Tilt Meter A603 – Solving Technical and Scientific Issues in Tilt Measurement

Tilt Meter A603

Solving Technical and Scientific Issues in Tilt Measurement

Since 2004, the Institute of Technology and Renewable Energies of the Canary Islands has started monitoring the Canary Islands. Since 2011, the institute has collaborated with the Canary Islands Volcano Research Institute (INVOLCAN) to conduct precise monitoring of the islands through a network of over 30 differential GPS stations. This network is particularly dense on Tenerife Island, where 12 permanent GPS receivers have been deployed. The data collected by these receivers is automatically processed using Bernese software, providing essential tools for geodetic monitoring of Tenerife Island.

Since 2016, the volcanic system on Tenerife Island has been in a state of hydrothermal instability. In particular, the diffuse carbon dioxide flux at the Teide volcano crater has significantly increased, which may be related to the injection of magma source fluids into the hydrothermal system of Tenerife Island. Additionally, since July 2017, an increase in observed background microseismic activity has been noted, further reflecting the pressurized state of the volcanic system. However, so far, the GPS global positioning system network has not recorded any significant ground deformation beyond the instrument error range, indicating that despite the volcanic system being in an unstable state, large-scale ground deformation has not yet occurred.

In order to enhance the precision of geodetic monitoring on Tenerife Island and detect small ground deformations below the sensitivity of the GPS global positioning system network, the Canary Islands Volcano Research Institute (INVOLCAN) began deploying high-gain tiltmeters (Jewell A603-C) around Mount Teide since June 2019.

Currently, the tilt measurement network consists of three tiltmeters, all located near existing seismic or GPS global positioning system sites to fully utilize the infrastructure and data collection capabilities of these sites. The data collected by the tiltmeters is automatically downloaded via Universal Mobile Telecommunications System (UMTS) connection and processed professionally on a daily basis to ensure the timeliness and accuracy of the data.

This instrument has high sensitivity (<2.5nrad) and requires very careful installation and calibration. Its sensor is equipped with worm gear leveling feet; however, manual leveling fails due to excessive sensitivity, and the weight of the operator can cause the instrument to exceed its range. To address this, the Canary Islands Volcano Research Institute (INVOLCAN) developed a remote adjustment robotic system using an Arduino Mega 2560 microcontroller, adjusting the leveling worm gear with two servo motors and switching gain with another servo motor. This system can be accessed and operated through an internal web page, allowing the use of Arduino Ethernet to drive the servo motors and check the leveling status of the tiltmeter platform.

High-precision GPS positioning system receivers can be used for long-term monitoring of surface displacement and settlement monitoring, with horizontal positioning accuracy of ±2.5mm; vertical positioning accuracy of ±5mm.

The above content is quoted from: Barrancos, J., Przeor, M., D’Auria, L., Cabrera, I., Montañez, A. C., Hernández, P. A., and Pérez, N. M.: The new tiltmetric network of Tenerife: technical and scientific issues, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4819,

The A603 platform-mounted tilt meter is designed to fill the gap left by the old 520M tilt meter, equipped with the same worm gear screw leveling legs as the 520M. The A603 also includes two switchable gain settings and two low-pass filter setting switches.

The A603 has high resolution, with sensitivity of <2.5nrad, and almost zero long-term drift; output is stable ±8V DC voltage (±16V differential). The A603 is robust and reliable, making it the choice for volcanic monitoring, high-precision geotechnical engineering, precise measurement, radar platform leveling, and high-accuracy tilt monitoring applications.