The Design Of Fault Detecting Platform Of Onboard Avionics Devices Based On ARINC429 Bus

ARINC429 bus is a digital information transmission system(DITS), which is an onboard bus norm formulated and presented by American Aeronautical Radio Inc(ARINC) in 1977. The bus is widely used in the civil aviation field, which effectively simplifies the interconnection between aircraft equipments, and improves data transmission efficiency and reliability of the aviation system, and also reduces the occupied payload of interconnect cables. Since announcement, because of its superior performance, ARINC429 has been soon applied to the field of civil aviation by countries around the world. Now, as one of the most widely used aviation data bus, ARINC429 bus plays an increasingly prominent role. So, research on ARJNC429 bus is still significant.At present, most avionics communication systems in civil aircraft around the world apply ARINC429 bus to networking and communicate. It is a widely used data transformat in civil airplane, so in the process of maintenance and fault detection to avionics electronic equipments in most active service civil airplanes, it is necessary to transform a variety of signals in the format of ARINC429. Although many avionics electronic equipment manufacturers provide kinds of specialized detectors, they are targeted, and most are tailored equipments. So, it is not easy to detect fault rapidly and exactly to maintainers in so many avionics electronic equipments networked by 429 bus. In order to achieve this goal, to break the technological monopoly by foreign product and to change the situation of high price, it is of vital practical value to design a fault detection platform based on ARINC429 bus, which can simplify test procedures of onboard devices, and is significant to promote aviation in our country.The paper aims to design a fault detection platform, which uses ARINC429 bus as its data interface and PC as operation interface, and to complete test, fault detection and analysis to onboard electronic devices. The key part of the design is the detector of ARINC429 bus. The detector receives messages from onboard electronic devices through ARINC429 bus and monitors operating states of ARINC429 bus. Further, the detector can send specific data to the bus and simulate some kind of working condition of avionic equipments, and complete fault analysis through bus data. Before writing, this article refers to a large number of domestic and foreign materials about ARINC429 bus. In consideration of the facts that testing systems of detectors are complicated, big and expensive, the paper researches the bus protocols and design ideas, and presents a solution to a fault detection platform in avionic equipments.The design is composed of hardware and software. The former consists three parts-USB interface circuit, USB-ARINC429 interface circuit and ARINC429 level switching circuit. The later is composed of upper computer application program, USB drive program, USB bottom firmware program and FPGA program of slave computer. Finally, in order to verify the correctness of the design, the paper builds a test platform to finish debugging and analysis of the basic functions and performance of the system. The test results indicate that the design performs stably with good data transfer capability, and reaches the design goals and meets the requirements of practical applications. At last, pointing out the disadvantages of the design, the paper brings out the goals and direction in later work.