During the past few years, there has been a rise in novel fully actuated multirotor UAV configurations, each customised to perform a different task. These configurations must be optimised to extract their full potential for the different use cases. The main issue with existing optimisation methods is the computational cost required to produce a design when the optimisation includes both continuous and discrete variables, such as off-the-shelf components. We propose a hybrid optimisation method using continuous surrogate methods with localised parameter sweep. The continuous stage aims at finding the optimal value for the continuous design variables and reduces the search space for the discrete design variables. Empirical models for the off-the-shelf components are used to reduce the size of the continuous stage of the optimisation. The localised search method consists of a parameter sweep of the discrete design variables within a certain threshold of the optimal parameters from the first stage. Three case studies confirm the method’s capabilities with different configurations and optimisation setups, comparing optimality, success rate and computational cost. The optimal design from the hybrid method is consistent with the baseline methods used for comparison within each case study, with a minimum success rate of 30% while reducing cost by 98%. Compared to specialised discrete methods, the improvement in computational cost is inconsistent; however, it achieves a reduction of 99.3% with certain design requirements. A comparison to another hybrid method was also performed, with the proposed method maintaining its cost, optimality and success rate better than the SQP-DSS method when increasing method complexity.
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