Boundary Conditions

1. Boundary Conditions 15-413 Samuel Chong Repair Team STARS Project Carnegie Mellon University 11 November 1999 2 Sticky Technology for Augmented Reality Systems

2. Subsystem Breakdown • Augmented Reality • Authoring • Inspection • Modeling • Repair • Workflow Sticky Technology for Augmented Reality Systems

3. Subsystem Dependencies Sticky Technology for Augmented Reality Systems

4. Initialization • Augmented Reality • UI service provider • No data required, no other systems required • Expects widgets from Modeling, Inspection, and Repair • Authoring • Access into the workflow database must be available • An initialization data file must be available • Paper document sources must be available Sticky Technology for Augmented Reality Systems

5. Initialization (cont) • Inspection • Augmented Reality must provide its services • Modeling • Augmented Reality must provide its services • Workflow database must be available for data on the airplane Sticky Technology for Augmented Reality Systems

6. Initialization (cont) • Repair • Inspection should provide its visual UI for workorder and sticky navigation • Workflow database should provide documents such as workorders and IETMs • Workflow • Server requires a user data file for authorization purposes • Client has no initialization dependencies Sticky Technology for Augmented Reality Systems

7. Termination • Workflow • Database should be highly available; i.e. termination is not a normal occurrence • Client has no restrictions on termination • Workflow is unaffected by the termination of other systems • Authoring • System is only required during creation and modification of digital documents, and will terminate once that is done • Termination does not affect other subsystems Sticky Technology for Augmented Reality Systems

8. Termination • Augmented Reality • Should terminate only when PEDD is not being used • If terminated, other subsystems running on the PEDD will no longer receive input events except through speech • Repair • Should terminate once the repair is done • If terminated, other subsystems running on the PEDD can no longer be speech-controlled Sticky Technology for Augmented Reality Systems

9. Termination • Modeling • Will terminate when maintenance is over • Does not affect other subsystems when terminated • Inspection • Will terminate once maintenance is over • Data must be saved to Workflow database • Termination will render Repair subsystem non-functional Sticky Technology for Augmented Reality Systems

10. Failure Overview • Communications failure • Likely to be a common problem because of the environment • Wireless communication, if it is not available, should be covered by a wired alternative • Data loss • True robust error recovery is beyond the scope of this phase of the project • Reinitialization of each system is the easy solution for crash recovery Sticky Technology for Augmented Reality Systems

11. Failure • Workflow • Notifications • Other subsystems will have to wait until communications are restored to retrieve data • Augmented Reality • No external communications requirements • No persistent data to back up Sticky Technology for Augmented Reality Systems

12. Failure • Authoring • If workflow is unavailable, no submissions are possible • Version control can provide limited protection from data loss • Modeling • Relies somewhat on the Workflow database for some necessary information • No persistent data to back up Sticky Technology for Augmented Reality Systems

13. Failure • Inspection and Repair • If Workflow database is down, no data can be retrieved or submitted • All persistent data is stored in Workflow database Sticky Technology for Augmented Reality Systems