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Future Challenges Naval Engineering Education Consortium, and the Despite decades of hard work, it still appears as if research Office of Naval Research.
on the biosonar system of bats has only scratched the
surface. Many critical aspects of how bat biosonar References
functions in the animal’s complex natural environments remain, literally, shrouded in darkness. However, ever- improving recording and data-analytics technologies are likely to not only keep the flow of new insights from bat biosonar going but also to accelerate it. Based on this increasing flow of information, the future evolution of bat robots is likely to make a multitude of improvements to all aspects of biomimetic sonar function.
In the course of bat robot evolution so far, the encoding of sensory information has received the most attention. With the ongoing deep-learning revolution, there is hope that the information extraction stages of the bat robots will be able to undergo a rapid evolution in coming years.
However, neglecting the encoding stage in this endeavor could quickly lead down an evolutionary dead-end road. This is because encoding of sensory information is a
necessary precondition for being able to extract it. If this is taken into account, the future evolution of bat robots could lead to more sophisticated approaches to tackle the problems of encoding and extracting sensory information jointly instead of one at a time. This would be just one example of system-level integration where approaches designed to make a bat robot be more than the sum of its parts. Other examples for this can be found in the coordination of noseleaf and pinna motions where bats are known to have a tight coupling between the dynamics of the emission and reception interfaces (Zhang et al., 2019). With regard to all of these and many other aspects, research on bat biosonar continues to produce new and unexpected insights that are likely to fuel the evolution of bat robots for decades to come. If the insights from bat biosonar can be transitioned to engineering successfully, the pinnacle of the evolution of bat robots could be an autonomous drone that flies effortlessly through a dense forest just like many millions of bats have done every night for the many millions of years in their evolution.
Acknowledgments
The research on bat robots was supported by the Army Research Office, the National Aeronautics and Space Administration, the National Science Foundation, the
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