978-1-4673-1900-3/12/$31.00 ©2012 IEEE L5-1

IEMID: A MOBILE MULTI-INFORMATION DISPLAY FOR SURVEILLANCE DATA

Mohamed Mahmoud, Johnathan Pesce, Embry-Riddle Aeronautical University, Daytona Beach, FL

Abstract This paper describes the mobile application that

has been developed at the Embry-Riddle Aeronautical University (ERAU) Next-Generation ERAU Applied Research (NEAR) Laboratory. ERAU Multi Information Display (EMID) displays surveillance information based on Automatic dependency Surveillance Broadcast (ADS-B) standards used in FAA Next-Generation Air-Traffic Management (ATM). The initial version of the EMID was developed at the request of the ERAU flight department, for the purpose of monitoring the university fleet of over 75 ADS-B equipped aircraft. The later version of the EMID had incorporated additional functionalities to provide a platform for test and evaluation of new concepts in ATM and National Airspace (NAS) Usage.

One of the advantages of the EMID is the use of SWIM (System Wide Information Management) like architecture, which allows the display of ADS-B and TIS-B aircraft position data received from SWIM-like surveillance services. ADS-B and TIS-B aircraft are represented by symbols that have optional data blocks capable of displaying altitude, speed, heading, and latitude/longitude information. EMID uses a different color coding scheme to distinguish between the commercial (blue) and general aviation (green) traffic. This color coding scheme has proven to make the product more user friendly, and reduce the overall workload of the user in identifying potential en-route conflicts. A mobile device version of the EMID called iEMID, has been developed using iOS [1] which can be deployed on iPhone and iPad devices.

iEMID is a mobile Geographical Information System (GIS) based application capable of displaying geospatial referenced data. It supports pan and zoom and allows the user the capability to turn on/off different data layers. iEMID is capable of displaying high fidelity ESRI shape files of airspace volumes and airport layouts for precise tracking of aircraft while taxiing on the airport surface. This paper will concentrate on the overall functionality of the EMID and iEMID, and discuss some of the advantages and

disadvantages of the product. We will also discuss the supporting infrastructure that is needed to allow system functionality. For example, the ADS-B surveillance service hosted at the NEAR lab that manages several ground receivers.

Background Embry-Riddle pioneered the incorporating and

testing of ADS-B in its aircraft during the FAA’s SAFE Flight 21 program. The flight-training fleet at its campuses in Daytona Beach, FL and Prescott, AZ, are fully equipped with glass cockpits and ADS-B In and Out capability. In an effort to support the ERAU flight department’s daily operation in managing flight training and ensuring safety, the researchers at the NEAR laboratory were tasked to design and implement an application capable of displaying surveillance data on a desktop and eventually, a portable device. To accomplish this task it was also necessary to implement the infrastructure to collect and deliver the ADS-B data to the applications. The university has been collecting and archiving ADS-B and TIS-B data since 1999 when it started receiving it from the FAA’s Safe Flight 21 program. When the Safe Flight 21 program ended, ERAU procured their own Ground Based Receivers (GBR) in order to maintain coverage of our Daytona Beach, FL and Prescott, AZ campus fleets. Since the creation of the first EMID application, new uses for the application have come to light for student flight training analysis and review, flight safety monitoring and FAA NextGen related research activities. The ADS-B data archive has been used for data mining in research and scenario building for simulations.

EMID Application EMID desktop application was built using the

OpenMap [3] open source Geographic Information System (GIS) based API. OpenMap allows rapid prototyping and integration of geospatial information.

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Figure 1. EMID Displaying Training Practice Areas

The application is capable of displaying geospatial referenced data, such as ESRI shape files, weather data, or Geo Tiff files. It supports pan and zoom and allows the user to turn data layers on and off. Each data layer renders specific geospatial data. For example, ADS-B surveillance data can be rendered on one layer while another layer renders airspace information. This layering approach allows the integration, but separation, of different data sources that lead to a very rich display.

