Research On The Layout Of Monitoring Network For On-Orbital Debris Impact Source Localization

With the developing space exploration,the number of on-orbital debris is increasing.On-orbital debris pose a tremendous threat to the safety of spacecraft.The apperceive system based on acoustic emission(AE)technique has the ability to monitor the debris impact in real time,and can also localize the impact,which is conductive to in-time reaction.While the anisotropic propagation caused by the characters like stiffened,bulges and so on,makes the variation propagation velocity in each direction.It can hardly get accurate localization with traditional AE technique,acquiring the location of on-orbital impact source is one of the most important problems needed to be solved.Addressing this issue,a new AE localization technique and a layout method of AE source localization monitoring network are proposed.The main research of this article are as follows:The area localization based on the nearest neighbors takes the arrival time difference as the type labels,and is not affected to the propagation velocity variation,so it can be used in the AE source localization on complex structures.This work compares the obtention of arrive time with different threshold times,and the deviation caused by the threshold selection,also the affection it causes in the localization algorithm,build the mathematic equation of the arrival time deviation and the threshold times.According this equation,using weight coefficients to decrease the deviation affection.The validation shows that,with these coefficients,the localization accuracy will increases in varying degree.Then this work proposes the effect function of each sensor by experiments,meshes the sensor network monitoring area,and selects the field value as the monitoring capacity measurement of a sensor network,and obtains the relation of the field value and the localization accuracy.Using this result,an optimal method of sensor network layout is proposed,this article also analyses the influences caused by the sensor number variation,localization accuracy requirement and the sensor failure.In this work,the type labels of artificial datum is generated by air gun,and ends up with a satisfying result supplying for the hypervelocity impact localization,which validates the feasibility of using artificial datum in the research of hypervelocity impact source localization.Finally,to validate the sensor layout method,partial network is embedded on a small plate with the same material as the manned pressurized cabin.It shows that it is feasible in an enclosed sensor area.