Research And Implementation Of Avionics Relay System Real-time Scheduling Method

In the process of integrated verification of avionics system design schemes for large civil airliners,due to the large number of avionics components or hardware-in-the-loop simulators,complex signal cross-links,and often located in different physical spaces,real-time data interaction between system components becomes the key problem to be solved.This article designs a set of avionics relay system,which can realize the interconnection and communication of long-distance avionics equipment with effective communication distance up to kilometers,and adapt to a variety of avionics data with short delay time and high-speeding forwarding.First of all,the design goals are formulated through requirements analysis and the overall architecture of the avionics relay system is designed.Secondly,the real-time scheduling method of terminal collection incentive software development is studied,combining the priority allocation idea of the deadline monotonic scheduling algorithm and the priority-based preemptive scheduling algorithm,and it is applied to the VxWorks operating system application development process to propose an avionics relay task preemptive scheduling method with deadline monotonic priority assignment.This method is used to assign priority to the terminal task set of the avionics relay system,and the schedulability analysis theory corresponding to the method is used to determine that the task set is schedulable,and then the method is used to schedule the task set.The scheduling logic analysis of this scheduling design also shows that the task set is schedulable.Then,the reflective memory network technology is studied to get a specific reflective memory allocation scheme,and the design and implementation of the configuration management system software is completed,and the design and implementation of the acquisition incentive software is completed based on the scheduling design.Finally,the avionics relay system test and verification experiments are performed according to the design goals.The accuracy and delay time of the data forwarded by the avionics relay system are mainly tested,and the data centralized monitoring of the avionics relay system is verified.The experimental results show that the avionics relay system operates stably and reliably,and can remotely forward 4 types of avionics data at the same time.Each type of data can achieve multiple concurrent channel forwarding,and the amount of forwarded data meets the requirements.The maximum time of delay of the system is in the order of millisecond level,which meets the real-time requirements of system design.The centralized monitoring of the data forwarded by the system shows that it meets the requirements of centralized monitoring.