Hawaii Wave Surge Energy Converter (HAWSEC) OSU O.H. Hinsdale Basin

The following information and metadata applies to both the Phase I (Hydrodynamics) and Phase II (Full System Power Take-Off) zip folders which contain testing data from the OSU (Oregon State University) O.H. Hinsdale Wave Research Laboratory, from both OSU and the University of Hawaii at Manoa (UH). See zip folders provided further below in the downloads section.

For experimental data of the full system, including PTO, see Phase II dataset.

There are two main directories in each Phases's zip folder: "OSU_data" and "UH_data".

The "OSU_data" directory contains data collected from their DAQ (data acquisition system), which includes all wave gauge observations, as well as body motions derived from their Qualisys motion tracking system. The organization of the directory follows OSU's convention. Detailed information on the instrument setup can be found under "OSU_data/docs/setup/instm_locations". The experiments conducted are documented in the "OSU_data/docs/daq_logs", which provides the trial number to the corresponding data located under "OSU_data/data" in several formats (e.g., ".mat" and ".txt"). Inside the trial directory, data is provided for each of the instruments defined in "OSU_data/docs/setup/instm_locations".

The "UH_data" directory contains data collected from their DAQ. The data is stored in a ".tdms" file format. There are free plug-ins for Microsoft Excel and MathWorks MATLAB to read the ".tdms" format. Below are a few links providing methods to read in the data, but a Google search should identify alternatives sources if these no longer exist (valid as of January 2024):

Excel: http://www.ni.com/example/27944/en/
MATLAB: https://www.mathworks.com/matlabcentral/fileexchange/30023-tdms-reader

The Excel plugin is recommend to get a quick overview of the data.

The UH data is organized by directory name, in which the sub-directories for each experiment contains a directory whose name defines the wave height and period for the experimental data within. For example, a directory name "H02_T0275" corresponds to an experiment with wave height 0.1m and a period of 2.75s. For random wave data, the gamma value is also included in the directory name. For example, a directory name "H02_T0225_G18" corresponds to an experiment with a significant wave height of 0.2m, a peak period of 2.25s, and a gamma value of 1.8, with each spectra being a TMA spectrum. For the free decay experiments, the directory name is defined by the initial angular displacement. For example, a directory name "ang05_run01" corresponds to an experiment with an initial angular displacement of 5 degrees. There is a dataset in the UH data for each corresponding experiment defined in the OSU DAQ logs. The ".tdms" data is output from the DAQ at fixed intervals. Therefore, if multiple files are contained within the folder, the data will need to be stitched together.

Within the UH dataset, there are two input channels from the OSU DAQ providing a random square wave signal for time synchronization ("ENV-WHT-0010") and a high/low signal ("ENV-WHT-0012") to identify when the wave maker is active (+5V).

The UH data is logged as a collection of channel outputs. Channels not in use for the OSU testing (either Phase I or Phase II) are marked "nan" below. If the sensor is disconnected, it will record noise throughout the experiment. Below are the channel definitions in terms of what they measure:

GPS Time = time
CYL-POS-0001 = position between flap and fixed reference
CYL-LCA-0001 = force between flap and hydraulic cylinder
REC-LPT-0001 = nan
REC-HPT-0001 = nan
REC-HPT-0002 = nan
REC-HPT-0003 = nan
HHT-HPT-0001 = pressure at exhaust ("head" only)
REC-FQC-0001 = nan
REC-FQC-0002 = nan
HHT-FQC-0001 = flow at exhaust ("head" only)
ENV-WHT-0001 = nan
ENV-WHT-0002 = nan
ENV-WHT-0003 = nan
ENV-WHT-0010 = random signal from OSU DAQ
ENV-WHT-0012 = high/low signal from OSU DAQ

Also included is a calibration curve to convert the string pot data to flap pitch motion. There are two calibration curves within the file (diff sheets). One for a 50" string pot and another for a 80" string pot. The 50" sensor was used from the start of Phase I, then at some point we switched to the 80" string pot. It is not clear when exactly the transition to the longer string pot was made. If the data looks off, try the other curve. The Qualisys data from OSU should more or less match as they're both quantify the pitch.