Developing a new calibrated pressure sensor for the Ocean Observatories Initiative Cabled Array and other applications

为海洋观测站计划电缆阵列和其他应用开发新型校准压力传感器

• 批准号: 1829486
• 负责人: William Wilcock
• 金额: $ 54.53万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1829486&HistoricalAwards=false
• 关键词: Developing; new; calibrated; pressure; sensor

Measurements of seafloor pressure are useful for understanding the earth and the ocean because they are sensitive to changes in the height of the seafloor and the weight of the overlying water and atmosphere. The best pressure sensors drift unpredictably so their output cannot be used to resolve long terms signals such as the steady buildup of strain between subduction zone earthquakes and long term changes in the mass of the oceans. Drift also makes existing pressure sensors less sensitive to shorter-term signals such as those from slow-slip earthquakes and ocean eddies. A new method has been developed to remove drift using the internal pressure inside the instrument housing as a reference and has been tested successfully with a seafloor prototype. This project will redesign the prototype so that the instrument is more robust, better calibrated, more compact and lower power. It will be attached to the Ocean Observatories Initiative Cabled Array on Axial Seamount, a volcano that is inflating rapidly following an eruption in 2015. The engineering effort will be led by a female engineer in a field where women are underrepresented and the project will train a graduate student in a technical project where they will learn to work with both engineers and scientists. The cruises that service and deploy instruments on the Ocean Observatories Initiative Cabled Array incorporate a large number of undergraduate students, and one will be engaged to conduct a project related to this instrument.The A-0-A method is a new approach to calibrating pressure sensors to remove drift. Periodically, a valve is used to switch the pressure sensor for a short interval from measuring the pressure in the ocean to measuring the pressure inside the instrument housing. The drift can then be determined by comparing the pressure readings to an accurate barometer. The A-0-A method has the potential to substantially reduce the drift of long-term seafloor pressure records in a much more economical way than current approaches. The first non-proprietary seafloor tests at 900 m in Monterey Bay on the MARS cabled observatory suggests that A-0-A calibrations may reduce pressure sensor drift to as little as 1-2 mm/year in 1000 m of water. However, design improvements are required to remove known sources of error and a side-by-side seafloor test is essential to verify the technique against established methods of drift removal. The first deployment of the redesigned instrument on Axial Seamount will allow comparisons with the absolute pressure measurements of the Scripps Institution of Oceanography Self-Calibrating Pressure Recorder (an instrument that uses a dead weight tester for periodic calibrations) and the relative pressure measurements obtained from repeat closed-loop mobile pressure recorder surveys, both of which have an uncertainty of ~1 cm of water. The cabled sensor can then be used for future vertical geodetic studies of the Cascadia subduction zone megathrust aimed at understanding patterns of fault locking, creep and slow slip.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

海底压力的测量对于理解地球和海洋很有用，因为它们对海底的高度以及上层水和大气的重量敏感。 最好的压力传感器会不可预测地漂移，因此无法使用它们的输出来解决长期信号，例如俯冲区地震之间的应变稳定积累和海洋质量的长期变化。 漂移还使现有的压力传感器对短期信号（例如慢滑地震和海洋涡流的信号）的敏感性降低。已经开发了一种新方法来使用仪器外壳内部的内部压力作为参考来清除漂移，并已通过海底原型成功测试了漂移。 该项目将重新设计原型，以使仪器更健壮，校准更好，更紧凑和更低的功率。 它将连接到轴向海山上的Ocean Obseraties Initiative Initiative Initiative，这是一座火山，该阵列在2015年爆发后正在迅速膨胀。工程工作将由女性工程师领导，该领域的女性工程师将在女性中占主体不足的领域，该项目将在一个技术项目中培训一个技术项目，他们将学习与工程师和科学家一起工作。 在海洋天文台上提供服务和部署工具的巡游倡议电缆阵列包含了大量的本科生，并且将订婚一个与该工具有关的项目。A-0-A方法是一种校准压力传感器以消除漂移的新方法。 周期性地，使用阀门将压力传感器短时间从测量海洋的压力转换为测量仪器壳体内部的压力。 然后可以通过将压力读数与精确晴雨表进行比较来确定漂移。 A-0-A方法有可能以比目前的方法更经济地减少长期海底压力记录的漂移。 在火星电缆天文台的蒙特雷湾900 m处的第一个非专有海底测试表明，在1000 m的水中，A-0-A校准可能会将压力传感器漂移降低至1-2 mm/年。 但是，需要进行设计改进以消除已知的误差源，并且并排海底测试对于验证既定的固定漂移方法的技术至关重要。 重新设计的仪器在轴向封口上的首次部署将允许与Scripp的绝对压力测量进行比较。然后，该传感器可用于对Cascadia俯冲带的未来垂直测量研究Megathrust，旨在理解故障锁定，蠕变和慢速滑移模式。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的评估来通过评估来获得支持的。