A path network model for predicting performance of a loosely coupled DRE system in the GeoSurv II UAV project

The on-board computer system of the GeoSury II Unmanned Aerial Vehicle (UAV) is a small-scale loosely coupled distributed real-time and embedded (DRE) system. Ideally, a loosely coupled DRE system is combined with applications, a publish/subscribe middleware, a real-time operating system and time deterministic network hardware. Even though many performance modeling and analysis approaches are available, there is still a need of a simple model to help application developers predict the performance of the GeoSury II UAV computer system.;This dissertation addresses the need for the development of an analytic modeling approach named Path Network (PN) modeling, which can be used to predict whether a loosely coupled DRE environment is appropriate for the GeoSury II UAV applications. The visual notation of the PN model is designed, and the temporal parameters of the PN model are characterized. The environment overheads are broken down into several pieces for performance prediction. The algorithm for calculating the performance is described in detail. The prediction results are compared with the measurement results of a UAV experimental system to validate PN modeling. Even though the test-bed is not an ideal loosely coupled DRE environment, the results of the case study still indicate that PN modeling provides a simple and easy way for application developers to predict the performance of the on-board, loosely coupled DRE system of the GeoSury II UAV.