Research On Automatic Reading System Of Aircraft Angle Of Attack Instrument

Despite the large number of powerful electronic instruments,the traditional mechanical pointer instrument still exists as a backup instrument exists in most aircraft cockpits.At present,whether during the operation of the aircraft or during the ground maintenance phase,the way of reading the pointer instrument is achieved by manual visual reading.There are many questions,such as low precision of manual visual reading and slow speed.These factors will lay a lot of hidden dangers to the safe operation of the aircraft.In addition,with the development of science and technology,machine vision technology has been gradually introduced into various fields,and many industries have developed image recognition devices that can automatically recognize meter readings.Therefore to study the reading recognition of the instruments in the cockpit of the aircraft has great significance for the automation and intelligent development of aircraft driving.The research of the automatic reading system of the AOA instrument in the cockpit of an aircraft is introduced in this dissertation.The AOA instrument is taken as the object of recognition with the digital image processing technology to realize the automatic identification.The research is mainly consisted of three parts: image pre-processing,image processing of the AOA instrument image,recognition of instrument reading.Hardware design,test and error analysis of the systems are implement.In the section of pre-processing,image graying and noise reduction are implemented.In the section of image processing,the threshold segmentation method,edge extraction method and connected conponent labeling method are used to segment image and locate the dial area to obtain a clear image of the dial area.In the section of recognition of instrument reading,the meter pointer and the reference datum are extracted,and the cosine theorem is used to realize automatic identification of reading of instrument.In the hardware platform of the image recognition system,the composition of the hardware platform of the image recognition system is introduced.In the section of test and error analysis of the automatic reading system of AOA instrument,the automatic reading system of AOA instrument system is tested under different lightingconditions.The relative error of the recognition result is calculated and the cause of the deviation is analyzed.The recognition result shows that,under the condition that the lighting conditions do not change significantly,automatic reading system of AOA instrument can assist the manual reading of the meter.