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edfas.org ELECTRONIC DEVICE FAILURE ANALYSIS | VOLUME 22 NO. 2 16 A BIOLOGICALLY INSPIRED APPROACH TO INTERCEPTION Frances S. Chance Sandia National Laboratories, Albuquerque, New Mexico fschanc@sandia.gov EDFAAO (2020) 2:16-21 1537-0755/$19.00 ©ASM International ® INTRODUCTION Humans throughout history have looked to biology for engineering inspiration. Perhaps one of the most famous examples is looking to birds to inspire a vehicle capable of flight. While Daedalus’s wings of wax and feathers may have only existed in Greek mythology, Leonardo da Vinci’s sketches of prospective flying machines and their resemblance to birds are well documented. This article focuses on the problem of interception, focusing on insects, specifically dragonflies, for inspiration. A number of recent studies have characterized the huntingbehaviors of animals, [1-2] reporting on a range of animals, including dragonflies, [3-5] bats, [6] hawks, [7] peregrine falcons, [8] and robber flies [1,9] that demonstrate behaviors best fit by proportional navigation guidance law. The use of pro- portional navigation by animals is particularly interesting because it is also used bymodernmissile systems, raising the question of what can be learned from understanding how an insect implements this guidance law. The ques- tion of how animals implement proportional navigation remains unanswered, however, as it requiresmaneuvering tomaintain a constant angle between the animal’s line-of- sight to its prey and an external reference. [10] Dragonflies are highly successful hunters, achieving a 90-95% success rate in nature. [11-12] While these success rates were reported under natural foraging conditions in whichdragonflieswereable to selectwhichprey topursue, they highlight the potential of the biological dragonfly systemto inspire aman-made system. Moreover, the drag- onfly interception system is attractive for study because the underlying neural circuitry is likely to be “light” (insect nervous systems are relatively simple compared to those of humans and other animals), and the technology exists to record from dragonfly brains while the dragonflies are in flight, indicating that data formodel validationwill soon be available. [13] As dragonflies hunt their prey, theymaintain the prey- image on a specific location on their eyes known as the fovea. [14] This behavior is referred to as foveation. Simply maintaining a constant angle between direction of move- ment and line-of-sight to theprey (both relative toan inter- nal reference system, for example the body’s longitudinal axis)will produce either pure classical pursuit (inwhich the pursuer heads straight at the target at all times) or deviated pursuit (in which the pursuer maintains a constant but non-zeroanglebetween the line-of-sight to thepreyandan internal reference), andby itself cannot providea complete description of how a dragonfly implements proportional navigation. This article presents a novel model of drag- onfly proportional navigation, intentionally cast in a form easily translated to a man-made vehicle or interception system. Specifically, the dragonfly model not only uses prey-image to target its prey, but also uses prey-image translation as an error signal for correcting its trajectory. MODEL The model presented here was explicitly developed for the purpose of hypothesizing how dragonflies use visual information (specifically prey-image slippage on the eye) to calculate prey-interception trajectories guided by proportional navigation. While simulating the dragonfly motor system (howwings andmuscles produce the forces required to implement the trajectory) is certainly a nec- essary effort for evaluating potential applications of this model, it is outside the scope of this project. Likewise, simulation of the dragonfly eyes also remains outside of the scope of this project, although this would be an interesting direction to pursue. The speeds of both the model dragonfly and prey are 10 m/s in all simulations presented here. While in reality dragonflies flymuch faster than their prey, 10m/s iswithin the range of a dragonfly’s capability but an order of mag- nitude faster than that of a fruit fly prey. Incorporating a