Study on Error Measurement Method for Actuator Frequency Characteristic Test System

System error measurement is key step in actuator frequency characteristic test and practical system error measurement methods must be studied to provide qualified results for system error compensation. Two error measurement methods (swept sine and FFT: fast Fourier transform) are explored, a strong anti-jamming frequency characteristic algorithm is perfected for swept sine and digital smoothing is introduced for improving accuracy of FFT. Numerical examples verified accuracy and robustness of swept sine and validity of FFT. These methods were applied to measure system error in missile actuator test system, the experiments showed that swept sine method could gain smooth and stable results and FFT method could achieve rather close results with swept sine. This study is part of general test system of some missile and provides valid technology analysis and reliable measurement results of system error for its actuator test.