Current students


Section: Systems and Control

Major Research topic:
Control and estimation techniques for semi-active suspension systems in cars

Road vehicles are complex systems whose overall dynamic behaviour is strongly influenced by the suspension system: indeed, it influences both the passengers riding comfort and the vehicle stability. The most exploited solution in the automobile industry is the semi-active damper, that can be used in combination with an electronically controllable spring, either in parallel or in an integrated solution, to achieve both load-levelling and semi-active control capabilities on the vehicle. Considering the semi-active suspension, many solutions have been developed among which the most common are: ;
  • Electro-Hydraulic (EH): it is the most classical solution where it is possible by means of solenoid valves mounted inside (or outside) the damper to modify the orifice area and thus the dissipative action.
  • ;
  • Magneto-Rheological (MR): the damper contains a rheological fluid that can change its viscosity according to magnetic field which is controlled via an electric current.
  • ;
; As it is possible to understand, there are many available options when it comes to the selection of the actuators for a suspension control system. Indeed, most of the work developed in literature in the field of semi-active suspensions focuses on the modelling and control of the system’s actuator; however, in the design phase a non-negligible role is played by the sensor setup. As a matter of fact, the choice of a specific configuration determines the available vehicle signals and, consequently, the software sensing algorithms that need to be developed to obtain the full set of variables necessary for control. The aim of this research project is to develop software sensing modules, semi-active control algorithms and load levelling algorithms for cars, considering different possible setups in terms of both sensors and actuators. The idea is to propose a modular approach so that in the final control architecture a change in the choice of sensors or semi-active damper technology would not influence the implementation of the control algorithm. ┬áThe work presented in the following is performed in collaboration with the research group of Professor Wei Yintao, from Tsinghua University in Beijing. The focus of their research activity is the study of magnetorheological fluids for semi-active damper design and composite materials in relations to the design of air-springs. The purpose of the collaboration is to exploit their extensive knowledge of the components constituting the suspension system and integrating them with innovative control strategies to improve the vehicle handling and comfort performances.