Browsing by Author "Madani, Irfan"

Now showing 1 - 7 of 7
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    Development of a new method for ATFCM based on trajectory-based operations
    (SAGE, 2017-09-03) Gatsinzi, Dany; Saez Nieto, Francisco Javier; Madani, Irfan
    This paper discusses a possibility to evolve the current Air Traffic Flow and Capacity Management towards a more proactive approach. This new method focuses on reducing the expected probability of air traffic control intervention based on “hot spot” identification and mitigation at strategic level by applying subliminal changes on the times of arrival at the crossing or merging points (junctions). The concept is fully aligned with the trajectory-based operation principles. The approach assumes that the changes on the times of arrival only demand small speed changes from the involved aircraft. In this study, the hot spots are defined as clusters of aircraft expected to arrive to the junctions. Two aircraft are said to be in the same cluster if their proximity and closure rate are below a given threshold. Some exercises are proposed and solved by applying this method. The obtained results show its ability to remove the potential conflicts by applying simple linear programming. This approach seeks to change the current capacity limiting factor, established by the number of aircraft occupying simultaneously each sector, to another parameter where the level of traffic complexity, flowing towards junctions, is identified and mitigated at strategic level. The speed changes, used as the control variable and computed before or during the flight, are designed to provide an adjustment on aircraft’s required time of arrival at the junctions in order to have a de-randomised and well-behaved (conflict free) traffic. This will enable improvements in airspace capacity/ safety binomial. It is recognised that this measure alone is unable to produce a conflict free airspace, and then other collaborative and coordinated actions, such as adjusting and swapping departing times at the departing airports (before the aircraft are taking off), offsetting some flights from nominal route, and allowing multi-agent separation management (while they are in flight) should be applied together with this method.
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    ECAC use case of optimised pre-tactical time of arrival adjustments to reduce probability of separation infringements
    (Elsevier, 2018-07-19) Gatsinzi, Dany; Saez Nieto, Francisco Javier; Madani, Irfan
    Currently, a maximum allowable number of aircraft (A/C) entering and or within a sector for a given period is fixed. Anytime this threshold is reached, involved A/C are regulated by Air Traffic Flow and Capacity Management (ATFCM) to maintain an acceptable Air Traffic Controllers’ (ATCOs’) workload. This threshold is determined regardless of particular expected air traffic complexity, which may result from potential conflicts inherently in A/C’s flight plans that may greatly affect the ATCOs’ workload. This paper proposes a new ATFCM Demand and Capacity Balancing (DCB) methodology, applied to mitigate potential conflicts between A/C’s trajectories at pre-flight level, in order to reduce the current ATCO’s workload attributed to Separation Management (SM) interventions. This purpose is achieved through minor adjustments on A/C’s Times of Arrival (TOAs) at conflicted en-route junctions. The adjustments of A/C’s TOAs are implemented through minor changes on A/C’s speed profile, applied before and after each conflicted junction, while maintaining each A/C’s departure and Targeted Time of Arrival(TTA) at destination. The paper postulates that these TOA adjustments could be easily transformed into pre-tactical ATFCM DCB measures, assuming that ATFCM will issue Reference Business Trajectories (RBTs) containing time constraints at junctions, introduced to reduce the probability of conflicts. A case study of European Civil Aviation Conference (ECAC) air traffic network using real flight plan data is presented to show the validity of the methodology.
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    Hot spot identification and mitigation at strategic level by subliminal changes in aircraft time of arrival at junction
    (Eurocontrol, 2016-11-30) Gatsinzi, Dany; Saez Nieto, Francisco Javier; Madani, Irfan
    This paper presents some results obtained when applying a different criterion in Air Traffic Flow and Capacity Management (ATFCM) measures. The approach is based on reducing the probability of controller’s reactive interventions by "hot spot" identification and mitigation at strategic level, by applying subliminal changes on the aircraft’s Times of Arrival (TOA) at the crossing or merging points (junctions). The concept of this strategy is fully aligned with the Trajectory Based Operation (TBO) principles. It is assumed that the changes on the times of arrival only demand very small speed changes to the involved aircraft (A/C). In this assessment, hot spots are established by identifying groups of closely spaced A/C arriving at a junction. A hot spot isolates the set of A/C involved in multiple conflicts, close in their times of arrival at the junction, violating the minimum required “safe” time separation at the junction. The minimum safe time separation is established based on a chosen threshold for the probability of collision obtained by considering the different sources of uncertainties in the aircraft’s time of arrival at junction. Some exercises are proposed and solved by applying this method. The obtained results show its ability to remove the conflicts by applying simple linear optimization programming tool. The effect of this method on the aircraft’s operating costs is also analyzed. This approach also seeks to change the current capacity-limiting factor, established by the number of aircraft occupying simultaneously each sector, to another parameter where the level of traffic complexity, flowing towards junctions, will be identified and mitigated at strategic level.
