Onboard guidance system design for reusable launch vehicles in the terminal area energy management phase. (February 2018)

• Record Type: Journal Article
• Authors: Mu, Lingxia; Yu, Xiang; Zhang, Y.M.; Li, Ping; Wang, Xinmin
• Is Part Of: Acta astronautica. Volume 143(2018)
• Page Start: 62
• Page End: 75
• Publication Date: 2018-02
• Subjects: Terminal area energy management (TAEM) -- Guidance system -- Trajectory planning -- Ground-track predictor -- Reusable launch vehicle (RLV); Astronautics -- Periodicals; Outer space -- Exploration -- Periodicals; Astronautics; Periodicals; 629.405
• DOI: 10.1016/j.actaastro.2017.10.027
• Languages: English
• ISSNs: 0094-5765

Abstract

Abstract: A terminal area energy management (TAEM) guidance system for an unpowered reusable launch vehicle (RLV) is proposed in this paper. The mathematical model representing the RLV gliding motion is provided, followed by a transformation of extracting the required dynamics for reference profile generation. Reference longitudinal profiles are conceived based on the capability of maximum dive and maximum glide that a RLV can perform. The trajectory is obtained by iterating the motion equations at each node of altitude, where the angle of attack and the flight-path angle are regarded as regulating variables. An onboard ground-track predictor is constructed to generate the current range-to-go and lateral commands online. Although the longitudinal profile generation requires pre-processing using the RLV aerodynamics, the ground-track prediction can be executed online. This makes the guidance scheme adaptable to abnormal conditions. Finally, the guidance law is designed to track the reference commands. Numerical simulations demonstrate that the proposed guidance scheme is capable of guiding the RLV to the desired touchdown conditions. Highlights: An onboard TAEM guidance system is designed for an unpowered RLV. Constrained longitudinal profiles are generated by an iteration algorithm. Longitudinal and lateral motions are integrated by an onboard management scheme. Trajectory tracking laws are developed considering in-flight situations. The effectiveness of the guidance system is verified by several simulation tests.