures could be used in a voice communications environment as well as a data link environment. A path object can be thought of as a high-level language with which aircraft and ATC systems communicate flight path intentions. The concept of FMS- or RNAV-stored path objects is a change in thinking about the role of avionics technology. It offers a means of including the precision of the FMS-RNAV technology in the ATC system during the transition from today’s system to the future’s fully automated control system. This is an enabling technology that improves the ability to use and maintain FMS-RNAV in its role as a vital component of the ATC system. It has the potential to enhance future air traffic management-communication navigation surveillance concepts and applications.

An air traffic control system’s main function is to separate aircraft. The computer supporting the system assists the air traffic controllers by generating a conflict alert whenever it predicts that two aircraft are about to get too close to each other. The performance of the conflict alert function is a key element to the overall functioning of the air traffic control system. A set of metrics has been designed to measure the conflict alerting performance of an aircraft traffic control system. The key factors are the missed alert rate and the false alert rate. However there are several secondary factors that are essential to measuring the performance, especially in a simulation environment. This paper describes a set of metrics that have been developed to evaluate the performance of the FAA’s en route aircraft traffic control system. They have been applied to the existing system, the Host Computer System, and will be used to establish metrics for the new system now under development, the En Route Automation Modernization system. The metrics are calculated by post processing recorded data that has been produced by running a real time simulation of the air traffic system without controllers, using as input field recorded aircraft data that has been time shifted to induce aircraft-to-aircraft conflicts.

Based on a long-term prediction by the International Civil Aviation Organization indicating steady increases in air traffic demand throughout the world, the workloads of air traffic controllers are expected to continuously increase. Air traffic control and management (ATC/M) includes the processing of various unstructured composite data along with the real-time visualization of aircraft data. To prepare for future air traffic, research and development intended to effectively present various complex navigation data to air traffic controllers is necessary. This paper presents a mixed reality-based air traffic control system for the improvement of and support for air traffic controllers’ workflow using mixed reality technology that is effective for the delivery of information such as complex navigation data. The existing control systems involve difficulties in information access and interpretation. Therefore, taking notice of the necessity for the integration of air traffic control systems, this study presents the mixed reality (MR) system, which is a new approach, that enables the control of air traffic in interactive environments. This system is provided in a form usable in actual operational environments with a head-mounted see-through display installed with a controller to enable more structured work support. In addition, since this system can be controlled first-hand by air traffic controllers, it provides a new experience through improved work efficiency and productivity.

The capability of aircraft to navigate through space and to adhere to prearranged schedules directly determines the nature of the air traffic control system and the ability of this system to keep high density traffic moving safely and expeditiously. In turn, air traffic control concepts and practices can be revolutionized by increased use of new navigation techniques. Such a profound effect on the future system can be affected with automatized airborne deadreckoning equipment with or without the use of advanced techniques such as Doppler or inertial sensing. Properly applied, these aids will help to provide a growing ability to handle the increasing traffic load and at the same time maintain for all users of the airspace a highly desirable freedom and flexibility of movement. The relationship of self-contained aids to other navigation aids, to communications, and to the other elements of the common air traffic control system is treated in this paper. Also discussed are some of the problems involved in the integration of this technique in the over-all system.

The general architecture of the US National Airspace System (NAS) is presented. Background on the overall air traffic control (ATC) system's history is given as prologue to descriptions of the major elements of the NAS Plan, the US Federal Aviation Administration's current effort to upgrade and modernize the ATC system. Technologies central to achieving the planned end-state configuration for each element are characterized in terms of their functional impact and potential benefit. Communications, navigation aids, weather support, surveillance, and maintenance systems are all undergoing significant technology upgrade. Digital processing capabilities and communications technology lead the way in permitting this modernization program to become reality. Significant consolidation efforts are yielding a much more cost-effective, responsive, and flexible ATC environment.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

