Archive for April 12th, 2012

Learning from Nature robotic motion control laws

Thursday, April 12th, 2012 by Antonio Manzalini

Have you ever asked yourself how birds play their extraordinary ability to fly, at speed, through environments with several obstacles (e.g. in a forest) ?

While flying, birds have to see obstacles and control their movements to avoid collisions, pursuing, at the same time, their route planning towards a target. Seen from traditional control theory, this is an hard task, even from a computation perspective. Actually, this is an interesting and challenging problem for engineers to develop robotic motion control laws.

Well, Nature solved it in a very simple way, by adopting a different perspective.

How birds can fly at speed through environments with several obstacles ?

In fact, Researchers at Boston University have revealed the secrets behind this extraordinary capability of birds. In this paper they argue that flying animals makes use of a relatively simple “algorithm”: the basic idea is to think of the field of view of the bird, not as a set of discrete objects at different distances, but as a moving array of points: the rate of movement depends on factors such as the size and distance of objects as well as the speed of flight. With this assumption, optics of eyesight simplifies the control task: the rate of change of the object’s image size on the eyeball retina determines the time to impact. This is like to say that no “complicated” knowledge of objects’ sizes, distances or even of speed is required (or has to be processed). That’s something that can be done with direct feedback from the optical system in a highly efficient way.

This is a fascinating result which could allow the development of relatively simple algorithms and control laws to navigate an environments with obstacles by simply using image data feedbacks.

I see interesting opportunities for developing autonomous systems.