EMID is capable of displaying high fidelity ESRI shape files of airspace volumes and aircraft layouts allowing for the precise tracking of aircraft while taxiing. Not only is the application capable of consuming standard geospatial data, it can also consume nonstandard data such as Jeppesen Total Airspace and Airport Modeler (TAAM) polygon files. TAAM polygon files can be used to render special airspace or airport layouts that are not available in standard formats. An example is ERAU’s student flight training practice areas shown in red on Figure 1. EMID also displays ADS-B and TIS-B aircraft position data received from SWIM-like surveillance services. ADS-B and TIS-B aircraft are represented by symbols that have optional data blocks capable of displaying altitude, speed, heading, and latitude/longitude information. For ease of visualization, TIS-B aircraft are displayed in cyan, and ADS-B aircraft are displayed in blue when airborne and brown when on the ground. This color coding scheme has proven to make the product more

user friendly, and reduce the overall workload of the user in identifying potential en-route conflicts. Additionally, a speed vector can be rendered for both ADS-B and TIS-B aircraft to show the predicted heading and distance traveled in the next 30 seconds.

Figure 2. EMID Showing Airport Operator View

The application was deployed to ERAU flight department to be used in tracking their fleet of ADS-B equipped aircraft, managing fleet aircraft distribution per practice area, as a playback tool for student pilot briefings and for safety incident investigation. It has also been used as a part of an integrated Unmanned Aircraft System (UAS) used to train pilots in a UAS pilot degree program at ERAU. The virtual-reality air system consists of a flight simulator with an ADS-B adaptor that extracts the vehicle state information and generates ADS-B messages which then get published to a simulation server. A separate simulation layer was added to the EMID display to receive data from the simulation server to be rendered. This approach allows the integration of real-time ADS-B traffic with simulated UAV aircraft for a more realistic training.

ERAU Surveillance Infrastructure The university has been collecting and archiving

ADS-B and TIS-B data since 1999 when it started receiving it from the FAA’s Safe Flight 21 program. When the FAA’s Safe Flight 21 program ended, ERAU procured their own Ground Based Receivers (GBR) in order to maintain coverage of our Daytona

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Beach, FL and Prescott, AZ campus fleets. The university owns and operates one receiver at each campus for the General Aviation Universal Access Transceiver (UAT) ADS-B equipped aircraft (978 MHz) and one 1090ES receiver at the Daytona Beach campus for ModeS Extended Squitter ADS-B equipped aircraft (1090MHz). The UAT receivers have a range of approximately 150 miles and the 1090ES receiver has a range of approximately 300 miles. The range varies with terrain, aircraft transmission power and aircraft altitude and orientation as the signal is line-of-site.

The ADS-B and TIS-B data produced by the FAA’s Safe Flight 21 program and ADS-B data produced by ERAU’s GBRs is formatted using the FAA’s ASTERIX[4] Category 33 Version 1 specification. ASTERIX is the EUROCONTROL standard for the exchange of surveillance related data. It was developed with multi-national participation to facilitate the exchange of surveillance data in an international context. The CAT033 specification was defined by the FAA for its ground based ADS-B and TIS-B data distribution. When the FAA ended the Safe Flight 21 program and outsourced the ADS-B ground infrastructure to ITT, the FAA and ITT worked together to define the CAT033 Version 2 and now Version 3 used today by the National Airspace System (NAS).

Version 1 and version 3 ASTERIX CAT033 data is fundamentally different in the way the data source is identified. In both versions, the source of the CAT033 data is identified by a pair of one byte System Area Code (SAC) and System Identification Code (SIC) values. In the version 1specification the Ground Based Transceiver (GBT) received the aircraft broadcasted data has a designated SAC/SIC pair it places in each CAT033 message to identify itself as the source. In this case, the SAC refers to the region of the world, and the SIC is used to identify individual systems like a transceiver, sensor or fusion processor. In the version 3 specification a SAC/SIC pair is assigned to each service volume defined. The SAC now refers to the region of the world and the NAS domain it serves, such as EnRoute Class A or Terminal Class B airspace. The SIC is now a unique identifier for the service volume or composite traffic volume, such as Pheonix Terminal or Jacksonville Center. A Service Volume can collect data from one or more GBTs.

