Synchronization plays an important role in some essential functions of living systems. The Kuramoto model, which is a well-known theory for describing synchronization, mathematically demonstrates the phenomenon called synchronization transition, in which synchronous and asynchronous states abruptly switch depending on the changes in the specific parameter. The experimental reproduction of the synchronization transition can enable the realization of bioinspired systems that output the sum of multiple synchronized oscillations as a large signal through a simple control mechanism, such as a switch. The Belousov-Zhabotinsky (BZ) gel is a candidate for the reproduction. It periodically deforms because of the oscillatory BZ reaction without external stimuli. From this characteristic, the BZ gel can be utilized to develop novel soft robots. However, the small deformation amplitude due to the chemical heterogeneity in a large gel and the high degree of freedom due to the chemical and gel properties make it difficult to develop and control BZ gel robots. To solve these problems, we focus on the synchronization of the BZ gels, which can lead to the simple control of large deformations of the collective gels. In this study, we theoretically model a system in which a plate is placed on multiple BZ gels arranged in a planar manner, and the plate is connected to a movable ceiling via a spring. Numerical calculations show that the synchronization and asynchronization of the BZ gels can be easily switched by changing the ceiling displacement. © 2025 IEEE.

Stimuli-responsive gels are the polymer gels whose volume is varied according to environmental conditions. It has been reported that stimuli-responsive gels with an inhomogeneous structure exhibit faster volume changes than gels without such structures. It is understood as a difference in the transfer dynamics of the solvent, though, there are few models for discussing the effect of inhomogeneity explicitly. In this paper, we propose a simple model for the kinetics of volume change by introducing inhomogeneity as the probability distribution of a random variable that characterizes the structure. Under this framework, we demonstrate that inhomogeneity actually increases the rate of volume change.