Model Analysis Methods For Control Integrated Design Of Hypersonic Vehicles

Hypersonic vehicles provide great potentiality in the future aerospace and military development.The influence of multiple factors,such as the complex flight condition and special configuration with the frame-engine integrated design,makes dynamic characteristics distinctive,thereby bringing new challenges for the control system design.This paper establishes a set of modeling and performance analysis methods in consideration of the flight condition,configuration parameters and control performances,and identifies the feasible compromise design strategy integrated with the performance index of multiple constraints.As a result,the satisfactory study object is provided for the control integrated design of hypersonic vehicles.Furthermore,this paper is composed of two main contents concerning the modeling and performance analysis,and the specific work as follows:The modeling work of hypersonic vehicles aims to acquire the model database looked like the X-43 A configuration,and then to deduce the surrogate model suitable for the control integrated design.This work is divided into three parts.The first part is the geometric parametric modeling of hypersonic vehicles using the CST method to identify the geometric shape.The second part is to build a model database of hypersonic vehicles with a given flight range.To this end,the aerodynamic force,moment and thrust can be obtained using the engineering estimation and panel methods in relation to the established configuration.The third part is to build the surrogate model using two methods based on data fitting and mechanism derivation for the model database,which taking into account the accuracy and efficiency.Furthermore,the actual physical meanings of the surrogate model are explained to provide the theoretical basis for the following model analysis work,which is in consideration of the flight condition,configuration parameters.The performance analysis work is to find out a compromise design strategy of control integrated design with the multi-constraints by synthetically considering the relationship between the flight condition,shape parameters and control performances.First,the control-related performances are analyzed,including aerodynamic derivatives,unstable pole zero,robustness,bandwidth,null controllable region,overload,flight path angle delay and instantaneous center of rotation;Then,the multi-constraints under different flight conditions are found out,and the flight range satisfied with the compromise performances is obtained accordingly.Finally,the performance analysis is conducted for the hypersonic vehicle model based on the varying parameters,and the trade-off design scheme is proposed to meet multiple constraints after considering the effects on the model performance with the change of the centre of gravity,mass,elevon position and elevon surface.As a result,the feasible integrated design results are acquired;wherein double iterative optimization of flight conditions and design parameters are used.These works provide the satisfactory modeling and performance analysis methods for the control integrated design of hypersonic vehicles.