Regional Jets, Digital Autopilot Research

With the develop of computer techniques, the digital autopilot system has replaced the analog system.The analog system has not been able to adapt the developmental desire of modem autopilot system function.The digital autopilot system,of which the computre is main part, has put up tremendous superiority in aspect of flight control system.The main task of this dissertation is to digitize an autopilot system installed in a certain lateral airliner.The difficulty of this task is to design and manufacture a dissimilar redundancy fault-tolerant autopilot computer. Because fault-tolerant autopilot computer is the hardcore of the digital autopilot system,the emphases of this dissertation is to investigate the dissimilar redundancy fault-tolerant computer system techniques.To tolerate faults, the techniques rely on redundant implementations, which are N-modular redundancy for building fault-tolerant hardware and N-version programming or recovery blocks method for building fault-tolerant software. The dissimilar redundancy fault-tolerant method bases on the assumption: that the different implementations use different designs and thereby contain different faults. This method will reduce the shared fault and make system with higher reliability.The system this paper has brought forward is a dissimilar redundancy fault-tolerant computer system, whose main structure used dissimilar CPUs (180486 and 180960) to build its hardware system and N-version programming to build its software system.First,this paper has discussed the hardware and software configuration of the dissimilar redundancy fault-tolerant computer system,and described how to realize this fault-tolerant system and proposed a reliability model based it.Second,it has introduced the constitute and the principium of the mode select panel which we have manufactured. Finally,it has discussed how to establish the semi-physical simulation environment for digital autopilot system.