Numerical study on the effect of trajectory pattern on hovering flight

A systematic aerodynamic analysis for the wing of a micro flying robot hovering with different kinematics at a Reynolds number of 140 is carried out through the numerical solution of the two-dimensional time-dependent incompressible Navier-Stokes equations. Special attention is paid to the effect of the stroke trajectories on the aerodynamic forces and vortex shedding mechanism of the hovering wing. Six types of trajectory are selected which are line, oval, inverse-oval, eight, inverse-eight and double-eight, and for each case a harmonic hovering pattern is examined. In addition, the fruitfly hovering trajectory is also analyzed. A quantitative comparison of the aerodynamic forces and vortex structure between different trajectories is present. The simulation results reveal that the varied trajectory pattern results in significant differences in vortex structure around the wing, which indicates that an appropriate stroke deviation can be used to steer the maneuverable performance of the micro flying robot.