Fascinating. Dragonfly Trick Makes Missiles Harder to Dodge:
A future generation of anti-aircraft missiles could be made far harder to dodge by a guidance system inspired by the flight of dragonflies and hoverflies. The missiles will mimic a strategy called motion camouflage, which predatory insects use to trick prey into thinking they are stationary.
Insects that use this technique sneak up on their prey in a way that makes them seem stationary even though they are in fact moving closer. They do this by keeping themselves positioned between a fixed point in the landscape and their prey.
It has long been suspected that male dragonflies and other flying insects use this technique during aerial battles, and this has recently been confirmed (New Scientist print edition, 7 June).
Akiko Mizutani and Mandayam Srinivasan of the Australian National University in Canberra used two video cameras to track duelling dragonflies and worked out the trajectories they used on attack runs. They found that they do indeed adjust their flight paths to appear stationary.
The remarkable thing, says Anderson, is that these complex trajectories can be worked out by a neural network computer program based only on the movement of the target as seen from the viewpoint of the missile. There is no need for sensors to keep track of the fixed spot. “You can train a system to estimate its relative position without giving it 360-degree vision,” says Anderson.
“If you put multiple missiles behind one another on the same motion camouflage trajectory, only the very first missile would be picked up by radar or infrared.” The target would never know how many missiles were behind the first one.
The technology could also be used to outfox heat-sensors. A missile could detach and explode its rear stage a small distance from the target, creating a backdrop of infrared radiation. Then the rest of the missile would continue on a motion camouflage trajectory against this noisy backdrop, making heat sensors effectively blind to it. “It’d be like coming out of the Sun,” says Anderson.