Rotating potential of a stochastic parametric pendulum
Abstract
The parametric pendulum is a fruitful dynamical system manifesting some of the
most interesting phenomena of nonlinear dynamics, well-known to exhibit rather
complex motion including period doubling, fold and pitchfork bifurcations, let alone
the global bifurcations leading to chaotic or rotational motion. In this thesis, the
potential of establishing rotational motion is studied considering the bobbing motion
of ocean waves as the source of excitation of a
oating pendulum. The challenge
within this investigation lies on the fact that waves are random, as well as their
observed low frequency, characteristics which pose a broader signi cance within the
study of vibrating systems. Thus, a generic study is conducted with the parametric
pendulum being excited by a narrow-band stochastic process and particularly,
the random phase modulation is utilized. In order to explore the dynamics of the
stochastic system, Markov-chain Monte-Calro simulations are performed to acquire
a view on the in
uence of randomness onto the parameter regions leading to rotational
response. Furthermore, the Probability Density Function of the response
is calculated, applying a numerical iterative scheme to solve the total probability
law, exploiting the Chapman-Kolmogorov equation inherent to Markov processes. A
special case of the studied structure undergoing impacts is considered to account for
extreme weather conditions and nally, a novel design is investigated experimentally,
aiming to set the ground for future development.