Objectives Aiming at the bottleneck of the insufficient electric endurance of unattended vehicles, the configuration design, motion performance and energy capture efficiency analysis of a manta ray bionic unmanned underwater vehicle (UUV) are carried out.

Methods The configuration of a multi-module bionic long-endurance manta ray UUV is proposed, and its motion and energy capture mechanism are deduced and obtained under the principle of wave energy capture by a floating hydraulic cylinder. Next, based on the multi-module floating body theory and three-dimensional potential theory, hydrodynamic calculation and analysis are carried out, and the motion response and wave energy capture law of the multi-module manta ray UUV are revealed under different wave directions and different connected stiffness and damping of the UUV.

Results Finally, the wave energy capture efficiency of the multi-module manta ray UUV in waves is studied in combination with the optimal stiffness and damping of the hydraulic cylinder.

Conclusions It is concluded that the wave energy capture characteristics of a multi-module manta ray UUV can be analyzed by its motion equations and energy capture formula.