38. Evaluation of Traveling Wave Models for Carangiform Swimming Based on Complex Modes

The research problem we considered is to evaluate the accuracy of traveling wave model proposed in the literature as the kinematic model for fish midline motions during straight forward carangiform swimming. Almost all the literature uses a sinusoidal traveling wave model with constant wavelength and frequency for the model of lateral movements of body. We acquired raw data of midline lateral movements for three Carangiform fish from the resources available in the literature. On the other hand, we built the traveling wave models based on the format used in literature. We used COD (complex orthogonal decomposition) to decompose the total motion associated with the raw data and with the traveling wave model into complex modes and derive the wave properties. Through this analysis we evaluated the traveling wave model accuracy. The criteria we chose for comparison was the dominant modes’ shape and their number, frequencies and wavelength associated to each mode. As a result of this analysis, we found that both the lab data and the traveling wave model, have a single dominant mode. The main difference between these two was that the phase change rate with respect to location and with respect to time is not constant in raw data, however in the traveling wave model we used constant frequency and wavelength.