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C-4.2 Command and Command Procedure Definition

Figure C-3 depicts the data flow for the Define Commands and Command Procedures process. Data originates in the Command Requirements and Vehicle Command Word Structure data stores, which define source information needed to generate specific data items needed to support Commanding. This information would include formatting rules, contingency conditions, verification methods, and fault recovery methods. The generated products include the Constraint DB, Command Info DB, Command Eval DB, and Command Anomaly Resolution KB data stores. The Constraint DB data store contains the constraint rules for each SV command, i.e., the conditions that must be valid before the command can be released to the SV. The Command Info DB data store contains information about each command, including formatting rules for generating the command load, command decode information, etc. The Command Eval DB data store contains the rules or procedures for evaluating and verifying command execution. The Command Anomaly Resolution KB data store contains knowledge bases needed for automated detection and resolution of commanding-related anomalies. The Command Pool data storecontains command elements, such as single commands, block commands, and memory uploads, which are represented as sequences of bits that can be executed by the SV. The Timeline data store contains a description of the overall pass plan, and the command activities within the plan. This information is used by Generate Command Plan to link executable elements to command plan steps and store them in the Command Processing Product data store. The following describes the processes identified in Figure C-3.

Generate Command DBs - This function builds a number of databases used to support command plan construction, evaluation, and anomaly resolution. It inputs the vehicle-specific command word structure provided by the contractor. This will likely be in some standard database format. In addition, this function inputs vehicle specific command requirements, such as the constraints that must be present for release of a particular command or conditions that would indicate its successful execution. This function outputs the Constraint DB, the Command Info DB, the Command Evaluation DB, and the Command Anomaly Resolution KB. The command pool is a temporary storage area for load ready command elements.

Generate Command Loads - This function generates command loads that can be executed by an SV. Processing is initiated by the Timeline data store, which also indicates commands for which command loads are needed. This function inputs the command format definitions, which are formatting rules for each command. This function may also process satellite software and database memory uploads. The output of this function is the command load, called the command element, that goes to the command pool.

Generate Command Plan - This function generates the command plan, the sequence of commands issued during a pass to accomplish some task. It uses the pass plan and associated information from the Timeline data store to determine the sequence of command steps and conditional steps needed to achieve the goal of the pass plan. Generate Command Plan may optionally input a Recommended Corrective Action, which is a predefined command plan from Telemetry or from Determine Command Performance. It also inputs command elements, which are executable commands from the command pool. The output of this function are the command plans, which are a series of steps and decisions linked to the executable command elements.

Figure C-3. Define Commands and Command Procedures data flow diagram.