What is a Tilt Current Meter
The relatively high cost of Acoustic Doppler Profilers (ADPs) has placed practical limits on the use of these meters in marine research projects. One approach to reducing the cost of current measurements has been the re-invention of the Tilt Current Meter (TCM). Developments in accelerometers, magnetometers and low-power non-volatile memory have made it possible to make small, accurate and inexpensive TCMs.
Simple to Use
Improved Tilt Sensor
The tilt sensor uses both an accelerometer (tilt) and magnetometer (compass) enabling accurate direction measurements without needing to know the orientation of the device when deployed.
Tough Enclosure
Built from PVC or Titanium, the TCMs can operate in as little as 11 inches of water to 10,000 meters
Easy to Deploy
The TCM is light weight and is typically deployed using a concrete paver or led diving weight. Depending on the water depth, the meters are deployed by divers, bridal mount from a small vessel or ROVs for deeper depths.
Flexible Sample Rates, Large Memory & Long Battery Life
The meter can sample up to 64 times per second. Burst mode allows for variable rate logging at user defined interval.
8 GB memory card virtually eliminates memory concerns.
Powered by a user-replaceable full size Lithium A battery, the meter can operate at 4Hz sampling for a year.
Domino Software
Domino Software for Windows is Lowell Instrument's Python based, open source software for use with our MAT-1 data loggers and TCM Tilt Current Meters. The easy-to-use Domino software is used to create a setup file, start and stop the meters, and converts binary data to a CSV format.
Domino is also Head of Security at Lowell Instruments!
Testimonials
Ocean currents were estimated from the drag on a pendulum [TCM] attached to the sea ice that measured accelerations and magnetic field strength vectors in the all three spatial dimensions. It is a promising new and simple technology that we successfully put to the test. Such a network holds the promise to revolutionize under-ice ocean sampling in polar regions.
Andreas Muenchow
University of Delaware
Professor at the School of Marine Science and Policy
In order to calculate oxygen flux (net community production, NCP) over the seagrass bed it was important to show that there was tidally driven uniaxial current flow over the bed which allowed us to determine NCP using an ‘upstream-downstream’ approach (any changes in pH or dissolved concentration over the bed were due to seagrass productivity along the transect line). The tilt current meters were very easy/straightforward to program and deploy. We did not have to worry about the orientation of the meter or having it deployed exactly level as we do for the ADVs and ADPs. Transportation was also much easier. We could pack the current meters (buoyant part) in a regular suitcase and hand carry the loggers on the plane. Our other instruments required their own cases which quickly becomes expensive for field work.
Heidi Hirsh
Stanford University