As an effort to explore the potential implementation of wing feather separation and lead-lagging motion to a flapping
wing, a biomimetic flapper with separable outer wings has been designed and demonstrated. The artificial wing feather
separation is implemented to the biomimetic wing by dividing the wing into inner and outer wings. The features of
flapping, lead-lagging and feather separation of the flapper are captured by a high-speed camera for evaluation. The
performance of the biomimetic flapper with separable outer wings is compared with that of a flapper with inseparable
outer wings in terms of lift and thrust production. For low flapping frequency ranging from 2.47 Hz to 3.90 Hz, the biomimetic flapper shows higher thrust and lift generation capability, which is demonstrated from a series of experiments. The experiments show that the outer parts of the separable wing are able to deform largely resulting smaller amount of drag production during upstroke, while still producing relatively larger lift and thrust during downstroke.