Vibration isolation via a scissor-like structured platform

Vibration isolation using a hybrid lever-type isolation system with an X-shape supporting structure

“…1. The supporting structure is an n-layer scissor-like or X-shape structure with horizontal spring [16]. Each layer has two rods combined with one joint, and length of each rod is 2l.…”

“…The restoring force in the horizontal spring is linear with a stiffness k l . The n-layer X-shape structure can provide high static and low dynamic stiffness [16], which is very important to obtain good and stable isolation both in the low and high frequency range.…”

“…However, in some cases complicated nonlinear phenomena could also happen if system parameters are not well designed, incurring potentially worse stability problems. Recently, a passive scissor-like structured isolation system was proposed and studied in [33,16], where an excellent high-static-low-dynamic stiffness property can be achieved by flexibly designing structural parameters.…”

A torsion quasi-zero stiffness vibration isolator

“…Further, Shaw et al [11] built an apparatus of this type of QZS isolator, and tested the vibration isolation performance under base excitations, which shows a greater isolation region and a lower peak response than the equivalent linear system. Sun et al [12] proposed an isolation platform with n-layer scissor-like truss structure to achieve QZS property. Carrella et al [3] developed a QZS isolator by combining coil springs and magnets arranged by attracting configuration to act as negative stiffness element.…”

A multi-directional vibration isolator based on Quasi-Zero-Stiffness structure and time-delayed active control

“…Timedelay in active control is considered as an adjustable parameter because appropriate value of time delay can induce different vibration control mechanisms such as vibration energy transmission in different modes [26,27], absorbing vibration energy [28,29] or changing equivalent stiffness and damping properties [30,31]. For the previous analysis, it is found that assembling the time-delay active control device in vertical direction in the one-direction QZS-VI, the resonant peak is reduced while the response in high frequency range would be increased when increasing the value of control strength and time delay [20].…”