Research On Onboard CMCF Simulation System Based On AFDX Network

As a key part of modern civil aircraft R&D, avionics system's characteristics including its intelligence and modular are getting more and more obvious, resulting in the integration of avionics system more complex. Therefore, the CMS(central maintenance system) as the core of avionics maintenance system gradually becomes a research hotspot of modern civil aircraft. As an important part of CMS, CMCF(Central Maintenance Computing Function) module is mainly used for monitoring the operation of avionics systems on real-time, and processing failure information which are generated during the flight. Therefore, studying CMCF is significant.Onboard CMCF simulation system was designed for functional simulation of CMCF based on AFDX avionics bus. Data interaction between the CMCF module and the aircraft member system was researched. The simulation module can send data via AFDX network to each aircraft member system, and it can also summarize and report failures which are generated by aircraft member system.First of all, by getting familiar with AFDX data bus characteristics and studying ARINC664-7 standards, the working principle of CMCF was analyzed, the design principles and the communication configuration and architecture of onboard CMCF simulation were summarized. On this basis, the CMCF simulation system was modular designed, a system-level configuration was created, and a detailed design of the simulation system was finally proposed.Then, according to the design, AFDX board card and system communication interface was selected to build the simulation platform. Meanwhile, the simulation software was developed, including simulation system information modification function module, aircraft status information functional module, fault reporting module, self-test functional module and so on. A normal communication between simulation system and aircraft systems was implemented.Finally, a system testing to onboard CMCF simulation system was completed, and the simulation system can satisfy the design requirements by receiving and sending data for testing. The design was able to provide technical support to CMCC research, and have some practical value.