Discrete optimization design for a cabin-skeleton coupling structure of blended-wing-body underwater glider

Abstract

Objectives The blended-wing-body underwater glider cabin-skeleton coupling structure is optimized by using a data-driven discrete optimization idea. Methods Firstly, a Kriging-assisted discrete global optimization algorithm (KDGO) is proposed for computationally intensive black-box problems. The KDGO uses a novel infill-sampling strategy to capture discrete sample points with better performance. In the infill-sampling strategy, a multi-start method with data mining strategy is introduced, including multi-start optimization, projection, sampling, and selection. Secondly, the parametric skeleton-cabin coupling structure model was established and was analyzed by finite element in the lifting deformation and deep-water pressure conditions. Then, take the float-to-weight ratio and the strength and stability of the skeleton-cabin structure as the as the goal and constraints, respectively. Meanwhile, considering the interference between shape and cabin and the coupling relationship between skeleton and cabin, then establish a discrete optimization mathematical model of the overall coupling structure. Finally, the discrete optimization algorithm and coupling structure simulation are combined to build an overall optimization framework. Results By using KDGO to conduct 200 function evaluations and comparing the optimal feasible point in DoE with the global optimal feasible point after optimization, it was found that the optimized float-to-weight ratio of the coupling structure increased by nearly 40%, and satisfactory results were obtained. Conclusion The research results can provide a reference for the cabin-skeleton coupling structure design of blended-wing-body underwater glider.