**7. Conclusions**

This paper presents a rapid and robust sizing methodology, along with a comparative study on the impact of energy source configurations, on the autonomy of a multirotor aerial vehicle. The methodology focuses on selecting the optimal components for the propulsion chain of an eVTOL multirotor aerial vehicle based on a specific flight mission. The objective is to locate the optimal parameters for the propeller and motor pair, aiming to maximize the specific efficiency *ηMP*(*N*/*w*) of the propulsion chain. To achieve this, a global nonlinear optimization using the simulated annealing algorithm (SAA) is employed, with constraints placed on the propeller's diameter and pitch angle.

The optimized parameters of the propeller/motor pair allow for the sizing of the ESC and the energy storage system, ensuring that they meet the requirements of the drone's overall mission. This methodology enables the estimation of the resulting gross take-off weight *GTOW* of the propulsion chain, using mass regression models based on supplier data. The comparative study of different energy storage source configurations highlighted the potential of hybrid sources such as Bat/HFC or Bat/SC/HFC, in terms of autonomy and reliability, through the combination of multiple energy sources. As part of future work, some perspectives will be considered. On the one hand, a full-scale model of a multi-rotor

aerial vehicle will be considered, in order to take into account the aerodynamic effect of the structure on the specific efficiency. In this case, the sizing methodology validation step will be carried out on a full scale. On the other hand, the energy management part for each energy source configuration will be considered, in order to have a more global comparison in terms of the flight time, controllability, and implementation complexity of each configuration.

**Author Contributions:** Conceptualization, S.C.; methodology, S.C.; software, S.C.; formal analysis, S.C.; resources, S.C., R.S., C.M., G.K. and A.A.; writing—original draft preparation, S.C.; writing review and editing, S.C., R.S., C.M., G.K. and A.A. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Data Availability Statement:** The data are available upon request to the corresponding author, Saad Chahba: saad.chahba@estaca.fr.

**Conflicts of Interest:** The authors declare no conflict of interest.
