1 Airspace Management Decision Tool Validating the Behavior and Structure of Software Design Kerin Thornton ENPM 643 System Validation and Verification Fall 20052Table of Contents Introduction.................................................................................................................3 Problem Statement...................................................................................................3 Assumptions............................................................................................................3 Airport Schematic....................................................................................................4 Flow of Events.........................................................................................................5 Goals, Scenarios, and Use Cases..................................................................................6 Initial Use Case Diagram.........................................................................................7 Use Case Text and Activity Diagrams......................................................................8 Use Case 1. Input Data ...........................................................................................8 Use Case 2. Issue Request.......................................................................................9 Use Case 3. Data Processing.................................................................................10 Use Case 4. Issue Order........................................................................................11 Generation of Requirements ......................................................................................12 High Level Requirements ......................................................................................12 Requirements Traceability .....................................................................................13 System Structure and System Behavior......................................................................17 High Level Structure..............................................................................................17 System Models ......................................................................................................18 Structural Design of Program Code........................................................................23 System Validation and Verification ...........................................................................24 Labeled Transition System Analyzer......................................................................25 Conclusion ................................................................................................................31 Appendix...................................................................................................................32 MATLAB Code.....................................................................................................32 MATLAB Output ..................................................................................................34 LTSA Code ...........................................................................................................36 MATLAB Validation with LTSA—50 iterations ...................................................37 References.................................................................................................................413 Introduction Problem Statement Even at small airports, air traffic controllers must maintain a constant awareness of dynamic situations. With aircraft continuously changing locations, altitudes, and airspeeds, the controller must have a precise idea of exactly where each plane is and an idea of where each is going in order to safely and efficiently control the flow of air traffic. Any misinterpretation of a given situation may lead to a wrong decision, which has the potential for disaster. This intense workload and the demands for 100% of attention 100% of the time can affect the human decision-making processes. The scope of this project is to create a model-based program which air traffic controllers at small airports may use to track aircraft positions and to issue orders to the pilot accordingly, essentially automating the decision-making process. Consider the case of a shift-change in an air traffic control tower. With a tool such as this one, the outgoing controller has entered into the program the locations of all aircraft currently under his or her control. When the incoming controller inherits these aircraft, all he or she has to do is enter the next incoming pilot request into the program, which outputs appropriate action in accordance with the request. Assuming the controller issues orders according to this output, the program is updated to reflect the new current situation. This paper follows the development of this decision-making tool, from the generation and mapping of requirements, to the UML diagramming the sequences of events, to the generation of the program code, and finally to the verification and validation of the decision support tool. Assumptions The scope of this project will assume the following conditions: 1. The airspace immediately surrounding the airport’s holding pattern is of an unlimited capacity. This is where pilots make the request to enter the holding pattern upon approach to land. 2. Only one aircraft may be in the holding pattern at any given time. 3. Only one aircraft may be on the runway at a given time (to land or to take off). 4. The airport owns two taxiways. An aircraft may taxi to the gate at the same time another aircraft is taxiing to the runway. 5. Only one aircraft may be at the gate ay a given time. 6. Once an aircraft has taken off, it has immediately cleared the airspace and is no longer under tower control. 7. The air traffic control tower may only receive one request at a time. This is enforced by the communications equipment in the tower and on board the aircraft.48. Incoming pilot requests reach the controller on a first-come, first-serve basis. 9. The controller may issue an order to a pilot who has not made a request. 10. Once an order has been issued to a pilot, the action is carried out instantaneously. Airport Schematic This airport may be described by the drawing below. At any given time there is: • An unlimited number of aircraft in the surrounding airspace • No more than one aircraft in the holding pattern • No