This work addresses data acquisition problems associated with an improved air traffic control system. A mathematical theory of scattering which describes the multipath process is developed. From this model, the optimum signal structure required for ranging and communicating data through the multipath propagation medium is derived. It is shown that the Reed-Solomon Codes have near optimum properties for ranging and data communications. A baseline data transmission system for air traffic control is designed which will accommodate 4000 aircraft per second at the rate of 100 bits per second in a 60 by 120 mile area. The baseline system combines coding with frequency hopping as the best means of combating severe multipath interference. Several coding systems are compared and curves relating error rate to E <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">b</inf> /N <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</inf> (signal-to-noise energy per bit) for a channel characterized by Rayleigh fading are presented. This paper concludes that a ground-to-air and air-to-ground high capacity data link at a reasonable cost will be feasible for an improved air traffic control system.

Traffic congestion is one of the main problems in transportation sector and it causes a lot of drawbacks to public. The traffic light system is used to reduce the level of occurring traffic congestion. Generally, the available traffic light systems use a fixed time setting. This old traffic control system is no longer able to manage the ever-changing traffic conditions effectively and efficiently, causing a long queue of vehicles. To overcome this problem, a traffic light control system that can adapt to actual conditions of road density and can run automatically is offered. This system utilizes Google Map API as a road density data source. The result of this study is a traffic control system that can adjust the green light time duration based on the obtained density values and density trends, simulation of this adaptive system as well as simulation results analysis. A prototype of this adaptive control system was also produced in this study.

This paper proposes a new intelligent traffic control (ITC) system which is more efficient than the traffic control system currently used in the state of Kuwait.The proposed ITC system is designed as a dynamic system by using a fuzzy expert system; the fuzzy rules are applied in the visual basic and computer-based program (Excel) to run the validation process.The developed control system applied on five intersections in the grid network at four periods.The results show that the number of vehicles passing the intersection phases is increased in most phases by an average of 12.9% at the first period, 23.3% at the second period, 10.4% at the third period and by 21.2% at the fourth period.For the same periods, the phases green time is increased by an average of 9.1%, 5.8%, 9.9% and 6.3%.And the number of intersection cycles remains constant at the most time which means that the developed control system distributes the phases green time dynamically based on the traffic situation.

In this paper a framework for an airport ground traffic surveillance system based on visual information is presented. The framework is designed to improve state-of-the-art Advanced Surface Movement Guidance and Control Systems (A-SMGCS) adding an image processing module able to act as a “gap-filler” for airport zones that traditional systems fail to reliably cover due to reflections and blind spots. Results of the approach based on a set of videos is presented demonstrating that the proposed framework is a flexible and cost-effective solution for improving existing systems' performance.

The issue of improving the efficiency of the information and measurement system of automated air traffic control systems on the example of the distance measuring channel algorithm synthesis for following up the aircraft is considered. The choice of state and observation models is justified, computer simulation is performed, and the results of the studied algorithm are obtained.

Traffic congestion especially at road intersections is becoming an issue for which road traffic users contend with daily. The conventional traffic light applies a fixed logic of allocating equal “GO” time to lanes of traffic at road intersections irrespective of the density of traffic on each lane. Using the PIC18F4550 microcontroller interfaced with infrared sensors, a new traffic light control system was developed to ease the flow of traffic at a particular troubled spot in Uyo Metropolis (Abak Road, Udo Eduok, Udo Obio streets intersection) in Akwa Ibom State, Nigeria. Simulation of the proposed design was performed using the Proteus Software while implementation was carried out on a prototype. Performance evaluation of the prototype implemented showed that the 4 arrays (IR Transmitter and Receiver) of infrared sensors interfaced with the microcontroller using AND gates and strategically positioned to read the density of traffic on each lane at the intersection triggered when a vehicle comes between the transmitter and the receiver. Obtaining inputs from these sensors together with the logic from the microcontroller, a new traffic light control system was developed capable of controlling traffic based on the density of each lane of traffic. Results obtained from simulation and implementation of the design indicates that the traffic control system with the PIC18F4550 microcontroller and the infrared sensors gives a better performance compared to the conventional traffic light control system.Keywords: Road traffic density, Traffic light, Uyo metropolis, ‘+’ road intersection, Proteus