Broad Frequency Range Decoupling Based on Elastic Bedding and Zero Stiffness Design

This paper highlights the challenge of designing a high-mass decoupling system for a broad frequency range, taking into account several practical requirements for implementation in ultra-high precision manufacturing. This includes avoiding conventional joints to prevent particle abrasion and meeting mechanical restrictions such as the material strength and buckling of the used helical compression springs. To achieve a particular low frequency isolation, a three dimensional layout based on a zero stiffness approach is designed. Compared to conventional decoupling systems, this approach enables the reduction of the overall stiffness, and therefore the system’s natural frequency, without sacrificing the load capacity. The demand for high frequency isolation is met by the design of an elastic bedding of the system, allowing the use of small helical springs with high natural frequencies. The system layout is determined by numerical optimization of the design parameters. It was possible to design a system to decouple a mass of \({1000}\,\text {kg}\) in a frequency range from \({1}\,\text {Hz}\) to \({1000}\,\text {Hz}\) . Compared to a conventional decoupling system without zero stiffness design, a reduction of the system’s natural frequency by approximately 80% was achieved.