ASTERIX CAT023 also has a version 1 and version 3 specification that are used to communicate the service’s status, which includes the health of the GBTs, fusion trackers and/or Service Volumes. CAT023 is used to monitor the data sources and alert operators if they can’t be relied upon or are in need of service.

ERAU maintains a production enterprise environment, Figure 3, to collect, store, and distribute the live ADS-B data streaming in from the GBRs as well as other sources that include simulators and external data feeds along with the CAT023 service status messages. In the event that there is an issue with a service volume or equipment, the collection server can alert an administrator of the problem via email or some other service.

Figure 3. Surveillance Infrastructure

The EMID and other applications also make use of the data playback service to select previously recorded data for playback. There are many reasons why data may need to be played back. These range from a student and instructor wanting to review performance during a flight, to a safety officer wanting to investigate an incident. With the new iEMID application students will soon be able to share their flights with parents and friends. The university and our clients also use this data archive for the creation of scenarios for human-in-the-loop and fast-time simulations for ATM, airspace and airport studies.

Data

Store

Collection

Server

Playback

Service

Distribution

Service

PR UAT DB UAT DB 1090ES

User

Application

External

Systems

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iEMID Application With the successful development and

deployment of the EMID application, a mobile version called iEMID, Figure 4, was developed for Apple iOS. The iEMID is a universal application capable of running on different iOS devices, including iPhone, iPad and iPod, with iOS 4.0 and above.

Figure 4. iEMID Running On An iPAD

User tap gesture recognition is enabled to allow the user to tap close to an aircraft object and trigger that aircraft’s extended data block to be displayed. Commercial 1090ES ADS-B equipped aircraft are rendered in blue while GA UAT ADS-B equipped aircraft are shown in green, Figure 5.

Figure 5. iEMID Running On An iPhone

iEMID automatically detects the network connectivity of either the Wi-Fi or Cellular network and connects to the SWIM-like surveillance data service. In the event of a loss of connection, the application will automatically reconnect using the available network.

The application uses the Google map API as the underlying mapping system. A separate layer is added to render the surveillance model data using iOS core graphics. Using core graphics rather than using iOS MKMapView annotation and overlay API allowed maximum flexibility in creating displayed objects and a smaller byte size per surveillance object model.

The application was designed to be modular following the Model View Controller (MVC) design pattern, Figure 6. This design pattern allows the separation of the input logic and the business domain logic of the application from the User Interface (UI) logic, which in turn allows reusability of the same model for different views and independent development, testing and maintenance of each.

Controller

ModelView

Update

NotifyUpdate

User action

Figure 6. MVC Design Pattern

The View displays information contained in the model and handles user interaction.

The Controller acts as a mediator to instruct the View about when and what to display.

The Model contains and manages application data

The application model is contains several components as follows; a connection handler that is responsible for handling connections to the data service, an ADS-B data parser for extracting surveillance information, an ADS-B data handler to manage adding and removal of surveillance data and

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sending notifications whenever a new surveillance data map is available, Figure 7.

View

Controller

Model

Connection Handler

ADS-BParser

ADS-B data Handler

MapController

MKMapView

SurveillanceView

Notify

User Tap

ObjectFinder

Figure 7. iEMID MVC

Decoupling is used to separate the received ADS-B data format from the surveillance data used by the application. This separation reduces the application’s dependency on specific data formats, which allows the application to be able to consume different sources of data with minimum effort.

Human Factors The iEMID user interface was designed using

Apple’s iOS Human Interface Guidelines (HIG). The HIG describes the guidelines and principles that help iOS developers design an exceptional user interface and user experience. Using the HIG, feedback from ERAU’s human factors department and beta testers from ERAU’s flight department, the following points where taken into consideration when designing the UI.

1. The size of the rendered aircraft object is changed based on the zoom level of the map, Figure 8.

2. The rendered aircraft color was changed from what was used in the EMID to blue for commercial aircraft and green for GA aircraft in iEMID.

3. Full use of the display real estate for the MapView with minimum use of logos.

Figure 8. iEMID Aircraft Size at Two Zooms

iEMID Performance and Testing The iEMID application was executed under

several test cases to verify proper functionality and that performance was maintained.

