Comparative study of three robust observers for automotive damper force estimation. (November 2019)

• Record Type: Journal Article
• Authors: Pham, Thanh-Phong; Sename, Olivier; Dugard, Luc
• Is Part Of: IOP conference series. Volume 707(2020)
• Publication Date: 2019-11
• Subjects: Semi-active suspension -- nonlinear model -- H2 observer -- observer -- damper force estimation; Materials science -- Periodicals; 620.1105
• DOI: 10.1088/1757-899X/707/1/012014
• Languages: English
• ISSNs: 1757-8981

Abstract

Abstract: This paper aims at comparing three robust observers used to estimate the damping force of electrorheological (ER) dampers in a vehicle suspension system. Firstly, a nonlinear quarter-car model, augmented with a first-order dynamical nonlinear damper model, is developed. The first two methods are designed considering the nonlinearity as an unknown input and minimizing the effect of the unknown input disturbances (including a nonlinearity term, the measurement noise and the unknown road profile) on the estimation errors, by using an H2 and H∞ criterion, respectively. The latter method aims at minimizing only the effects of measurement noises and road profiles on the state variable estimation errors by using a H∞ criterion, while the nonlinearity is bounded through a Lipschitz condition. For implementation issue, two low-cost sensors signals (two accelerometers data from the sprung mass and the unsprung mass) are considered as inputs for the observer designs. Then, the observers are implemented in real-time on the INOVE test bench from GIPSA-lab (1/5-scaled real vehicle) to assess and compare experimentally the performances of the approaches. Both simulations and experimental results demonstrate a better effectiveness of the latter observer in terms of the ability of estimating the damper force in real-time despite the nonlinearity, the measurement noises and the road disturbances.