Study shows how a fly lands on a ceiling (with slo-mo video)

Today we're looking at how a fly lands upside-down – up on a ceiling – courtesy of a study published this week in the AAAS's Science Advances. Inverted landing is something a fly takes for granted – largely because, as it would appear in this study, most of this process takes place in a fraction of a second. The findings in this paper show an expanded understanding of the various biomechanical, sensory, and neural processes that take place when a fly attempts to land on a ceiling. This data could lead to fantastic future applications – let's take a look at why.

In the image you see above, we get a visual summary of maneuvers a fly initiates in order to land on a ceiling. The fly moves upward – like it normally would, legs down, head and wings up, then makes some super-quick rotational maneuvers. The key is the attachment of one or more of the fly's legs attaching to the ceiling.

Once a pair of forelegs are "firmly attached to the ceiling", the fly initiates a leg-assisted body swing, and ultimately a full multi-leg attached sort of situation – a successful landing. Because of the speed at which this relatively complex landing must take place, the potential to expand our knowledge on efficient use of limited computational power is giant.

"Our study provides critical insights on inverted landing behaviors and the underlying biomechanical, sensory, and neural processes," said researcher Pan Liu (et. al.) in the paper published this week. "It also points to possible mechanisms that can enable small-animal or robotic systems with limited computational resources to generate fast yet complex behaviors."

Above you'll see a video captured by the study – flies landing on ceilings in super-slow motion. In the video, blue bottle flies (Calliphora vomitoria), are captured using high-speed videography as they attempt to land on the ceiling of a sealed flight chamber.

This setup allowed the researchers to capture wingbeats, acceleration, linear velocity, and more. Successful inverted landings averaged approximately 4-8 wingbeats between the start of body rotation to the ventral side-up final move. It was also found that average wingbeat frequency in these successful landings was approximately 172.7 ± 7.7 Hz.

To learn more about this subject, see Science Advances, October 23, 2019, Vol. 5, no. 10, eaax1877. With code DOI: 10.1126/sciadv.aax1877 you'll find the paper "Flies land upside down on a ceiling using rapid visually mediated rotational maneuvers." This paper was authored by researchers Pan Liu, Sanjay P. Sane, Jean-Michel Mongeau, Jianguo Zhao, and Bo Cheng.