Adaptive ride comfort and attitude control of vehicles equipped with active hydro-pneumatic suspension

Saglam, Ferhat
Ünlüsoy, Yavuz Samim
In this study, an active suspension for combined ride comfort and attitude control of a vehicle equipped with hydro-pneumatic (HP) suspension system is developed. The state-dependent Riccati equation (SDRE) control is employed in the design of the active suspension controller. A detailed sensitivity analysis is performed to examine the effects of the selection of weighting coefficients on the ride comfort and attitude control. According to the results of the sensitivity study, three different sets of fixed weighting coefficients and a fourth set with adaptive weighting coefficients are developed. The adaptive weighting coefficients are implemented by the state constraint in the SDRE formulation. The controller is tuned mainly for ride comfort at low suspension deflections and for keeping the proper vehicle attitude at higher suspension deflections. Simulation results show that the active suspension with the adaptive weighting is successful in improving both ride comfort and the vehicle attitude.


Analysis and Design of Passive and Active Interconnected Hydro Pneumatic Suspension Systems in Roll Plane
Sağlam, Ferhat; Ünlüsoy, Yavuz Samim (2015-05-19)
In this study, analysis and design of a half car model in roll plane with passive and active unconnected and interconnected Hydro-Pneumatic (HP) suspension systems are made. An interconnection configuration with a connection between the piston side oil volume and rod side oil volume of the right and left suspensions, respectively, is considered. The performance of the active unconnected HP and interconnected HP suspension systems are compared in terms of ride comfort and handling. Nonlinear mathematical mod...
State Dependent Riccati Equation Control of an Active Hydro Pneumatic Suspension System
SAĞLAM, FERHAT; Ünlüsoy, Yavuz Samim (2014-10-01)
In this study, a nonlinear active Hydro-Pneumatic (HP) suspension system is modelled. The HP suspension system model is then incorporated into the quarter car model and a nonlinear controller for the vehicle system is developed. A linear structured model with state dependent matrices of the nonlinear quarter car model is derived for use in controller design. A nonlinear control method, State Dependent Riccati Equation control (SDRE) is used to attenuate sprung mass acceleration, suspension deflection, and t...
Optimization of ride comfort for vehicles equipped with passive and active hydro-pneumatic suspensions
Sağlam, Ferhat; Ünlüsoy, Yavuz Samim; Department of Mechanical Engineering (2016)
The main objective of this study is the optimization of ride comfort performance of vehicles equipped with Hydro-Pneumatic (HP) suspension systems. In order to improve ride comfort performance together with handling behavior as a constraint, active-passive, and unconnected-interconnected HP suspension systems are included in the study. The basic HP suspension model is developed and validated by experiments. Various HP suspension systems of increasing complexity are modeled, and their dynamic characteristics...
Comparison of different active suspension control strategies using half car model
Büyüker, Banu Çiçek; Bayar, Kerem; Department of Mechanical Engineering (2020-12-30)
Among other advances in ground vehicle technology, active suspension systems play an important role in improving ride comfort, handling and road holding vehicles. Ride comfort is affected by vehicle motions, such as body bounce, pitch and roll, but also limiting wheel travel and suspension deflection is important for road holding performance. The main motivation of this study is designing different control strategies for active suspension systems equipped with a linear electric motor and making a comprehens...
Sliding mode control for non-linear systems with adaptive sliding surfaces
Durmaz, Burak; Özgören, Mustafa Kemal; SALAMCİ, METİN UYMAZ (2012-02-01)
This study covers the sliding mode control design with adaptive sliding surfaces for a class of affine non-linear systems, which can be described by (x) over dot = A(x)x + B(x)u + f(x) + d(x, t). The main streamline of the study is the sliding surface design for such systems. The sliding surfaces are designed to be moving with varying slopes and offsets. The varying sliding surface parameters are determined by solving the state-dependent Riccati equations online during the control process. Thus, the sliding...
Citation Formats
F. Saglam and Y. S. Ünlüsoy, “Adaptive ride comfort and attitude control of vehicles equipped with active hydro-pneumatic suspension,” INTERNATIONAL JOURNAL OF VEHICLE DESIGN, pp. 31–51, 2016, Accessed: 00, 2020. [Online]. Available: