Method for obtaining coupling dynamic response of momentum wheel and spacecraft structure

The invention provides a method for obtaining coupling dynamic response of a momentum wheel and a spacecraft structure. According to the method, firstly, a transfer matrix of the spacecraft structure is measured; secondly, modeling is conducted on the momentum wheel according to a given spring-mass-block model, and a transfer matrix of the momentum wheel is obtained; thirdly, according to a displacement coordination equation and a force coordination equation, a system coupling analysis matrix is obtained through calculation; finally, a time domain pulse response function of a system is obtained through an inverse Fourier transform, and a system time domain response is obtained through a Duhamei integral formula. The transfer matrix of the spacecraft structure is obtained through test measurement, and the precision is higher than that of a transfer matrix obtained through traditional finite element modeling. The structural dynamics characteristic of the momentum wheel is depicted through the spring-mass-block model, calculation is easy and convenient, and a model is easy to correct through test data. The system transfer matrix obtained through the method accurately reflects the changes of the mode characteristic of the momentum wheel and influence of the momentum wheel on a partial structure of a spacecraft after the momentum wheel is arranged on the spacecraft.