Effects of section configurations on the dynamic responses of an integrated quasi-zero isolator

In this research, a new passive-type integrated quasi-zero stiffness isolator with variable cross-section (IQZS-VCS) characteristic is proposed in order to extend the application fields. Compared with the integrated quasi-zero stiffness isolator with uniform cross-section (IQZS-UCS), the IQZS-VCS isolator has more adjustable structural parameters and can enhance vibration attenuation performance in lower-frequency region. Based on the developed static model, the nonlinear force and nonlinear stiffness characteristics of the IQZS-VCS isolator are evaluated using different design parameters. Furthermore, the effects of different factors on vibration reduction ability of the isolating system are addressed in terms of amplitude-frequency response and force transmissibility. Compared with a traditional linear, IQZS-UCS and conventional three-spring-type quasi-zero stiffness isolators, the proposed isolator exhibits better low-frequency and wide-band isolation performance. Quasi-static and electromagnetic exciting tests reveal that the developed theoretical models and related calculation results of the IQZS-VCS isolator are correct, providing an innovative solution and insight for broadband isolator. © 2024 Elsevier Ltd