Optimization of a bio-inspired sound localization sensor for high directional sensitivity

Reid, Andrew; Uttamchandani, Deepak; Windmill, James F. C.

doi:10.1109/icsens.2015.7370605

Cited by 4 publications

(6 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…29 Thickness is taken from literature or directly measured on the 3D-printed samples later on. 19 Even though the sample printed has two halves of different thicknesses, it is safe to assume we can expect a similar dependence with thickness and sizes of the axes.…”

Section: Resultsmentioning

confidence: 99%

“…Mechanisms like those of Ormia or Gryllus have been discarded in Achroia grisella through x-ray scans of their bodies. 19 Moreover, females with one ear pierced were still found able to track the artificial male calls, 27 which suggests that the moths' directional hearing is in fact monoaural and dependent exclusively on the morphology of the ear.Achroia's hearing system consists of two ears that sit on the front of their abdomen next to each other. Each ear is comprised of an elliptical eardrum, with two sections of different thicknesses (the thicker one is called conjuctivum and the thinner one is called tympanum proper or tympanic membrane), and a scolopidium, a cluster of four auditory neurons that attach directly to the middle of the thin section.…”

mentioning

confidence: 99%

“…All these sections move out of phase with each other, with the main peak almost in opposition to the other two regions. 19,21…”

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Directional passive acoustic structures inspired by the ear of Achroia grisella

Díaz-García

Reid²,

Jackson³

et al. 2022

The Journal of the Acoustical Society of America

View full text Add to dashboard Cite

The need for small directional microphones is patent in the current market. From smartphones to hearing aids, a small microphone capable of rejecting ambient noise is highly desirable. Most MEMS microphones are omnidirectional and have to resort to arrays to achieve directionality, effectively counteracting the reduced size that they offer in the first place. For this reason, we use bio-inspiration and turn to nature to find examples of solutions to this problem. The female specimens of the moth Achroia grisella are capable of monoaural directional hearing, which they use to track the males’ mating calls. It is believed that they achieve directionality solely due to the morphology of their tympana. To test it, we first produce a multiphysics simulation of the structure that serves as a starting point. For experimental measurements, additive manufacturing is chosen for its ease and cost-efficiency. 3D-printed samples of the same model are examined through micro-CT scanning and then measured using laser-Doppler vibrometry to determine their frequency and directivity responses. The results of both approaches are compared, and it is found that the structure does indeed show directionality with the second eigenfrequency showing a hypercardioid-like pattern towards the front of the moth.

show abstract

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

“…All these sections move out of phase with each other, with the main peak almost in opposition to the other two regions. 19,21…”

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Directional passive acoustic structures inspired by the ear of Achroia grisella

Díaz-García

Reid²,

Jackson³

et al. 2022

The Journal of the Acoustical Society of America

View full text Add to dashboard Cite

show abstract

“…Capacitive combs, in contrast, can be fabricated in a single layer MEMS device and offers the benefits of extremely low noise [41 ,42] at the trade-off of electrical sensitivity. In recent years PZT [43][44][45] or Aluminium Nitride [46] thin film layers have been used in combination with cantilevers connecting to the diaphragms to provide an alternative method of transduction.…”

Section: First Order Ormia Inspired Microphonesmentioning

confidence: 99%

Insect-inspired acoustic micro-sensors

Reid

Windmill

2018

Current Opinion in Insect Science

Self Cite

View full text Add to dashboard Cite

Micro-Electro Mechanical System (MEMS) microphones inspired by the remarkable phonotactic capability of Ormia ochracea offer the promise of microscale directional microphones with a greatly reduced need for post-processing of signals. Gravid O. ochracea females can locate their host cricket's 5 kHz mating calls to an accuracy of less than 2 despite having a distance of approximately 500 mm between the ears. MEMS devices base on the principles of operation of O. ochracea's hearing system have been well studied, however commercial implementation has proven challenging due to the system's reliance on carefully tailored ratios of stiffness and damping, which are difficult to realize in standard MEMS fabrication processes, necessitating a trade-off between wideband operation and sensitivity. A survey of the variety of strategies that have been followed to address these inherent challenges is presented. IntroductionThe traditional method of sound source localization is to build a microphone array which combines at least two independent omnidirectional microphones [1]. Calculating the incident angle of sound waves then depends on the separating distance (i.e. time delay) between the microphones receiving the plane waves [2][3][4]. Similar to microphone arrays, many large animals including human beings have two ears with sufficient separation that the nervous system is able to resolve the interaural time difference (ITD) and interaural intensity difference (IID) to determine the source location. The requirement for spatial separation poses a fundamental problem for sound localization in small animals [5] and in micro-scale devices (i.e. Micro-Electro-Mechanic-System (MEMS) devices) smaller than the wavelength of interest.In the 1990's, O. ochracea was found to have a great capability for detecting sound source [6,7 ,8]. The parasitic female Ormia uses auditory cues to localize the mating call of a host Gryllus, a genus of cricket, and then deposits its predaceous larvae on the host [9]. The cricket's mating call has a fundamental frequency around 5 kHz and wavelength at approximately 70 mm, compared to the interaural distance of Ormia that is only around 520 mm [10,11]. Despite the extremely small distance that gives the original maximum ITD and IID as approximately 1.5 ms and 1 dB [12], respectively, experimental investigations show that it can localize the mating call with a resolution less than 2[13]. This high accuracy is attributed to the mechanical coupling structure of Ormia's ear, as shown in Figure 1(a) and (b), which enhances both ITD and IID by up to 40 times greater than the original values at 5 kHz [14 ]. The first resonance is a rocking mode about the bridge centre point, and the second is a translational mode with each end of the bridge moving in-phase while the bridge bends in the middle as shown in Figure 1(c). The response of the Ormia ear at any frequency is then described by a linear combination of these resonance modes [15 ].Ormia-inspired MEMS microphone designs can be broadly separated into two...

show abstract

Bio-Inspired Scheme of Killer Whale Hunting-Based Behaviour for Enhancing Performance of Wireless Sensor Network

Parvathi

Talanki

2020

Advances in Intelligent Systems and Computing

View full text Add to dashboard Cite

Optimization of a bio-inspired sound localization sensor for high directional sensitivity

Cited by 4 publications

References 15 publications

Directional passive acoustic structures inspired by the ear of Achroia grisella

Directional passive acoustic structures inspired by the ear of Achroia grisella

Insect-inspired acoustic micro-sensors

Bio-Inspired Scheme of Killer Whale Hunting-Based Behaviour for Enhancing Performance of Wireless Sensor Network

Contact Info

Product

Resources

About