Novel Euler-LaCoste linkage as a very low frequency vertical vibration isolator

Area of Science:

• Physics
• Mechanical Engineering
• Gravitational Wave Astronomy

Background:

• LaCoste linkage vibration isolators offer excellent ultra-low frequency vertical isolation.
• Conventional isolators use pre-stressed coil springs susceptible to creep, limiting performance and lifespan.

Purpose of the Study:

• To investigate the use of compressional Euler springs in a LaCoste structure to create a stable tension unit.
• To overcome the limitations of conventional coil springs, specifically creep, in vibration isolation systems.

Main Methods:

• Configuring compressional Euler springs into a stable tension unit for a LaCoste structure.
• Conducting a proof-of-concept experiment to measure the vertical resonance frequency of the Euler-LaCoste configuration.
• Utilizing very low creep maraging steel for spring elements.

Main Results:

• Demonstrated a vertical resonance frequency of 0.15 Hz in a 200 mm height Euler-LaCoste configuration.
• Successfully eliminated creep by using low creep maraging steel spring elements.
• Minimized spring mass and reduced the impact of parasitic resonances.

Conclusions:

• The Euler-LaCoste configuration provides a viable solution to creep in vibration isolators.
• Optimized larger-scale systems could meet the stringent requirements of third-generation gravitational wave detectors, like the Einstein Telescope.