Adaptive segmentation multistage linear spectrum generalized standard control missdistance reentry guidance method

Abstract

The invention discloses an adaptive segmentation multistage linear spectrum generalized standard control missdistance reentry guidance method. The guidance method is applied to a high-lift-drag-ratio reentry aircraft and can satisfy multiple terminal constraints and process constraints. The method combines basic ideas of nonlinear model prediction control, a multistage linear pseudo spectrum method and calculus of variations, is greatly different from a Yu method in that a processing object is reduced-order nonlinear reentry dynamics taking a coupling effect into consideration, and also takes terminal heights and trajectory inclination angle constraints into consideration apart from considering a terminal position requirement and a roll angle requirement.

Description

technical field [0001] The invention relates to the field of aeronautical flight, in particular to an adaptive segmented multi-segment linear pseudo-spectrum generalized standard control miss amount reentry guidance method. Background technique [0002] As we all know, the re-entry aircraft needs to withstand the harsh re-entry environment during the re-entry flight phase, and the re-entry guidance system—providing guidance instructions to guide the aircraft to fly to the target safely and accurately is very important for the re-entry flight. With the successful flight of Apollo spacecraft and space shuttle, the research of reentry guidance algorithm has made great progress. [0003] Although many types of guidance algorithms exist, the most famous guidance algorithm is the space shuttle guidance law, which is the basis for all tracking guidance algorithms. The space shuttle re-entry aircraft guidance law is mainly divided into two parts, one part is to plan a drag accelera...

AI Technical Summary

Problems solved by technology

Based on the assumption of quasi-equilibrium gliding, Shen and Lu developed a fast online planning algorithm to generate a feasible trajectory that satisfies the path constraints. However, the existing predictive correction algorithms use the traditional course error angle corridor to control the lateral trajectory. , high lift-to-drag ratio re-entry vehicle, this method will lead to a large lateral error, therefore, Shen studied the lateral guidance control strategy using the terminal lateral distance as the corridor, and improved the lateral guidance accuracy of medium lift-to-drag ratio aircraft

[0005] It should be pointed out that the time consumption of these predictive correction algorithms will increase exponentially with the increase of the number of control parameters, because the gradient information used to update the control parameters is obtained by using the secant method of numerical integration, Therefore, in order to reduce the complexity of the algorithm and enhance the robustness of the algorithm, these predictive correction algorithms usually only consider one or two control parameters, which will only guarantee fewer terminal constraints

In addition, these algorithms use the threshold corridor restriction strategy to reduce the heading angle error. For aircraft with high lift-to-drag ratio, this will not only greatly limit the lateral maneuverability of the aircraft, but also bring large lateral errors and more roll Number of reversals

Images