• PermaSense - Matterhorn Instalation

Measuring Permafrost in the Alps «PermaSense»

Customer: ETH Zurich [TIK]

Permafrost is a thermal subsurface phenomenon; made-up of rock, ground and debris which is frozen throughout the year within the steep alpine bedrock. Not visible at the surface, Permafrost thaws during the summer months and can seriously affect slope stability leading to dangerous natural hazards which may hinder the safe operation of man-made infrastructure in the surrounding area. As PermaSense devices are installed and operated at high altitude in mountain regions with a permafrost environment, the system and all of its component parts must run reliably at low temperatures and be able to withstand large, daily temperature changes (in excess of 40°C) depending on sun irradiation, wind and snow.

  • PermaSense - Mountaineers

Due to the fact that the PermaSense devices are only accessible by helicopter during summer, a 2-3 year maintenance-free operation is absolutely mandatory. In order to ensure long-term, reliable operation the design of the system also had to take into the following demands into consideration:

  • extreme daily weather variations
  • danger from lightning, avalanches, rockfall, frost / ice and snow
  • limited power available from the battery
  • restricted space for electronics and battery
  • low production volumes & time frame
  • PermaSense - Matterhorn Basestation

Solution

Data is collected via a flexible, distributed wireless sensor network (WSN) which has been specially adapted to the geophysical sensors, thereby enabling reliable and high-quality measurements in the extreme environmental conditions. The system developed featured, in addition to the in-mast integration of the GPS receiver and antenna, a 2-axis inclinometer, all electronics and cables and a 12V photovoltaic system, the following:

  • wireless system with low latency data transmission
  • temperature measurements with sensor bars and thermistor chains
  • sensor nodes with “crack meter”
  • 2-dimensional measurement of gap movement

Our Contribution

Design, development and industrialisation of miniaturised wireless sensors based on functional (hardware) model, including:

  • development of wireless GPS-system (HW)
  • specialised sensors and electronics
  • robust package
  • low sampling rates (1-60 min)
  • battery operated (3 year lifespan)
  • networked devices with wireless data transfer
  • production of small batches of all product variants
  • 6 months from concept to first production batch
  • PermaSense - Summit
  • PermaSense - System Archictecture
  • PermaSense - System