Development of a micro-exciter to mimic insect vibration signals and the effect of the substrate on the playback response

In bioassays that involve the playback of recorded insect vibration signals using conventional commercial shakers, two issues need to be addressed. First, common shaker systems do not have the capability of producing insect excitations that are in the micro or milli Newton range. Second, recorded insect signals are the response of the substrate excited by the vibrations produced by the insect, but the influence of the substrate is rarely considered by the biotremology community. Here, we, therefore, present the development of a micro-excitation system across three stages: (1) an initial Arduino-based with a piezoelectric beam element; (2) a Raspberry Pi-controlled piezoelectric buzzer with fast-acting amplification circuit, compared to commercial stacked piezo actuators; and (3) an in-house developed microactuator consisting of a microcontroller and a piezoelectric actuator (MiAC-S). The evolution of the amplification circuit and its integration into MiAC-S will be described. The MiAC-S will be validated. Finally, we demonstrate the effect of the substrate on the playback of an impulse response signal compared to using a direct impulse as an excitation signal. The results indicate that the vibration response should not be used for playback of insect signals on substrates as it produces results inconsistent with theoretical expectations, thereby increasing the uncertainty and reducing the control quality of bioassays.