Bio-inspired active amplification in a MEMS microphone using feedback computation

Auditory signal processing relies on feedback mechanisms between mechanical and electrical systems that work together to enhance acoustic conditioning. In this paper a nonlinear amplification mechanism in the mosquito's auditory system is exploited as a model of inspiration. An acoustic system that provides active amplification of sound was developed using feedback computation integrated with a MEMS microphone to implement the concept. Experimental results generated by a purpose-built embedded system show signal amplification and hysteresis which replicate the response shown by the biological mosquito’s hearing system as a function of input sound intensity

Enhancing acoustic sensory responsiveness by exploiting bio-inspired feedback computation

Engineering acoustic sensors and systems that can be sensitive to small sound levels even when immersed by background noise may require out-of-the-box thinking. Biology can provide inspiration for that, allowing the engineering landscape to borrow interesting ideas and thus solve current human problems. Biological sensor and system designs are a result of many million years of evolutionary processes, which make them very-power efficient and well-adapted to perform their function in a living organism. This paper presents a theoretical study of a bio-inspired signal processing concept. The assumption is that by exploiting feedback computation between a front-end acoustic detector and a back-end neuronal based processing, the overall acoustic responsiveness of a sensory system can be controlled and enhanced to target signals of interest. Here, two methods of feedback signal entrainment are compared namely 1:1 and 2:1 resonance modes

Review of the applications of principles of insect hearing to microscale acoustic engineering challenges

When looking for novel, simple, and energy-efficient solutions to engineering problems, nature has proved to be an incredibly valuable source of inspiration. The development of acoustic sensors has been a prolific field for bioinspired solutions. With a diverse array of evolutionary approaches to the problem of hearing at small scales (some widely different to the traditional concept of "ear"), insects in particular have served as a starting point for several designs. From locusts to moths, through crickets and mosquitoes among many others, the mechanisms found in nature to deal with small-scale acoustic detection and the engineering solutions they have inspired are reviewed. The present article is comprised of three main sections corresponding to the principal problems faced by insects, namely frequency discrimination, which is addressed by tonotopy, whether performed by a specific organ or directly on the tympana; directionality, with solutions including diverse adaptations to tympanal structure; and detection of weak signals, through what is known as active hearing. The three aforementioned problems concern tiny animals as much as human-manufactured microphones and have therefore been widely investigated. Even though bioinspired systems may not always provide perfect performance, they are sure to give us solutions with clever use of resources and minimal post-processing, being serious contenders for the best alternative depending on the requisites of the problem