Design and experiment of a crawling-inchworm-type self-tuned dynamic vibration absorber based on silicone gel materials

Based on the different body configurations caused by varying head-to-tail distances exhibited by crawling inchworms during locomotion, this paper proposes a crawling-inchworm-type self-tuned dynamic vibration absorber (DVA) based on silicone gel materials for reducing low-frequency vibration. The proposed DVA was designed and developed by employing a magnetic hanging design with movable features, a span adjustment design with an embedded stepper motor, and a real-time control design using a microcontroller. First, a finite element simulation model was established to analyze the main structure of the self-tuned DVA using the finite element method. The frequency-shifting characteristics of the absorber were obtained by identifying the actuating modes that are sensitive to the hanging span. Second, based on the frequency-shifting characteristics of the self-tuned DVA, an absorber control system was designed by introducing a short-time Fourier transform and PID algorithm to achieve autonomous frequency adjustment of the DVA. Finally, the self-tuned absorption effects of the prototype self-tuned DVA were tested through a series of experiments, which confirmed its excellent self-tuned vibration absorption capability within the low-frequency range.