Our experimental system studies the effects of externally controlled oscillation on directly and indirectly driven system of metronomes. This is analogous to many practical systems such as pacemaker effect on heart cells, the external light effect on the suprachiasmatic nucleus in the brain. Here the pacemaker can be compared to an external driving force to the system where the heart cells are our oscillating system. Also, in the suprachiasmatic nucleus cell system, the external input is external light which synchronizes the cell. We explore the synchronization of directly and indirectly driven metronomes due to externally provided forcing.
We designed an experimental setup to closely replicate the experimental system constructed by Martens et al. The system consists of 3 platforms which contain 4 metronomes each. Each metronome and platform have UV sensitive dots which shines in dark room with UV light over it. This allows us to analyze the metronome motion using the video analysis toolbox of Matlab. Our video analysis code can compute the phases of metronomes and platforms which help us to qualitatively examine the system. We drive our system via a servo motor which is connected to the middle platform with an arm designed to reduce friction. The servo motor has a built-in feedback mechanism and its input is controlled via a PID controller to give sinusoidal input to the platform.
We observe in our experiments that when the metronomes are directly driven, and the driving frequency is within +-3% of metronomes frequency, the metronomes Kuramoto order is near unity i.e. the metronomes synchronize. We observe that when the driving frequency is similar to metronomes placed on the indirectly driven platform, metronomes on indirectly driven platform synchronize. While at the same time if driving frequency is different than metronome on the directly driven platform, metronomes on directly driven do not synchronize.
Our experiments show that in order for a pacemaker to synchronize the oscillating system, the frequency of input should be similar as systems one is seeking to synchronize. This suggests that for example if we want to synchronize certain cells of the heart while not affecting other, the pacemaker input should match the target cells frequency.
Metronome, Synchronization, external driving
Level of Degree
Electrical and Computer Engineering
First Committee Member (Chair)
Dr Francesco Sorrentino
Second Committee Member
Dr. Rafael Fierro
Third Committee Member
Dr. John Russell
Chhabria, Sumit. "Synchronization in an externally driven mechanical oscillators experiment." (2018). https://digitalrepository.unm.edu/ece_etds/415