A simple model of a drive mechanism for an ornithopter I made - can be scaled printed and played around with
An ornithopter is a flying machine that uses flapping wings similar to a bird or insect to lift and propel itself
This mechanism can be used to flap 4 wings in a rythm that is energy efficient as the acceleration and deceleration of the wings is phase shifted to reduce peak torque while also keeping flight stable
wingspeed is phaseshifted 45 degrees each to minimize peak torque while direction is flipped symetrically to even out the linear momentum

Infill can be adjusted to balance weight and strength depending on the overall machines design mass.