The Research On The Method Of Angle Of Attack Measuring Based On Four-Quad Pressure Sensors

The angle of attack of missiles and rockets is the token to forecast whether the control system loses control of the missiles and drop out halfway of ballistic trajectory, it's also the main technical characteristics of flight stability of missiles and rockets. Angle of attack measuring has very important meaning.This paper uses the design theory of Flush Airdate Sensing System for reference, and puts forward an angle of attack measuring system which is suitable for the measurement of missiles and rockets. The system uses the piezoresistive pressure sensors to measure the pressure on the skin of missiles and rockets, and realizes the measurement of angle of attack directly. The paper presents the structure, principle and arithmetic model detailedly, and brings forward the computing methods of air-parameter, mainly including the arithmetic of angle of attack and angle of sideslip, the arithmetic of calibration parameter and the iterative arithmetic of impact pressure and free stream static pressure in the condition of rolling pills and irrotional pills. At the same time the modified arithmetic of angle of attack and angle of sideslip is put forward. This dissertation also puts forward a new arithmetic of angle of attack, using the generalized regression nerve network to obtain the angle of attack, and this arithmetic is certificated correct by emulation result. In addition, a method of multi-calibration is applied to eliminate the differences between sensors used in the measurement system by wind tunnel data, and the paper validates the new arithmetic of angle of attack and calibrates the calibration parameter through wind tunnel data.At last, a hardware measurement system of angle of attack is designed, and an airdate collection, control and data-processing flat roof is established using VC++, which makes the whole collection system easily controlled.