Research On Rapid Transfer Alignment For Sins Of Tactical Guided Weapons

The world politics situation has changed from the two poles confronting each other to multiple poles, and the military strategies of the countries in possession of strong military force have greatly changed. With the development of the local world wars, the military strategies of the countries in possession of strong military force have turned their military strategic emphases from countrywide strategic defense and offense to local region defense and offense. Tactical guided weapons play an important part in war region defense and offense. In order to adapt tactical guided weapons to the characteristic of agility, levity and burst tactics, it is required that the alignment of their strapdown inertial navigation systems is rapid, accurate and robust. How to deal with the conflict between the rapidity and the accuracy of inertial navigation systems has been important topic in inertial technology field for a long time. Because tactical guided weapons are commonly launched on vehicles and in bad environments, their alignment robust performance is more important. In order to solve above problem, wavelet theory and robust filtering theory are applied to transfer alignment in this dissertation. Investigation is done in the following.Because many master inertial navigation systems on vehicles are gimbaled inertial navigation systems and don't provide angle rate, a new rapid transfer alignment approach called velocity plus attitude change matching approach is proposed. This approach direct estimates misalignment angle between master and slave inertial navigation systems and its suboptimal Kalman filter only has six state variables. Simulation shows it is very effective. The concept and approach of twice transfer alignment and thrice transfer alignment are presented. Twice rapid transfer alignment approach to the missiles carried aboard in flight, twice and thrice rapid transfer alignment approach to high-speed missiles carried on warships that are launched vertically are proposed according to the concept. All the three approaches in the first phrase employ the velocity plus attitude change matching, and perform the first time transfer alignment between master INS and slave SINS of missiles. The first time transfer alignment mainly performs azimuth alignment and primarily performs horizon alignment before missiles are launched. In the second phrase the approach employs velocity matching and performs the second time transfer alignment between GPS and SINS of missiles. For the missiles carried aboard in flight, the second time transfer alignment is carried out after the missiles are launched, and the horizon alignment is performed in the second phrase. For the high-speed missiles carried on warships that are launched vertically, the second time transfer alignment is carried out when missiles are rising and its task is to perform horizon alignment once more. The third time transfer alignment of the missiles carried on warships is carried out when the missiles are in level and straight flight, and its task is to perform azimuth alignment once more. Twice and thrice alignment approaches reduce accurate alignment time before launching the missiles.The influence of maneuver on observable degree of state variables are investigated intensively, and the approach of enhancing observable degree of the state variables in Kalman filter is proposed. Furthermore, Increasing maneuver intensity can enhance observable degree of the state variables in Kalman filter is demonstrated in theory, and several approaches of enhancing observable degree of the state variables are presented.Based on H_∞filtering theory in Krein space, H_∞filter is applied to rapid transfer alignment. The robustness of estimation accuracy of H_∞filter and Kalman filter against uncertain noise is investigated. The study result shows that within a certain range of noise uncertainty, Kalman filter has robustness against uncertain noise, and in accuracy robustness Kalman filter is superior to H_∞filter, but the estimation speed of H_∞filter is superior to Kalman filter. Based on the result, an approach to twice rapid transfer alignment based on H_∞filtering associated withKalman filtering is proposed. In the first time alignment, H_∞filter feature being taken advantage of, horizontal alignment is achieved by velocity matching. In the second time alignment, Kalman filter being used, azimuth alignment is achieved by velocity plus attitude change matching. Robust Kalman filter in Krein space is applied to rapid transfer alignment. It is showed that in the case of parameter perturbation, with the equivalent intensity of white noise and the parameters of robust Kalman filter are properly chose, the accuracy robustness of robust Kalman filter is superior to that of standard Kalman filter.Based on wavelet transform and lifting wavelet transform theory, wavelet filtering and lifting wavelet filtering are applied to rapid transfer alignment. The rapid transfer alignment approaches based on wavelet pre-filtering with batch data and lifting wavelet pre-filtering with batch data are proposed. It is showed that the proposed approaches are very effective.