Optic Flow Based Autopilots: Speed Control and Obstacle Avoidance

  • Nicolas FranceschiniEmail author
  • Franck Ruffier
  • Julien Serres


The explicit control schemes presented here explain how insects may navigate on the sole basis of optic flow (OF) cues without requiring any distance or speed measurements: how they take off and land, follow the terrain, avoid the lateral walls in a corridor, and control their forward speed automatically. The optic flow regulator, a feedback system controlling either the lift, the forward thrust, or the lateral thrust, is described. Three OF regulators account for various insect flight patterns observed over the ground and over still water, under calm and windy conditions, and in straight and tapered corridors. These control schemes were simulated experimentally and/or implemented onboard two types of aerial robots, a micro-helicopter (MH) and a hovercraft (HO), which behaved much like insects when placed in similar environments. These robots were equipped with opto-electronic OF sensors inspired by our electrophysiological findings on houseflies’ motion-sensitive visual neurons. The simple, parsimonious control schemes described here require no conventional avionic devices such as rangefinders, groundspeed sensors, or GPS receivers. They are consistent with the neural repertory of flying insects and meet the low avionic payload requirements of autonomous micro-aerial and space vehicles.


Optic Flow Dung Beetle Forward Speed Flight Pattern Aerial Robot 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We are grateful to S. Viollet, F. Aubépart L. Kerhuel, and G. Portelli for their fruitful comments and suggestions during this research. G. Masson participated in the experiments on bees and D. Dray in the experimental simulations on LORA III. We are also thankful to Marc Boyron (electronics engineer), Yannick Luparini, and Fabien Paganucci (mechanical engineers) for their expert technical assistance and J. Blanc for revising the English manuscript. Serge Dini (beekeeper) gave plenty of useful advice during the behavioral experiments. This research was supported by CNRS (Life Science; Information and Engineering Science and Technology), an EU contract (IST/FET – 1999-29043), and a DGA contract (2005 – 0451037).


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© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Nicolas Franceschini
    • 1
    Email author
  • Franck Ruffier
    • 1
  • Julien Serres
    • 1
  1. 1.Biorobotics LabInstitute of Movement Science, CNRS & Univ. of the MediterraneanMarseilleFrance

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