Inertia altitude channel damping Kalman filtering method based on atmosphere assistance

Abstract

The invention discloses an inertia altitude channel damping Kalman filtering method based on atmosphere assistance. The method comprises the following steps that firstly, an atmosphere data system pressure altitude error model in the moving process of an unmanned helicopter is established; then, based on the pressure altitude error model and a traditional inertia / atmosphere damping loop, a state equation and a measuring equation of a six-state damping Kalman filter including pressure altitude errors of an atmosphere data system and sensor errors of an inertia navigation system are established; finally, inertia / atmosphere navigation system damping Kalman filtering is carried out on the altitude error and the vertical speed error generated in the flying process of the unmanned helicopter, and a combined navigation system navigation result obtained after damping Kalman filtering is obtained. By means of the inertia altitude channel damping Kalman filtering method based on atmosphere assistance, tracking and compensation for atmosphere altitude measuring errors can be achieved in the flying process of the unmanned helicopter so as to improve the altitude precision in the atmosphere-assisted inertia navigation altitude channel, and the method is suitable for engineering application.

Description

technical field [0001] The invention relates to an inertial altitude channel damping Kalman filter method based on atmospheric assistance for an unmanned helicopter, and belongs to the technical field of altitude measurement of inertial / atmospheric navigation systems. Background technique [0002] Unmanned helicopter is a kind of unmanned aerial vehicle with power and flexible control. A variety of airborne equipment can perform multiple tasks to achieve repeated long-endurance flights. Unmanned helicopters can fly at ultra-low altitudes to avoid the detection and tracking of enemy radars. They have strong battlefield adaptability and can complete many tasks that fixed-wing aircraft cannot complete. military needs. [0003] Flight altitude is an important flight parameter of unmanned helicopters, and it is indispensable information for unmanned helicopters to achieve normal and safe driving, accurate navigation and control, effective reconnaissance and attack. The vertica...

AI Technical Summary

Problems solved by technology

The vertical position (height) can be obtained by the double time integration of the acceleration measured in the vertical direction, but the double integration of the vertical acceleration is unstable, and the acceleration deviation can cause the calculated height to increase exponentially. Therefore, the inertial navigation system depends on the acceleration Integrating the measured values ​​to obtain a height estimate is an unstable system

In order to provide a more stable inertial navigation system, external references such as barometric altimeters are used alone or in combination, but barometric altimeters have poor measurement accuracy at low altitudes and are easily affected by weather changes and gusts, resulting in inaccurate altitude measurements

[0004] At present, the inertial / atmospheric height damping method based on classical control theory is based on the two information of atmospheric height and inertial height to complement each other, so as to obtain height information with no divergence of height error and better dynamic performance, but it cannot completely solve the randomness of the atmosphere in essence. The influence of errors, the current research on atmospheric height is basically only in the research of second-order damping and third-order damping, and there are few in-depth studies on damping system theory and improvement research

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