The use of robophysical mantis shrimp models to study ultra-fast "impulsive" biological an synthetic systems

Peacock mantis shrimp are considered the fastest strikers in the animal kingdom, achieving punches in the range of 14-23 m/s in water – fast enough to create cavitation bubbles and break clam shells. They accomplish this with a dactyl heel striking appendage only a few centimeters long. In order to study these remarkable capabilities, we leverage recent breakthroughs in multi-scale, multi-material rapid fabrication to create a physical model of the mantis shrimp at scale. The rapid release of energy storage is accomplished through a torque reversal mechanism with a spring in parallel. Our preliminary design is capable of achieving a 15.5 m/s peak velocity, 67.4% the peak velocity of biological mantis shrimp. We’re able to demonstrate the formation of cavitation bubbles in striking, and can produce peak forces of 100 N. Our analytical dynamic model is capable of accurately predicting the trajectory and peak velocities of our current design. We will present designs using our model that maximize velocity. Our simulation results will be accompanied by our experimental results for various fluid loads and design parameters. These results will then be used to inform us on how the biological system operates and how the underlying physics contribute to its performance.