Opossum

The OPOSSUM project aims at the development and testing of accelerometers and acceleromter networks with the potential to outperform state of the art sensing technology. Accelerometers are powerful, highly versatile and cost-efficient tools used in a wide range of application with specific requirement in terms of frequency response and sensitivity. Accelerometers can record acceleration with frequencies of 1Hz to more than 1MHz. In seismology accelerometers are used in two subfields, among others:

• Imaging for seismic velocities and their evolution with time, which are related to transients in material properties, fluid flow and stress evolution
• Monitoring of tiny fractures, cracks or micro earthquakes that are an indication of material fatigue or accelerating failure processes.

Accelerometers can be deployed on concrete or steel, for example for structural health monitoring of buildings, dams, bridges or wind turbines; they can be deployed in deep boreholes, detecting micro-earthquakes during the reservoir creation of geothermal activity, oil and gas exploration and operations, or to monitor mining operation and the integrity of nuclear waste repositories etc. They can also be used as scientific instruments to better understand fluid-rock interaction or the initiation and propagation of catastrophic natural and induced earthquakes.

The OPOSSUM project exploits theoretical and experimental advances in the field of opto-mechanics in the last decade as well as significant improvement on micro-fabrication and modelling of high-quality integrated photonics circuits (PIC) and ultra-high Q (UHQ) mechanical resonators. These two technological building blocks are at the core of a new generation ultra-sensitive accelerometers that are developed at the Centre Suisse d’Electronique et de Microtechnique (CSEM), with capabilities of exceeding the current generation of accelerometers in numerous ways.