Modeling of Avionics Systems using JGrafchart and TrueTime

Sammanfattning: The first part of the thesis aims to investigate the applicability of JGrafchart and its associated Model of Computation(MoC) for describing sequential control in aircraft primary power distribution systems. The motivation behind this is the need for better modeling tools and in particular support for separation between nominal control and fault handling. Also, as system complexity increases, better structuring capabilities are required. The application for this part of the thesis is a typical primary power distribution system in a medium-sized aircraft, and JGrafchart is used as substitute for Stateflow for the sequential parts of the controller. Simulations were run to determine whether JGrafchart is suitable for these types of systems, and if it provided any additional value compared to Stateflow. The second part focus around a different tool (TrueTime) to help assess the impact of embedded architecture on control performance. Today it is common for systems to be distributed over multi-tasking kernel nodes, which communicate on different networks. In these systems the nodes compete for the shared resources (The CPU and bandwidth) and the distribution of bandwidth is determined by the network protocol. Since the shared resources are limited in terms of bandwidth different kinds of delays arise, such as transmission delays and back-off times. The delays might lower the control performance significantly, which is why it is important to identify them early in the development process, preferably at the design stage. In the thesis, TrueTime is extended to support Avionics Full Duplex Switched Ehternet(AFDX) and applied to a typical aircraft electric power system.