Unmmaned Aerial Vehicle (UAV)
Unmmaned Aerial Vehicle (UAV)
The multirotor type unmanned aerial vehicle (UAV) are used in various fields with excellent flight stability, vertical takeoff and landing capability. As the multirotor UAV demand for technology development and commercialization is increasing rapidly, it is necessary to research and develop a design framework that is able to design the multirotor UAV according to the required missions in conceptual design phase. CLOUDS, Conceptual Layout Optimization for Universal Drone Systems, is developed for the abovementioned purpose. For the performance analysis of the multirotor, multidisciplinary analysis is conducted: weight/trim/structure/aerodynamic/electric propulsion system. Integrated with OpenMDAO developed by NASA, the design optimization is carried out for user-defined mission profile and objective functions.
To secure mission success of multirotors in outdoor flight, a 6-DOF simulation based is necessary to estimate flight performance under external wind condition. Coupling CLOUDS with cascade PID control method and 6-DOF motion analysis, flight simulation tool is developed and effect of external wind condition on flight endurance was investigated. The simulation results show that battery usage increases up to 24% according to the forward flight speed and external wind intensity, implying that the wind effect on the performance should be reflected in initial conceptual design of multirotor UAV
In the conceptual design phase, a lot of uncertainties exist due to the low level of design knowledge and high design freedom. To reduce design feedback and possibility of mission failure, Uncertainty Quantification (UQ) is necessary in conceptual design phase. For multirotor UAV, CLODUS is coupled with Monte Carlo Simulation (MCS) after identifying aleatory uncertainty in the UAV system and epistemic uncertainty in CLOUDS.
Reference
[1] Daejin Lim, Hyeongseok Kim, Kwanjung Yee, “Mission-oriented performance assessment and optimization of electric multirotors,” Aerospace Science and Technology, Vol 115, Aug. 2021.
[2] Hyeongseok Kim, Daejin Lim, Kwanjung Yee, “Flight Control Simulation and Battery Performance Analysis of a Quadrotor under Wind Gust,” ICUAS 2020, Athene, Greece, Sep. 2020