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As a person moves about in a building, the footsteps induce the propagation of waves in the floors (especially the floor tiles), and researchers have acquired these vibrations to study several things like occupant localization, pedestrian counting, person identification, fall determination, and gait analysis. This work presents similar research but in a different species. Specifically, we show that acquiring the guided ultrasonic waves generated by a mouse’s movement can enhance the analysis of the animal’s gait. In an open-field arena fitted with ultrasonic sensors and a video camera, F os2A−iCreER (TRAP2) mice are allowed to explore and behave (one at a time). The animal’s motion is registered through video and ultrasonic recordings. As the rodent moves around the open field, its voluntary and involuntary movement applies forces to the structure the animal stands on, leading to the generation of acoustic waves. The acoustic waves propagate through the structure as Lamb and Shear Horizontal (SH) waves, which are detected by ultrasonic sensors and acquired through an amplitude threshold-based data acquisition system. With this acquisition system, waves are acquired and stored as discrete Acoustic Emission (AE) hits, each AE hit being a consequence of an animal’s movement or behavior. The time of the AE hit (which indicates the moment of a foot strike/movement) is used to get deeper insights into the animal’s locomotion. The instantaneous speed from the video recordings and the time duration between the subsequent foot strikes (obtained from the AE hits) are combined to propose a procedure for performing gait analysis in an open-field setting. This would lead to a way to not only undertake gait analysis in a free environment but also to undertake an analysis that would decrease variance in the evaluated gait parameters.
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