A concept for semi-active vibration control with a serial-stiffness-switch system

This work deals with a new semi-active vibration control concept with a serial-stiffness-switch system (SSSS), which can be seen as one and a half degree-of-freedom system. The proposed switched system is mainly composed of two serial elements, each of which consists of one spring and one switch in parallel with each other. This mechanical structure benefits from a specified switching law based on the zero crossing of velocity in order to realize vibration reduction. In contrast with conventional ways, the new system is capable of harvesting vibration energy as potential energy stored in springs, and then applies it to vibration reduction. In this paper, the concept is characterized, simulated, evaluated, and proven to be able to improve the system response. The equivalent stiffness and natural frequency of the switched system are mathematically formulated and verified.