Connectivity: The mobile device executing the application was positioned at such a location and then moved in such a way as to trigger the event of switching from Cellular network to Wi-Fi and vise versa. Correct releasing of resources in the event of a loss of connection and the successful re-establishment of connection to the services were observed.

Capacity: The application was connected to the TAAM ADS-B gateway and a TAAM simulation was run that published simulated ADS-B data for 1500 aircraft. The update rate was almost identical to a real life ADS-B update rate. The iEMID application maintained its responsiveness to gesture and handled iOS memory warnings without crashing while conducted using Wi-Fi.

Power consumption: The application was executed for an hour long test on an Apple iPad where the battery indicator showed a loss of around 2% of battery life for every

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45-60 minutes of runtime with no other applications running in the background.

NextGen Applications The EMID application has been deployed at the

FAA’s Florida NextGen Test-Bed (FTB), located at the Daytona Beach International Airport, in support of multiple NextGen demonstration tasks over the past few years.

The EMID application is deployed at the FTB in three roles:

1. Its first role is as a fleet monitor for a Fixed Based Operator (FTB), in this case ERAU flight operations. It is deployed alongside the ERAU ETA dispatching client to monitor movement of the fleet on the airport surface and during flight.

2. Its second role is as an airport operations and tower surface situational awareness tool. Daytona Beach International Airport does not have an ASDE-X system so an EMID demonstrates a way to fill that hole since almost all local traffic are ERAU’s ADS-B equipped aircraft.

3. Its third role acts as a Cockpit Avionics Display in a NextGen cockpit. The EMID Cockpit Avionics Display provides a visual interface for displaying geographic borders and waterways, ATC sectors, MOAs, SUA

and warning areas. It was enhanced with a demonstration prototype Datalink Service capability for an FAA Surface Flight Data Object Demonstration. For the demonstration, when the pseudo pilot signs onto the Datalink Service, the Datalink Service updates the Flight Data Object with the flight’s datalink status. Uplinked clearance notifications appear on the EMID for the pilot to acknowledge. EMID automatically performs a hardware acknowledgement to the Datalink Service that the clearance data has arrived at the aircraft and displays that fact to the pilot by highlighting the clearance in blue. The pilot then manually selects the clearance information to acknowledge that it was received and viewed. The pilots selection transmits acknowledgement to the Datalink Service and turns the indication to green. When the Datalink Service uplinks a Pre-Departure Clearance or Landing Clearance, the display renders the uplinked Surface Flight Data Object (SFDO) surface trajectory on the airport surface diagram for the pilot to follow, Figure 9. For ease of visualization, TIS-B aircraft are displayed in cyan, and ADS-B aircraft are displayed in blue when airborne and brown when on the ground.

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Figure 9. EMID Avionics Display of Issued Clearances and Departure Surface Trajectory

Conclusion Embry-Riddle pioneered the incorporating and

testing of ADS-B in its flight-training fleet at its campuses in Daytona Beach, FL and Prescott, AZ. Each aircraft are fully equipped with glass cockpits and ADS-B In and Out capability. In support of the university flight department’s daily operation in managing flight training and ensuring safety, the researchers at the NEAR laboratory successfully designed and implemented the EMID and iEMID applications, which are capable of displaying surveillance data on a desktop and a portable device respectfully. Along with these applications, the NEAR lab implemented the infrastructure to collect and deliver the ADS-B data to the applications using SWIM-like services. The university has been collecting and archiving ADS-B data since 1999. ERAU now has their own GBRs in order to maintain coverage of our Daytona Beach, FL and Prescott, AZ campus fleets. Since the creation of EMID, new uses for the application have come to light for student flight training analysis and review,

flight safety monitoring and FAA NextGen related research activities. The ADS-B data archive continues to be used for data mining in research and scenario building for simulations.

The biggest hurdle in creating the iEMID application was learning Objective C and the iOS APIs. With that behind us, we are already planning future uses for mobile devices to bring SWIM services into the NextGen cockpit.

References [1] http://www.apple.com/

[2] http://www.gis.com/

[3] http://openmap.bbn.com/

[4] http://www.eurocontrol.int/asterix

2012 Integrated Communications Navigation

and Surveillance (ICNS) Conference April 24-26, 2012