Application of Multivariate Nonlinear Fitting in Multi Component Test of Solid Rocket

Motor vector thrust is synthesized by six components measured through using multicomponent test stand.However,mutual interference presents in flexible assemblies of each sensor installed on multi-component test stand.To improve measurement accuracy,multivariate nonlinear fitting method is adopted to reduce the coupling error of flexible assemblies.Take horizontal six-component test stand as an example,this paper introduces the cause of thrust measurement error with using six-component test stand,as well as the theoretical basis of multivariate nonlinear fitting method.By using this method,the coefficient of each component is calculated during thrust calibration,and coupling formula is established.The main thrust of motor is synthesized through multivariate nonlinear decoupling.The test result is consistent with theoretical estimates.