尖楔前体飞行器FADS系统测压孔故障对算法精度的影响

NUMERICAL EFFECT OF PRESSURE PORTS FAULT IN THE FADS SYSTEM APPLIED TO FLIGHT VEHICLE WITH SHARP WEDGED FORE-BODIES

测压孔故障是嵌入式大气数据传感(flush air data sensing,FADS)系统实际工程应用中不可避免的工程问题之一,针对尖楔前体飞行器用FADS系统测压孔故障对算法精度的影响进行研究。基于人工神经网络建模技术建立了某型尖楔前体飞行器FADS系统的模型及解算方法,并分析了驻点压力对算法精度的影响。通过人为设置故障测压孔的方法对不同测压孔故障对FADS系统解算精度的影响进行了评估;最终结合实现精度需求给出了某型FADS系统在保证精度要求下的对各个测压孔的误差限需求。结果表明,驻点压力及位于迎风面的测压孔对尖楔前体类FADS系统解算精度影响显著;通过采用相邻的位于同一迎风面或背风面的测压孔替换故障测压孔能够显著降低故障对算法精度的影响;同时表明合理的冗余配置算法会显著提高FADS系统的鲁棒性,使得FADS系统适用性显著增强。

Pressure ports fault is an unavoidable engineering problem for the flush air data sensing(FADS)system.Effect of pressure ports fault on algorithm accuracy of the FADS system applied to flight vehicle with sharp wedged fore-bodies is investigated in this paper.Solving model and algorithm of the FADS system applied to the vehicle with sharp wedged fore-bodies is obtained based on the artificial neural network modeling,and the effect of stagnation pressure on solving algorithm accuracy is analyzed.Artificial failure in the pressure ports is set up to evaluate the pressure ports configuration’s effect on the solving accuracy of the FADS system.Finally,threshold error distribution for each pressure port is determined which can assure the solving accuracy level.The results show that stagnation pressure and the pressure ports located on the windward areas has great effect on the solving accuracy of the FADS system.Proper correction of the faulty inputs with near pressure port located on the same windward or leeward areas can reduce the effect of failed pressure ports on the solving accuracy.Redundancy configuration will significantly increase the robustness of the FADS system,and broaden its application field.