Study on an improved variable stiffness tuned mass damper based on conical magnetorheological elastomer isolators

Use of a variable stiffness tuned mass damper (VSTMD) is an effective approach to reduce the dynamic responses of a structure with shifting natural frequencies. Magnetorheological elastomer (MRE) isolators can be used to build VSTMD due to their tunable stiffness by applying a magnetic field. However, conventional MRE isolators show deformation limits, huge energy consumption and uneconomic production. Focused on developing a MRE VSTMD system to improve this situation, a conical MRE isolator has been proposed and tested. Compared to conventional MRE isolators, the conical isolator shows much higher efficiency, better overall stability, greater deformability and a larger tunable range. The experimental results indicate that the prototype can provide a 46.29% increase in frequency and a 75 N control force range with a 25W power source. The quick responding MRE VSTMD system has the potential to accurately provide the desired stiffness in two directions to achieve a better structure control.