Preliminary Study of Parameter Optimizations Toward a Lab-Designed Acoustic-Based Volume Measuring System for Weights

The purpose of this study is to investigate the existence of the optimal sound source driving signal toward a laboratory-designed acoustic-based volumeter for weights. The finite element (FE) simulation method is used for simulating the measuring system and predictively determining the qualities of the optimal sound source driving signal, including frequencies and amplitudes. Then, experimental studies are conducted to verify the predictions acquired by the FE simulation method. The volume measurement of 1-100 g weight is carried out, and the sound source driving signals that minimize the error of the weights' volume measurements are treated as optimal. As the results, experimental measurements verify that the findings carry out by simulations. The uncertainty evaluation of the optimized acoustic volumetric measurement results is provided and shows that the extended uncertainties of the volumetric measurement of 50-100 g weights are less than 6 x 10(-4). The relative expanded uncertainty of 1-20 g weights satisfy the requirement of the volumetric measurement expanded uncertainty for Class E1 weights according to OIML Recommendation R111.