Adaptive control for trailing arm suspension with hydraulic cylinder   spring under practical constraints
  This paper presents an adaptive control strategy with LQ control of a quarter-car, which is ameliorated to smoothly follow the dynamically changing reference arm angle, in order to omit the heave sensor in this study. Linearized plant parameters are initially derived from model equation and then estimated by online estimator. LQ control method provides optimal control effort with corresponding estimated plant parameters. The results of the simulation are depicted in time domain. Weighted RMS values of the consequences are suggested to assess the efficiency of the controller. Different road conditions are considered in order to reveal the performance of the controller in detail. 
Seungjun Jung and Hyeongcheol Lee
cs.SY