Wee-g: A MEMS gravimeter for precision gravity surveying in Security and the Environment

Wee-g：用于安全和环境领域精密重力测量的 MEMS 重力仪

• 批准号: ST/X508986/1
• 负责人: Giles Hammond
• 金额: $ 44.14万
• 依托单位: University of Glasgow
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FX508986%2F1
• 关键词: Wee; MEMS; gravimeter; precision; gravity

By measuring subtle changes (<10-8) in the acceleration of gravity we can infer the local density of nearby objects. When the density is lower (e.g. a tunnel) the local gravity becomes slightly less. While this technique is readily adopted in the oil & gas industry to (i) search for new resources (ii) perform long term monitoring at active wells, broader uptake of gravimetry in other fields is limited due to the high upfront cost of gravimeters ($80k for a Scintrex CG6), the fragility of devices and the time it takes to undertake field surveys with a single instrument. There are disruptive opportunities for gravimetry to breakthrough into other fields including environmental monitoring and security & defence. For environmental monitoring, a smaller-lighter-cheaper gravimeter will open-up opportunities for (i) deployment of sensors arrays of volcanos as a technique to image the magma plumbing system and provide resilience against eruptions, (ii) performing rapid field surveys to identify collapsed culverts, sinkholes or underground tunnels. Within the field of Security & Defence there are further opportunities of monitoring ports of entry with underwater sensors, detecting underground tunnels and monitoring compounds. Beyond this, we see opportunities in monitoring dam infrastructure, carbon capture, geothermal engineering detection/monitoring of underground aquifers. Wee-g is a precision MicroElectroMechanicalSensor (MEMS) that has been developed within the Institute for Gravitational Research (University of Glasgow). It is a spin-off from the Gravitational-Wave research activities led by Prof . Hammond. Wee-g is the world's first gravimeter, capable of monitoring the Earth tides; elastic deformations of the Earth caused by the tidal potential of the Moon and Sun. As typical gravity signals are 10-50% of the Earth ides, this is an essential measurement to show devices have sufficient stability and sensitivity. The Wee-g sensor has the potential to be made much cheaper than existing gravimeters, and thus can open-up these new opportunities in Environmental monitoring and Security & Defence. Field trials are underway with partners in both the Environmental and Security & Defence fields. Wee-g Mk I systems are being deployed on Mt Etna as part of a H2020 project (Newton-g) to monitor magma intrusion in volcanoes, and we estimate the TRL is 5. We also have a system being trialled by DSTL for underwater monitoring at a port of entry. We will use this proposal to further develop the Wee-g gravimeter (Mk II system) to put us in a prime position to spinout. We will address some of the challenges found in the Mk I system including temperature sensitivity of the MEMS chip, miniaturisation and temperature stability of the front-end electronics, and removing reliance on evaluation FPGA boards which are liable to be discontinued.

通过测量重力加速度的细微变化（<10-8），我们可以推断附近物体的局部密度。当密度较低时虽然这种技术在石油和天然气工业中很容易采用，以（i）寻找新资源（ii）在活动威尔斯进行长期监测，但由于重力仪的前期成本较高，在其他领域更广泛地采用重力测量是有限的（Scintrex CG 6为8万美元），设备的脆弱性以及使用单一仪器进行实地调查所需的时间。重力测量有突破性的机会进入其他领域，包括环境监测和安全与国防。在环境监测方面，更小、更轻、更便宜的重力仪将为以下方面提供机会：（i）部署火山传感器阵列，作为一种技术，对岩浆管道系统进行成像，并提供对爆发的恢复能力;（ii）进行快速实地调查，以确定坍塌的涵洞、天坑或地下隧道。在安全和国防领域，还有更多的机会使用水下传感器监测入境口岸，探测地下隧道和监测化合物。除此之外，我们还看到了监测大坝基础设施、碳捕集、地热工程检测/监测地下含水层的机会。Wee-g是一种精密的微机电传感器（MEMS），已在重力研究所（格拉斯哥大学）内开发。这是一个副产品的引力波研究活动领导的教授。哈蒙德。Wee-g是世界上第一台重力仪，能够监测地球潮汐;由月球和太阳的潮汐势引起的地球弹性变形。由于典型的重力信号是地球的10-50%，这是一个必要的测量，以显示设备有足够的稳定性和灵敏度。Wee-g传感器有可能比现有的重力仪便宜得多，因此可以在环境监测和安全与国防领域开辟这些新的机会。现场试验正在与环境和安全与国防领域的合作伙伴进行。Wee-g Mk I系统正在埃特纳山部署，作为H2020项目（牛顿-g）的一部分，以监测火山岩浆侵入，我们估计TRL为5。我们还有一个系统正在DSTL进行试验，用于在入境港进行水下监测。我们将利用这一建议进一步发展Wee-g重力仪（Mk II系统），使我们处于一个首要位置。我们将解决Mk I系统中存在的一些挑战，包括MEMS芯片的温度敏感性、前端电子器件的封装和温度稳定性，以及消除对可能停产的评估FPGA板的依赖。