Development of a Whale-Shark-Inspired Gliding Robotic Fish With High Maneuverability

In this article, we present the design and implementation of an innovative bioinspired gliding robotic fish and a gliding angle controller. Through mimicking a whale shark, the gliding robotic fish is designed with diversified control surfaces and a streamlined shape instead of the conventional wings with large wingspan aiming at both high maneuverability and distinguished gliding performance. The mechatronic design of the whale-shark-inspired gliding robotic fish is first provided. A dynamic model for gliding motion is established and the hydrodynamic analysis is performed via computational fluid dynamics simulation. The effects of both the deflection of the pectoral fins and the displacement of the movable mass on the gliding motion are analyzed. Then, based on the model and the analysis, a gliding angle control strategy is constructed via the backstepping methodology and the sliding mode methodology, aiming at the robustness of the control system to unknown perturbation. Afterward, a control allocation law is designed and solved by the Newton method. Simulations are conducted to evaluate the effectiveness of the proposed controller. Experiments are also executed to verify the dynamic model and illustrate the remarkable motion capability of the newly developed robot prototype. The results of this article supply clues to the improvement of the locomotive ability for the gliding robotic fish in both shape design and motion control.