Reliability-Based Aerodynamic Shape Optimization of a Quadcopter

摘要

This paper presents an aerodynamic shape optimization under uncertainty approach for a quadcopter. The performance of the quadcopter is defined using the statistical moments of the required power which is a function of the drag torque on the propellers. Probabilistic constraints are applied to the lift coefficient. The probability the lift is less than the quadcopter weight is kept below a user defined value. The propeller geometry is parameterized using the ANSA software, the CFD simuladon is performed in OpenFOAM, and the post processing of the results is conducted in META software. The shape of the quadcopter geometry is parameterized using morphing boxes. A design of experiments (DOE) generates a number of design sites for the drag objective function and the lift-based probabilistic constraint. A second-order saddlepoint approximation using a quadratic response surface metamodel is used to calculate the probabilistic constraint in the reliability based design optimization. The metamodel is constructed using the DOE design sites. A gradient-based optimization algorithm carries out a robust and reliability-based design optimization using the sensitivities of the mean value and standard deviation of the drag objective function and probabilistic lift constraint with respect to the design variables. The methodology is validated with a mathematical problem and then applied to the shape optimization of a quadcopter under uncertain geometrical parameters.