Multi-instrument turbulence toolbox (MITT): Open-source MATLAB algorithms for the analysis of high-frequency flow velocity time series datasets

The measurement of flow velocity at high frequencies (20-200 Hz) has been made easier over the last couple of decades by the development and commercialization of a variety of instruments, many of which are capable of measuring multiple sampling volumes simultaneously. A variety of methods has been proposed to remove errors in velocity time series and classify the quality of data. However, most methods are applied using custom algorithms written to treat custom data formats and remain hidden from a wider audience. The objective of this paper is to introduce and document a new set of open-source algorithms, written in Matlab, that comprise the Multi-Instrument Turbulence Toolbox (MITT). The algorithms are designed to: (i) organize the data output from multiple instruments into a common format; (ii) present the data in a variety of interactive figures for visualization and assessment; (iii) clean the data by removing data spikes and noise; and (iv) classify data quality. We hope that these algorithms will form the nucleus of an evolving toolbox that will help to accelerate the training of hydraulic researchers and practitioners, ensure a consistent application of methods for turbulence analysis, remove the bias of poor quality data from scientific literature, and ease collaboration through the sharing of data and methods.