# Disturbance-Observer-Based Robust H∞ Switching Tracking Control for Near Space Interceptor

• Guo, Chao (School of Automation, Northwestern Polytechnical University) ;
• Liang, Xiao-Geng (Luoyang Optoelectro Technology Development Center)
• Received : 2014.01.03
• Accepted : 2014.05.08
• Published : 2014.06.30

#### Abstract

A novel robust $H_{\infty}$ switching tracking control design method with disturbance observer is proposed for the near space interceptor (NSI) with aerodynamic fins and reaction jets. Initially, the flight envelop of the NSI is divided into small subregions, and a slow-fast loop polytopic linear parameter varying (LPV) model is proposed, to approximate the nonlinear dynamic of the NSI, based on the Jacobian linearization and Tensor-Product (T-P) model transformation approach. A disturbance observer is then constructed, to estimate the modeled disturbance. Subsequently, based on the descriptor system method, a robust switching controller is developed, to ensure that the closed-loop descriptor system is stable with a desired $H_{\infty}$ disturbance attenuation level. Furthermore, the outcome of the proposed switching tracking control problem is formulated as a set of linear matrix inequalities (LMIs). Finally, simulation results demonstrate the effectiveness of the proposed design method.

#### References

1. Wang, W., "Near-space vehicle-borne SAR with reflector antenna for high-resolution and wide-swath remote sensing", IEEE Transactions on Geoscience and Remote Sensing, Vol. 50, No. 2, 2012, pp. 338-348. https://doi.org/10.1109/TGRS.2011.2158224
2. Davis, M., and White, J., "X-43A flight-test-determined aerodynamic force and moment characteristics at Mach 7.0", Journal of Spacecraft and Rockets, Vol. 45, No. 3, 2008, pp. 472-484. https://doi.org/10.2514/1.30413
3. Xing, L., Zhang, K., and Chen, W., et al., "Optimal control and output feedback considerations for missile with blended aero-fin and lateral impulsive thrust", Chinese Journal of Aeronautics, Vol. 23, No. 4, 2010, pp. 401-408. https://doi.org/10.1016/S1000-9361(09)60234-X
4. Zhou, D., and Shao, C., "Dynamics and autopilot design for endoatmospheric interceptors with dual control systems", Aerospace Science and Technology, Vol. 13, No. 6, 2009, pp. 291-300. https://doi.org/10.1016/j.ast.2009.05.004
5. Thukral, A., and Innocenti, M., "A sliding mode missile pitch autopilot synthesis for high angle of attack maneuvering", IEEE Transactions on Control Systems Technology, Vol. 6, No. 3, 1998, pp. 359-371. https://doi.org/10.1109/87.668037
6. Zhao, M., Wei, M., and He, Q., "Research on method of lateral jet and aerodynamic fins compound control based on finite time stability and backstepping approach", Journal of Astronautics, Vol. 31, No. 9, 2010, pp. 2157-2164.
7. Li, Z., Wei, M., and Zhou, D., et al, Technology of lateral thrust and aerodynamics blended control for anti-air missile, China Astronautic Publishing House, Beijing, 2012.
8. Petres, Z., Polytopic decomposition of linear parameter varying models by tensor-product model transformation, Budapest University of Technology and Economics, Budapest, 2006.
9. Wu, F., and Cai, X., "Switching fault-tolerant control of a flexible air-breathing hypersonic vehicle", Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering, Vol. 227, No. 1, 2013, pp. 24-38. https://doi.org/10.1177/0959651812453914
10. Zhou, K., Doyle, J., and Glover, K., Robust and Optimal Control, Prentice Hall, Englewood Cliffs, New Jersey, 1995.
11. Yu, S., Yu, X., and Shirinzadeh, B., et al., "Continuous finite-time control for robotic manipulators with terminal sliding mode", Automatica, Vol. 41, No. 11, 2005, pp. 1957-1964. https://doi.org/10.1016/j.automatica.2005.07.001
12. Chen, W., "Disturbance observer based control for nonlinear systems", IEEE/ASME Transactions on Mechatronics, Vol. 9, No. 4, 2004, pp. 706-710. https://doi.org/10.1109/TMECH.2004.839034
13. Wei, X., and Guo, L., "Composite disturbanceobserver- based control and $H{\infty}$ control for complex continuous models", International Journal of Robust and Nonlinear Control, Vol. 20, No. 1, 2010, pp. 106-118. https://doi.org/10.1002/rnc.1425
14. Yang, J., Li, S., and Sun, C., et al., "Nonlineardisturbance- observer-based robust flight control for airbreathing hypersonic vehicles", IEEE Transactions on Aerospace and Electronic Systems, Vol. 49, No. 2, 2013, pp. 1263-1275. https://doi.org/10.1109/TAES.2013.6494412
15. Tanaka, K., Ohtake, H., and Wang, H., "A descriptor system approach to fuzzy control system design via fuzzy Lyapunov functions", IEEE Transactions on Fuzzy Systems, Vol. 15, No. 3, 2007, pp. 333-341. https://doi.org/10.1109/TFUZZ.2006.880005