Extended state observer-based finite-time guidance laws on account of thruster dynamics. (September 2019)

• Record Type: Journal Article
• Authors: Duan, Meijun; Zhou, Di; Cheng, Dalin
• Is Part Of: Proceedings of the Institution of Mechanical Engineers. Volume 233:Number 12(2019)
• Page Start: 4583
• Page End: 4597
• Publication Date: 2019-09
• Subjects: Near space -- guidance law -- finite time convergence -- dynamics -- hysteresis-band switching -- extended state observer; Aeronautics -- Periodicals; Astronautics -- Periodicals; Airplanes -- Design and construction -- Periodicals; Aerospace industries -- Periodicals; 629.1
• DOI: 10.1177/0954410019827175
• Languages: English
• ISSNs: 0954-4100

Abstract

Guidance laws are designed for a near space interceptor with line-of-sight angle as input and on–off type thrust as output. The dynamics of thruster is viewed as a first-order lag with on–off working style and is integrated with the target–interceptor engagement dynamics to design bang-bang type sliding mode guidance laws. An extended state observer is designed to estimate the line-of-sight angular rate and the acceleration of target with the line-of-sight angle as a measurement. It is rigorously proved that the states of guidance system converge to a neighborhood of sliding mode in finite time and the line-of-sight angular rate converges to a neighborhood of the origin along the sliding mode in finite time under the designed guidance laws. Furthermore, in order to reduce the switching frequency of thruster, a sliding mode guidance law with hysteresis-band according to the sufficient condition for finite time convergence is proposed. Then, it is integrated with the bang-bang type sliding mode guidance law to yield a composite guidance law. Simulation results show that the extended state observer can effectively estimate the line-of-sight angular rate and the target acceleration, and the proposed sliding mode guidance laws have better performance than typical proportional guidance law.