Do you know how bees fly?
If you don’t, you shouldn’t feel bad, it’s a question that has puzzled scientists for years.
In fact until recently it was a mystery, but in 2006 researchers at the California Institute of Technology and the University of Nevada performed a series of experiments with high-speed cameras, live honeybees, and robotic honeybee wings that helped explain this phenomenon.
It turns out that honeybees use a unique approach to beat gravity.
Usually flying insects follow a pattern; smaller insects have smaller wings and ‘flap’ them at a higher frequency to stay aloft; larger insects tend to have larger, longer wings that they ‘flap’ at a lower frequency. Most flying insects use a large wing stroke amplitude (a angle measurement of how far the wing will move around their body during a full wing stroke). Honeybees get their lift from high frequency, low amplitude wing strokes.
They found that an unloaded bee would generally only move it’s wings at ~90º and ~230 Hz. When the bee flew in simulated load conditions, they found that the frequency stayed the same and the amplitude increased to ~130º. The robotic bee wing was programmed to mimic the wing movements of a hovering bee. When tested, the results were similar to the live bee data. It confirmed the assumption that the constant frequency wing strokes with a higher amplitude yields a wider range power output and a increased peak output on the same wing compared to having a fixed wingtip speed with variable frequencies and amplitudes.
This is important, since most flies use the second method of low frequency and high amplitude in their wing strokes. The interesting part is that the quasi-steady model developed from fruit fly wing simulations for the bee’s wing doesn’t match up with empirical data from the bee wing model. The quasi-steady force estimate predicted low forces at the beginning and end of the wing stroke. The measured forces showed unexpected peaks. Although less efficient than the fruit fly, the higher frequency and variable amplitude model allows bees to adapt to heavier flight loads (pollen, nectar, water, etc..) by having a larger range of force output, and a higher proportional peak wing force. This characteristic makes bees one of the most unique flying insects on this planet.
For more information, check out the published paper HERE