SCL Ground Software
Spacecraft Command Language (SCL) combines a real-time Expert System and Command Interpreter, which enable both event-driven (using rules) and time-based procedural (using scripts) operation. The SCL Real-Time Engine (RTE) provides a multi-tasking executive for testbeds, simulations, control centers and a variety of industrial control solutions. Additionally, scripts and rules developed on a workstation can be deployed to embedded systems providing a symmetrical architecture between workstations and embedded systems.
Using a message oriented service called the SCL Software Message Bus, SCL is modular and loosely coupled which increases flexibility for scalability and the addition of mission unique software applications. The full-featured scripting language is designed for ease-of-use and does not require a software professional to develop scripts and rules. It also allows engineers, technicians and test conductors to author the SCL logic and exercise the system and the end-unit article.
The SCL system has provided 24/7 service for the several spacecraft missions. The FUSE Mission Operations Center was built around SCL and operated continuously for more than 8.5 years. The TacSat-2 Mission Operations Center used SCL for the one year Pathfinder mission for the Operational Responsive Space Office (ORS).
The SCL Ground software system includes:
SCL Real Time Engine
Rule Based Expert System
Scheduling Manager
Command Execution Manager
SCL Compiler
Script & Rule Compiler
Command Interpreter
SCL Viewer
Shared memory database
SCL Software Message Bus
SML - Command/Telemetry Definitions and Packet Formatter
Packet Decommutation
Packet Generation
For information on the SCL Flight Software click here.