Abstract
The predicted impact point (PIP) of hypersonic interception changes continually; therefore the midcourse guidance law must have the ability of online trajectory optimization. In this paper, an online trajectory generation algorithm is designed based on neighboring optimal control (NOC) theory and improved indirect Radau pseudospectral method (IRPM). A trajectory optimization model is designed according to the features of operations in near space. Two-point boundary value problems (TPBVPs) are obtained based on NOC theory. The second-order linear form of transversality conditions is deduced backward to express the modifications of terminal states, costates, and flight time in terms of current state errors and terminal constraints modifications. By treating the current states and the optimal costates modifications as initial constraints and perturbations, the feedback control variables are obtained based on improved IRPM and nominal trajectory information. The simulation results show that when the changes of terminal constraints are not relatively large, this method can generate a modified trajectory effectively with high precision of terminal modifications. The design concept can provide a reference for the design of the online trajectory generation system of hypersonic vehicles.
Highlights
After decades of development, hypersonic technology has made a lot of progress [1,2,3]
Because the nonpropulsive phase is more difficult for trajectory adjustment, the terminal predicted impact point (PIP) is modified at the initial time of the nonpropulsive phase with altitude increasing 2 km and flight path angle increasing 5 deg
neighboring optimal control (NOC) represents the modified trajectory generated based on NOC theory and the improved indirect Radau pseudospectral method (IRPM) solving algorithm designed in this paper
Summary
Hypersonic technology has made a lot of progress [1,2,3]. Hypersonic vehicles will be used in military as precision strike weapons or platforms in the near future. The demand on the research of advanced intercept and defense technology is urgent. In allusion to the high speed and large maneuverability of hypersonic weapons, the interceptor should adopt the compound guidance strategy to improve the success rate of interception. From the end of program control flight to the target acquisition of terminal guidance, the interceptor spends most of the time flying in the midcourse guidance. The flight performance of midcourse guidance determines the overall performance
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