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    Improving the operating efficiency of the more electric aircraft concept through optimised flight procedures
    (Springer, 2018-09-22) Seresinhe, Ravinka; Lawson, Craig;; Madani, Irfan
    The increasing awareness of the environmental risks and costs due to the growing demand in aviation has prompted both academic and industrial research into short-term and long-term technologies which could help address the challenges. Among these, the more electric aircraft has been identified as a key design concept which would make aircraft more environmentally friendly and cost effective in the long run. Moreover, the notion of free-flight and optimised trajectories has been identified as a key operational concept which would help curb the environmental effects of aircraft as well as reduce overall costs. The research in this paper presents a methodology in which these two concepts can be coupled to study the benefits of more electric aircraft (MEA) flying optimised trajectories. A wide range of issues from aircraft performance, engine performance, airframe systems operation, power off-take penalties, emission modelling, optimisation algorithms and optimisation frameworks has been addressed throughout the study. The case study is based on a popular short haul flight between London Heathrow and Amsterdam Schiphol. The culmination of the study establishes the advantage of the MEA over conventional aircraft and also addresses the enhanced approach to the classical aircraft trajectory optimisation problem. The study shows that the operation procedures to achieve a minimum fuel burn are significantly different for a conventional aircraft and MEA. Trajectory optimisation reduced the fuel burn by 17.4% for the conventional aircraft and 12.2% for the more electric compared to the respective baseline cases. Within the constraints of the study, the minimum fuel burn trajectory for the MEA consumed 9.9% less fuel than the minimum fuel burn trajectory for the conventional aircraft.
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    Obstacle detection with ultrasonic sensors and signal analysis metrics
    (Elsevier, 2018-02-03) Gibbs, Gerard; Jia, Huamin; Madani, Irfan
    One of the basic tasks for autonomous flight with aerial vehicles (drones) is the detection of obstacles within its flight environment. As the technology develops and becomes more robust, drones will become part of the toolkit to aid maintenance repair and operation (MRO) and ground personnel at airports. Currently laser technology is the primary means for obstacle detection as it provides high resolution and long range. The high intensity laser beam can result in temporary blindness for pilots when the beam targets the windscreen of aircraft on the ground or on final approach within the vicinity of the airport. An alternative is ultrasonic sensor technology, but this suffers from poor angular resolution. In this paper we present a solution using time-of-flight (TOF) data from ultrasonic sensors. This system uses a single commercial 40 kHz combined transmitter/ receiver which returns the distance to the nearest obstacle in its field of view, +/- 30 degrees given the speed of sound in air at ambient temperature. Two sonar receivers located either side of the transmitter / receiver are mounted on a horizontal rotating shaft. Rotation of this shaft allows for separate sonar observations at regular intervals which cover the field of view of the transmitter / receiver. To reduce the sampling frequency an envelope detector is used prior to the analogue-digital-conversion for each of the sonar channels. A scalar Kalman filter for each channel reduces the effects of signal noise by providing real time filtering (Drongelen, 2017a). Four signal metrics are used to determine the location of the obstacle in the sensors field of view: 1. Maximum (Peak) frequency 2. Cross correlation of raw data and PSD 3. Power Spectral Density 4. Energy Spectral Density Results obtained in an actual indoor environment are presented to support the validity of the proposed algorithm.
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    Safety assessment methods for avionics software system
    (2017-11) Mao, Jiawen; Jia, Huamin; Madani, Irfan
    Nowadays, the avionics software has been becoming more and more critical for both civil and military aircraft. However, the software may become crazy sometimes and may cause the catastrophic result if any failure in software. Therefore, the software safety assessment is not only crucial to the specific software, but also for the system and aircraft. Although there are some industry standards as guidelines for development of software system, applications of these standards to practical software systems are still challenged and hard to operate in practice. This thesis tries to solve this problem. After analyses and summaries of the system safety assessment process and existing software safety assessment process in different fields, research wants to propose the systematic and comprehensive software safety assessment process and method for avionics software. The thesis presents the research process, and proposes one suitable avionics software safety assessment process. Meanwhile, thesis uses a real functional block in flight management system as a case study, and then conducts the software safety requirement assessment based on the proposed software safety assessment method. After analysis the result of case study, this proposed software safety assessment process and methods can quickly and correctly identify the software design errors. So, this analysis can use to prove the feasibility and validity of this proposed software safety assessment process and methods, which will help engineers modify every software design errors at the early stage in order to guarantee the software safety.
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    Traffic avoidance and separation system
    (IEEE, 2017-12-04) Katta, Balaji Raman; Madani, Irfan
    Aircraft need to be separated from other aircraft by either a minimum vertical distance of 1000ft or by a minimum horizontal distance of 5NM to avoid mid-air collisions. Traffic Alert and Collision Avoidance System (TCAS) work well as a tactical safety backups to avoid collision, but cannot perform separation assurance. This paper presents the design aspects of system that would predict separation infringement and provide flight crew with necessary guidance for maintaining separation. This paper discusses formulation of system function based on ADS-B, mathematical models, simulation and results. A system model has been implemented in MATLAB and various encounters with different speed ratios at various conflict angles has been fed as input to system model with a goal of avoidance and recovery to original waypoint. Both Heading and Speed maneuvers are evaluated and results are presented. The required strength of resolution maneuver as a function of conflict geometry is studied and automatic maneuver selection function is implemented in system model and maneuver selection function is evaluated with discussion of results.