Short granular chain under vibrations: ratcheting and transitions
JC Tsai / 蔡日強1*, 孫宇岑1,2, 林蔚廷 林昱辰 張繼中 彭治維1, 黃仲仁2, 阮文滔1
1Institute of Physics, Academia Sinica, Taiwan
2Dept. of Physics, National Taiwan Normal University, Taiwan
* presenting author:JC Tsai, email:jctsai@phys.sinica.edu.tw
We report our studies on the behaviors of a short granular chain under vibrations. Our first set of experiments with a spatial gradient of vibration have demonstrated the change of ratcheting dynamics from slow monotonic creeping against the gradient, to rapid stochastic head swinging with a reversed bias in its direction, and to seemingly random fluctuations. This spatial pattern suggests bifurcations of the state of the chain, whereas the reversed ratcheting reflects an interesting dialogue between the size of the object and the spatial gradient [Ref: Phys. Rev. Lett. 112, 058001 (2014) ]. In addition, we use counterpart experiments with uniform vibrations to characterize both the macroscopic and the microscopic states of the chain and, in particular, the spontaneous switch of behaviors in the transitional amplitudes of vibration.


Keywords: granular chain, ratcheting, transition