A structured piezo ceramic mechatronic valve for an adaptive car gas damping system

Abstract

This paper shows a new method to integrate piezoelectric actuators and amplification elements into one component. It focuses on adaptive gas-spring-dampers (GSD) for passenger cars and, particularly, a novel valve for this unit. Gas-springs for passenger cars became more popular over the last fifteen years. Its main advantage is the payload-independent eigenfrequency of the body. This independency is due to a proportional increase of spring rate and spring force. However, for any given damper rate the resonance magnification rises with the payload leading to discomfort and non-optimal driving safety. An adaptive damper suppresses this dependency. The GSD comprises two chambers with compressed gas connected by a mechatronic valve modulating the air flow between those. The valve comprises a piezo ring shored up by spokes from an inner bearing. When the piezo ring is contracted, it rotates due to the (3,1)-piezoelectric effect. This rotation modulates the valve crossing section and hence controls the air flow. The actuator design involves the specification the kinematic structure as well as raw geometric data like actuator force and motion. Here, the synthetic kinematic structures, which are based on structured piezo ceramics, are tense integrity closed. A fine tuning of geometric and material parameters is performed in an iterative process.