Sunderland A, Naveh Y, Ju L, Blair D G, Lockwood R, Anderson B, Dransfield M
Physics Department, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
Xcalibur Multiphysics, 10 Compass Road, Jandakot, WA 6164, Australia.
Rev Sci Instrum. 2022 Jun 1;93(6):064502. doi: 10.1063/5.0091900.
Vibration in the audio frequency band affects the performance of rotating gravity gradiometers used for airborne mineral exploration. This is probably due to translation to rotation coupling inside the gradiometer platform. It was found that the DC gravity gradient signal was proportional to the square of the third time derivative of position, or jerk squared. The demanding airborne environment for such instrumentation demands a light weight broadband acoustic shield and vibration isolator. This paper presents the design principles for such an isolator, based on vibration isolated spherical shell structures. Performance data are presented as well as flight test data that demonstrated a 14% gravity gradient noise reduction compared with an unshielded instrument.
音频频段的振动会影响用于航空矿物勘探的旋转重力梯度仪的性能。这可能是由于梯度仪平台内部的平移到旋转耦合所致。研究发现，直流重力梯度信号与位置的三阶时间导数的平方成正比，即加加速度的平方。此类仪器在苛刻的航空环境中需要轻质宽带隔音罩和隔振器。本文基于隔振球形壳结构，介绍了这种隔振器的设计原理。文中给出了性能数据以及飞行测试数据，这些数据表明，与未加屏蔽的仪器相比，重力梯度噪声降低了14%。
