Research Projects
My current project is developing a micro electro mechanical system (MEMS) gravity sensor in the Institute for Gravitational Research (IGR) and the James Watt Nanofabrication Centre (JWNC). The ability to measure tiny variations in gravitational acceleration (g), allows one to see not just the Earth's gravitational pull, but the influence of smaller objects. The more accurate the gravimeter, the smaller the objects one can see. This capability can result in high impact, real-world applications in many spheres. It allows one to see the density variations of the ground under our feet and therefore find things difficult or impossible to find by other means. From tracking magma moving kilometers under volcanoes before eruptions, to revealing hidden tunnels or buried services; from finding new oil and gas reserves, to monitoring nuclear waste burial sites; gravimetry gives us the ability to both save lives and create revenue.
Most of us already carry a similar device in our pockets. Smart phones utilise a MEMS (micro electro-mechanical system) accelerometer that can measure whether the phone is up, down, or sideways, and allows the phone to turn the screen accordingly. These aren’t nearly sensitive enough to be used for the above applications but they are cheap, light weight and mass-producible. Commercial gravimeters are also available that can be used for the applications above, but only if you can carry the 50kg system and pay the $100,000 US bill. We have designed a device the size of the accelerometer in your phone, using the same cheap methods and material (Silicon), but significantly more stable and sensitive. In a recent Nature paper, it was shown that this device is capable of measuring the Earth tides – the tiny elastic distortion of the Earth’s crust caused the gravitational pull of the Moon and Sun. This is the first such measurement with a MEMS sensor, demonstrating that it is the first MEMS gravimeter. This device will be cheap enough to network, small enough to be flown on a drone, and could therefore be a transformative technology in the fields of (amongst others) geophysical exploration, environmental monitoring, and defence.
Read about this work in more detail in this recent Nature publication, or in the companion article by Hazel Rymer.
Most of us already carry a similar device in our pockets. Smart phones utilise a MEMS (micro electro-mechanical system) accelerometer that can measure whether the phone is up, down, or sideways, and allows the phone to turn the screen accordingly. These aren’t nearly sensitive enough to be used for the above applications but they are cheap, light weight and mass-producible. Commercial gravimeters are also available that can be used for the applications above, but only if you can carry the 50kg system and pay the $100,000 US bill. We have designed a device the size of the accelerometer in your phone, using the same cheap methods and material (Silicon), but significantly more stable and sensitive. In a recent Nature paper, it was shown that this device is capable of measuring the Earth tides – the tiny elastic distortion of the Earth’s crust caused the gravitational pull of the Moon and Sun. This is the first such measurement with a MEMS sensor, demonstrating that it is the first MEMS gravimeter. This device will be cheap enough to network, small enough to be flown on a drone, and could therefore be a transformative technology in the fields of (amongst others) geophysical exploration, environmental monitoring, and defence.
Read about this work in more detail in this recent Nature publication, or in the companion article by Hazel Rymer.