6.6.2 Location reports

The Blue Report Act in Figure 5 is invoked every time a location report is posted in the EA Manager database, which can happen several times each second. However, the Watchman agent filters location reports that are not of interest to the EA Manager (e.g., for entities irrelevant to the plan of the EA owner, or because there is no change from the last report), and updates the representation of the current situation in the EA. The Blue Report Act is specific to the SUO domain, but our framework requires a similar Act to be written for each type of input that is to be actively monitored. For example, there is a similar UV-Robotics Act that responds to state updates (see Section 7.4). These Acts are written using the Act-Editor [46], a tool for graphically editing procedural knowledge (Acts) with an intuitive user interface.

This Act begins by invoking a domain-specific specialized reasoner to check for fratricide risk, which may have the side effect of giving an alert (using the API function issue-alert). The specialized reasoner can easily be replaced by better fratricide detection algorithms in the future. Next, the Blue Report Act checks whether the current plan has any expectations for this unit, and if so, it calls the API function check-expected-location to compare the current location to the expected location, again posting an alert if appropriate. Finally, the report fact is removed from the database.

Responding to a fused sensor track indicating adversarial activity is controlled by a similar Red Report Act, which compares adversarial activity to plan expectations. Instead of analyzing fratricide risk, the Red Report Act invokes a reasoner for evaluating adversarial threats. As described in Section 6.7, this involves updating a threat envelope for each friendly unit.