Challenge
Satellite communication test engineers need a NAV I/O (Navigational Input/Output system) to monitor large quantities of data, in real-time, from multiple sources such as; ship antennas, shore antennas, a ship simulation roll tower and communication terminals on both ship and shore. The challenge is to present this information to the test engineers in a way it could be easily viewed and recorded.
Approach
Realtime Microsystems built a brand new system with the following aspects:
Modular Client/Server Design: Client/Server architecture that separates the data from the presentation and allows the GUI to be updated without changing any of the hardware or software on the server sub-system.
Interactive Graphic User Interface: The client sub-system runs on standard PC and Windows environment user interface. The users are all currently familiar with this computing environment. The NAV I/O users will be able to control the display and recording of the data through this window.
Operating Systems: The server used the Microsoft Windows CE Operating System which allows the software to be developed in languages C++ and Visual Basic rather than obscure real-time languages.
Software: A structured software engineering process was followed and clear documentation provided. The software was developed using Microsoft C++ and Visual Basic.
Hardware: The new NAV I/O would maximize the use of commercially off the shelf (COTS) components which would lower up front engineering cost and ensure replacement parts be available in a reasonable time frame at a reasonable price.
Ellen was responsible for all project phases of the client software such as requirements, test plan, design, test procedures and the user’s guide. Paper prototypes were used early in the project lifecycle.
Results
The NAV I/O software displays Antenna and Roll Tower Angles & Attitudes via analog display, digital display, recorded data.

NAV I/O Screen
Satellite engineers can control many display and recording intervals, modes & more. Graphical display tools used: Gauges, Stripcharts (roll tower angle plotted over time). Status Bar shows what’s on & off.

save screen