Design And Realization Of Real-time Online Vibration Measurement System Of Piston Aero Engine For UAV

The aero-engine is hailed as the jewel in the industrial crown and is the highest indicator of a country's overall manufacturing technology.For a long time,China's aeroengine design,manufacturing and testing technologies have been strictly blocked by the West,making this field the biggest shortcoming that has slowed the development of China's cutting-edge defense technology and the construction of an aviation power.Based on the research content of the aero-engine front end of output shaft dynamic balance detection in the major scientific and technological project of Sichuan Province-"Threetype engine repair technology(19ZDZX0057)",this paper develops a multi-channel realtime online monitoring system with high-precision for detecting engine front end of output shaft vibration.This work is supposed to make a reference contribution to the progress of China's aero-engine technology in vibration detection.Aiming at the vibration fault characteristics of aero-engines,the vibration types and output shaft front end mechanish,bearing and gear are studied.Because the weight,significance and measurability of vibration faults produced by different parts of aeroengine are different,the critical speed and vibration intensity of front end of output shaft vibration faults are selected as the monitoring objects of the developed vibration measurement system through the comparative study of various fault characteristic parameters.Through the analysis of the characteristics of the object to be tested and the detection method,the overall scheme of the vibration measurement system is designed,and the specific design and implementation method based on the overall scheme are detailed in the following.According to the characteristics of real-time online and remote transmission of the designed vibration measurement system,VxWorks real-time embedded operating system is used in the software design to preprocess and transfer the vibration digital signal to the file system based on Nandflash and Norflash.After the ECC test,the data is sent to the debugging terminal through Ethernet for displaying,realizing the dynamic monitoring and fault warning of front end of output shaft vibration state.On the other hand,a vibration measurement system is successfully designed based on the characteristics of multi-channel synchronization and high-precision measurement.As the core signal processing unit is "arm + CPLD",the signal acquisition front-end is X-Y-Z three-channel synchronous vibration sensor,and the general computer is used as the data monitoring display terminal.In order to verify whether the function and performance of the vibration measurement system designed in this paper can meet the expected targets,the x-y-z three-channel synchronous vibration test of the front end of output shaft system(output shaft)is carried out for a small piston aero-engine equipped with a new UAV.The failure warning is realized by analyzing the relevant critical speed and vibration intensity parameters under deceleration,constant speed and acceleration early warningAmong the creative achievements in this paper,the Ethernet communication system based on the improved data frame and sensor digital signal conditioning logic for X-Y-Z three-channel synchronous sampling is the major achievement.The results above use Ethernet instead of the traditional Fieldbus to realize the remote measurement,and use three-way synchronous data acquisition to enhance the reliability of the classical vibration measurement,providing a platform for the design of a new remote aero-engine health monitor.