William R. Murray
The Blackboard Instructional Planner is a blackboard-based dynamic planner for intelligent tutoring systems. It generates a sequence of lesson plans customized to a student’s background, and adaptively replan, to handle student requests and unexpected changes to the student model or time remaining. The planner is designed to be generic to tutors that teach troubleshooting for complex physical devices. It controls the Lower Hoist Tutor, a prototype tutor for the Mark-45 naval gun mount. This tutor teaches troubleshooting of the lower hoist, a complex hydraulic-electronic-mechanical assembly of the Mark-45 The tutor implementation demonstrates the planner’s operation and means of integration. This research contributes to an understanding of dynamic instructional planners, planner-controlled tutors, and ITS control architectures. The planner implementation shows precisely how a blackboard architecture can be used to realize a dynamic instructional planner. Although experimental, the tutor implementation demonstrates how such a planner can be embedded in an intelligent tutoring system and what the respective roles of the different components of a pianner-controlled tutor are. Finally, the analysis of the planner’s use of the blackboard architecture clarifies requirements for control architectures in intelligent tutoring systems and trade-offs made in choosing alternatives.