Optimization of biomimetic propulsion in a fish like robot

The study of biomimetics is largely driven by the desire to integrate design advantages found in the natural world to experimental devices and, ultimately, practical machines. The work contained herein consisted of the construction of a biomimetic carangiform robotic fish as a functional experimental apparatus, the prediction of propulsive forces based on mechanical fish tail linkage kinematics using a lift based theory, an experimental process to obtain fish swimming velocity data for a number of different swim profiles, and the comparison of theoretical to experimental results. The robot constructed possesses a propulsive section with five short links capable of fitting the sinusoids produced by Lighthill’s model of fish tail motion accurately. A lift based model was developed and estimated the net propulsive force generated per square foot of foil to be 6.53 lbf/ft2 of foil, 7.78 lbf/ft2, and 7.95 lbf/ft2 for the three cases evaluated theoretically. The trends in the experimental fish swimming velocity data point to convergence at 0.375 ft/s, 0.40 ft/s, and 0.42 ft/s in the three varied C-term wave envelope coefficients tests corresponding to the force estimates above. The experimental data points to validation of the theoretical model, and it has the potential to be a useful tool in planning fish tail kinematics in future work