A Multispectral Backscattered Light Recorder of Insects’ Wingbeats

• Main Authors: Iraklis Rigakis, Ilyas Potamitis, Nicolaos-Alexandros Tatlas, Ioannis Livadaras, Stavros Ntalampiras
• Format: Article
• Language: English
• Published: MDPI AG 2019-03-01
• Series: Electronics
• Subjects: Fresnel lens; wingbeat; insects; optoelectronics; bees; wasps; fruit flies; e-traps
• Online Access: http://www.mdpi.com/2079-9292/8/3/277

Most reported optical recorders of the wingbeat of insects are based on the so-called extinction light, which is the variation of light in the receiver due to the cast shadow of the insect’s wings and main body. In this type of recording devices, the emitter uses light and is placed opposite to the receiver, which is usually a single (or multiple) photodiode. In this work, we present a different kind of wingbeat sensor and its associated recorder that aims to extract a deeper representational signal of the wingbeat event and color characterization of the main body of the insect, namely: a) we record the backscattered light that is richer in harmonics than the extinction light, b) we use three different spectral bands, i.e., a multispectral approach that aims to grasp the melanization and microstructural and color features of the wing and body of the insects, and c) we average at the receiver’s level the backscattered signal from many LEDs that illuminate the wingbeating insect from multiple orientations and thus offer a smoother and more complete signal than one based on a single snapshot. We present all the necessary details to reproduce the device and we analyze many insects of interest like the bee Apis mellifera, the wasp Polistes gallicus, and some insects whose wingbeating characteristics are pending in the current literature, like Drosophila suzukii and Zaprionus, another member of the drosophilidae family.