Approved as a Wallops control center backup system, the Wallops Ship Surveillance Software is a day-of-launch risk analysis tool for spaceport activities. The system calculates impact probabilities and displays ship locations relative to boundary lines. It enables rapid analysis of possible flight paths to preclude the need to cancel launches and allow execution of launches in a timely manner. Its design is based on low-cost, large-customer-base elements including personal computers, the Windows operating system, C/C++ object-oriented software, and network interfaces. In conformance with the NASA software safety standard, the system is designed to ensure that it does not falsely report a safe-for-launch condition. To improve the current ship surveillance method, the system is designed to prevent delay of launch under a safe-for-launch condition.
A single workstation is designated the controller of the official ship information and the official risk analysis. Copies of this information are shared with other networked workstations. The program design is divided into five subsystems areas:
- Communication Link – threads that control the networking of workstations;
- Contact List – a thread that controls a list of protected item (ocean vessel) information;
- Hazard List – threads that control a list of hazardous item (debris) information and associated risk calculation information;
- Display – threads that control operator inputs and screen display outputs; and
- Archive – a thread that controls archive file read and write access.
Currently, most of the hazard list thread and parts of other threads are being reused as part of a new ship surveillance system, under the SureTrak project.
This work was done by Donna C. Smith of Goddard Space Flight Center. GSC-15623-1