The angular velocity estimation principal of α-β-γ filter based on high sampling rate

In order to get angular velocity of stabilization servo mechanism from angular position sensors, α-β-γ filter based on high sampling rate was established, the principle of steady and transient tracking filter differential were proved. With the hypothesis of constant acceleration, three-dimensional Kalman filter was simplified; α-β-γ filter and its angular velocity transfer function were predigested. Combing with optimum parameters, the effect of α and sample rate on filter nature frequency were evaluated. According to the requirements of stabilization platform, the frequency characteristics of angular velocity transfer function were analyzed, and the filter parameters were designed. The results show that when the spectrum of input signal was lower than 6rad/s, parameters α was 0.02, and sampling period were 0.08ms and 0.1ms respectively, the filter can realize differential exactly, when the spectrum was 9rad/s, the precision was no less than 1.1%, the phase leading of angular position was no less than 70°, the natural frequency should be higher than the cut-off frequency of stabilization platform was two or three times. In the engineering of electro-optical stabilization servo mechanism, α-β-γ filter has properties of tracking differential, and reached the requirement of platform angular velocity estimation. Also it is one of the effective methods to get angular velocity from angular position sensors.