# Improvement of Hexacopter UAVs Attitude Parameters Employing Control and Decision Support Systems
## 6 Conclusions and Future Work  
This study was conducted employing two hexacopter variants in which the sensor system was analysed and synchronized so that the drone's performance in stationary fixed-point flight was continuously improved. The flight parameters extracted from the tests  
Figure 44: Hexacopter impact during field tests. Figure 43: Drop test results at 0.1s after the impact. were analysed, and the necessary corrective measures were taken accordingly to verify if the platform operates at optimal parameters, but also for stationary flight manoeuvres at hover, in average atmospheric conditions: temperature of 10-30\({}^{\circ}\), 1-2 m/s wind and no precipitation. The peculiarity of this work lies in the combination of experiments (both in the laboratory and in situ) with the FEM analysis in an original approach. The study also involved the development of a mathematical model for analytical calculation, not included in the paper, to determine the aerodynamic performance, as well as the verification of the solution of the hexacopter platform architecture. Only excerpts from the analytical computation were included in the discussion of the CFD simulation results for comparison purposes. Test outcomes were assessed, and conclusions regarding the numerical results were synchronized with the experimental ones. Regarding the hexacopter frame, it may be concluded that having a smaller distance between the rotors can improve the aerodynamic performances of the hexacopter by increasing the interference between the propellers. Similarly, the effects of interference between propellers are progressively reduced with the increase in rotor positioning. Thus, the homogeneity of the distribution of the airfoils and the shape and symmetry of the vortex are essential conditions for the hexacopter to generate better lift forces. These must be deeply understood in the sense that the simulation required to create flow domains may result in values slightly lower than the experimental, real values. FEM simulations are essential for achieving the aerodynamic stability and ensuring low power consumption and stable flight behaviour at high wind speeds, as well as achieving the ability of the vehicle to carry high payloads and increased operational areas of the hexacopter. These are mandatory requirements when launching a new, powerful hexacopter on the market. The simulation study can be continued by considering the hexacopter speed during manoeuvres and adjusting the rotational speeds of the propellers according to the experimental data. The experiments completed employing the online platforms revealed a major drawback regarding the accuracy of the provided data. The deviation margin in respect to the real values was around \(\pm\)15%; thus, when making the configurations and integrating the components, this error margin must be considered by choosing high-quality components and sensor systems to compensate this value. The data extracted from sensors mounted on the drone illustrated good results in terms of altitude, attitude, GPS, vibrations, response of the motors, temperature, atmospheric pressure and ESC readings, respectively. The hexacopter parameters acquired during hover flight allowed the remark regarding the accelerometers' behaviour that they are not significantly affected by vibration during operation. Further adjustments to the current hexacopter-mounted sensors are underway to achieve even better results in terms of altitude and attitude estimation, positioning error compensation, engine control and command, telemetry data transmission, video signal transmission and radio interference compensation. Work regarding adding other sensors such as anemometers, LIDAR, acoustics and IR cameras is also in progress. Today, BVLOS is of major importance; thus, a variant of the BVLOS sensors kit is currently under development and will be mounted and tested on the hexacopter. Conceptualization, M.-A.S. and C.P. ; Data curation, C.-E.M.; Formal analysis, F.-A.N. ; Funding acquisition, M.-A.S.; Investigation, M.-A.S. and C.P.