Feasibility study of a Ultra-Low-Cost 3D-Printed WaveBuoy for water Wave Measurement

This paper presents a feasibility study for producing a low-cost wave buoy system for measuring ocean waves using 3D printing technology and inertial measurement unit (IMU) data. The buoy incorporates a SparkFun OpenLog Artemis (OLA) data logger with integrated accelerometer, gyroscope, and magnetometer sensors housed within a 3D-printed watertight hull. The custom firmware allows the use of a GPS to ensure absolute time synchronization with the UTC reference for the IMU data. The design addresses key requirements including water tightness, stability, directional independence, and cost-effectiveness. Comprehensive validation tests were conducted including sensor calibration, power consumption analysis, stability testing, and wave tank experiments. We demonstrate that the buoy is capable of accurately measuring sinusoidal wave-induced motions across a broad range of frequencies. Dedicated accelerometer calibration tests indicate a slight underestimation of acceleration amplitudes. However, this bias is not observed in the final wave tank experiments. At the highest excitation frequencies, the resonant response of the buoy results in an overestimation of the measured motion amplitudes. This behavior is consistent with theoretical expectations based on the natural (eigen) frequencies of the buoy. The total materials cost remains approximately $200, making it suitable for deployment in arrays for oceanographic research in the ocean or the wave tank. The feasibility study concludes that 3D printing technology combined with modern IMU sensors provides a viable approach to developing affordable wave measurement systems for scientific and engineering applications, both in the field and in the laboratory.