Series Active Variable Geometry Suspension for Road Vehicles

A new family of electro-mechanical active suspensions that offers significant advantages with respect to passive and semiactive suspensions, while at the same time avoiding the main disadvantages of alternative active solutions, is presented in this paper. The series active variable geometry suspension takes a conventional independent passive or semiactive suspension as its starting point, and improves its behavior by actively controlling the suspension geometry with an electro-mechanical actuator. The advantages of this type of suspension are discussed and its simplest variant is studied in detail. Insight on the design process, as well as on the actuator modeling and selection is provided. Moreover, a control system for pitch attitude control of the chassis is presented. Simulation results obtained with a high-fidelity, full-vehicle, nonlinear model of a high-performance sports car that includes actuator dynamics and saturation limits are shown to confirm the potential of the proposed system.