Optical non-contact floating object tracking using an open-source library

In this paper, an optical non-contact low budget method for tracking the position of multi-object is presented for marine/off-shore laboratory applications. Particular focus is given at the wave energy field and the analysis of floating wave energy converters dynamics. The measurement of the position and orientation is often a key point in this context, achieved nowadays with different standard technologies. Typically a base requirement for a measurement system is to be accurate and precise, without affecting the dynamical and statical behavior of the system itself. Video based systems satisfy these points, but they are typically prohibitively expensive. Through the article a low budget one-camera video based system is presented and compared with other two standard methods: direct physical measurement and inertial motion unit (IMU). The system was tested both, in a dry environment and in waves. Results show an average error below 4%, with increased high signal accuracy and precision in the low frequency components but also increased high frequency noise components. Further investigation will be addressed to the implementation of a hybrid system, where the corrupted high frequency information can be replaced by the IMU signal.