Robust Controller Design for Hydraulic Dipod Platform Based on 2-DOF H Controller Synthesis Framework

2자유도 H 제어기 종합 프레임웍에 기반한 유압식 Dipod 플랫폼의 강인제어기 설계

  • Received : 2012.10.25
  • Accepted : 2013.03.20
  • Published : 2013.06.01


A hydraulic dipod platform is used for tracking and stabilizing an antenna system to designate a satellite on a moving vehicle. The 2-DOF controller is very well suited to this controller design object because it is more flexible than the 1-DOF controller when the design object is not only the consideration between stabilizing and tracking but also the trade-off between performance and robustness. The 2-DOF controller synthesis based on the $H_{\infty}$ framework is divided into two design procedures. In this hydraulic dipod platform example, the single-step method shows better performance whereas the two-step method shows better robustness. The difference between these two synthesis results is compared using the structural property of the interconnection system matrix.


2-DOF(TDF) Robust Control;Dipod Platform;$H_{\infty}$-LSDP;Feedback Controller;Feedforward Compensator


  1. Redheffer, R. M., 1960, "On a Certain Linear Fractional Transformation," Journal of Maths. Phys., 39, pp. 269-286.
  2. Glover, K. and McFarlane, D., 1989, "Robust Stabilization of Normalized Coprime Factor Plant Descriptions with $H_{{\infty}}$ -Bound Uncertainty," IEEE Transactions on Automatic Control, Vol. 34, Issue 8, pp. 821-830.
  3. McFarlane, D. and Glover, K., 1992, "A Loop Shaping Design Procedure Using $H_{{\infty}}$ Synthesis," IEEE Transactions on Automatic Control, Vol. 37, Issue 6, pp. 759-769.
  4. Skogestad, S. and Postlethwaite, I., 2001, "Multivariable Feedback Control : Analysis and Design," 2nd Edition, JOHN WILEY & SONS.
  5. Gu, D.-W., Petkov, P. H. and Konstantinov, M. M., 2005, "Robust Control Design with Matlab," Springer.
  6. Taik-Dong Cho, Sang-Min Yang, 2007, "Robust Control of Hydraulic Operated Gimbal System," Journal of Mechanical Science and Technology, 21, pp. 755-763.
  7. Doyle, J. C., Glover, K., Khargonecker, P. P. and B. A. Francis, 1989, "State-Space Solutions to Standard $H_{2}$ and $H_{{\infty}}$ Control Problems," IEEE Trans. Aut. Contr., AC-34, pp.831-847.
  8. Limebeer, D. J. N., Kasenally, E. M. and Perkins, J. D., 1993, "On the Design of Robust Two Degree of Freedom Controllers," Automatica, Vol. 29, No. 1, pp. 157-168.
  9. Merritt, H. E., 1967, "Hydraulic Control Systems," John Wiley & Sons, pp. 145-150.