Avoiding obstacles while intercepting a moving target: A miniature fly's solution

Samuel T. Fabian, Mary E. Sumner, Trevor J. Wardill, Paloma T. Gonzalez-Bellido

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


The miniature robber fly Holcocephala fusca intercepts its targets with behaviour that is approximated by the proportional navigation guidance law. During predatory trials, we challenged the interception of H. fusca performance by placing a large object in its potential flight path. In response, H. fusca deviated from the path predicted by pure proportional navigation, but in many cases still eventually contacted the target. We show that such flight deviations can be explained as the output of two competing navigational systems: Pure-proportional navigation and a simple obstacle avoidance algorithm. Obstacle avoidance by H. fusca is here described by a simple feedback loop that uses the visual expansion of the approaching obstacle to mediate the magnitude of the turningaway response. We name the integration of this steering law with proportional navigation 'combined guidance'. The results demonstrate that predatory intent does not operate a monopoly on the fly's steering when attacking a target, and that simple guidance combinations can explain obstacle avoidance during interceptive tasks.

Original languageEnglish (US)
Article numberjeb243568
JournalJournal of Experimental Biology
Issue number4
StatePublished - Feb 2022

Bibliographical note

Funding Information:
This work was funded by the Air Force Office of Scientific Research (FA9550-15-1-0188 to P.T.G.-B and FA9550-18-1-0339 to P.T.G.-B. and T.J.W.). An Isaac Newton Trust/Wellcome Trust ISSF/University of Cambridge Joint Research Grant (097814/ Z/11/Z) to P.T.G.-B., and a Biotechnology and Biological Sciences Research Council David Phillips Fellowship (BB/L024667/1) to T.J.W. Open Access funding provided by Imperial College London. Deposited in PMC for immediate release.

Publisher Copyright:
© 2022. Published by The Company of Biologists Ltd.


  • Flight
  • Insect
  • Navigation
  • Predation

PubMed: MeSH publication types

  • Journal Article
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.


Dive into the research topics of 'Avoiding obstacles while intercepting a moving target: A miniature fly's solution'. Together they form a unique fingerprint.

Cite this