Controller Design for Active Suspension System of ¼ Car with Unknown Mass and Time-Delay
The purpose of this paper is to present a modeling and
control of a quarter-car active suspension system with unknown
mass, unknown time-delay and road disturbance. The objective of
designing the controller is to derive a control law to achieve stability
of the system and convergence that can considerably improve ride
comfort and road disturbance handling. This is accomplished by
using Routh-Hurwitz criterion based on defined parameters.
Mathematical proof is given to show the ability of the designed
controller to ensure the target of design, implementation with the
active suspension system and enhancement dispersion oscillation of
the system despite these problems. Simulations were also performed
to control quarter car suspension, where the results obtained from
these simulations verify the validity of the proposed design.
 E. Esmailzadeh and H. D. Taghirad, “Active Vehicle Suspensions with
Optimal State-Feedback Control,” J. Mech. Sci., no. March 1997, 1996.
 M. Yamashita, K. Fujimori, K. Hayakawa, and H. Kimura, “Application
of H∞ Control to Active Suspension Systems,” Automatica, vol. 30, no.
11, pp. 1717–1729, 1994.
 C. Kim and P. I. Ro, “A Sliding Mode Controller for Vehicle Active
Suspension Systems with Non-Linearities,” Proc. Inst. Mech. Eng. Part
D J. Automob. Eng., vol. 212, no. 2, pp. 79–92, 2005.
 J. Watton, K. M. Holford, and P. Surawattanawan, “The Application of a
Programmable Servo Controller to State Control of an Electrohydraulic
Active Suspension”, vol. 218, pp. 1367–1377, 2004.
 G. Tang and F. Wang, “Suboptimal Control for Linear Large-Scale
Systems with Small Time-Delay,” Control Theory Appl., vol. 20, pp.
 D. Yue, Q.-L. Han, and J. Lam, “Network-Based Robust Control of
Systems with Uncertainty,” Automatica, vol. 41, no. 6, pp. 999–1007,
 N. S. Nise, Control Systems Engineering. 2010.
 E. Akbari and M. Farsadi, “Observer Design for Active Suspension
System Using Sliding Mode Control”, (SCOReD), 2010 IEEE, no.
SCOReD, pp. 13–14, 2010.