The fluid mechanics of small-scale locomotion has recently attracted considerable attention, due to its importance in cell motility and the design of artificial micro-swimmers for biomedical applications. Most studies on the topic consider the ideal limit of zero Reynolds number. In this paper, we investigate a simple propulsion mechanism --an up-down asymmetric dumbbell rotating about its axis...

The objective of this lecture is to review the basic building blocks of lumped parameter rotational mechanical systems and to build the foundations that will enable you to model more complex dynamic systems consisting of translation and rotational elements. Corresponding to the translational elements mass, spring and damper, are the rotational inertia, rotational spring and rotational damper, r...

Large-scale deployment of Renewable Energy Sources (RES) has led to significant generation shares of variable RES in power systems worldwide. RES units, notably inverterconnected wind turbines and photovoltaics (PV) units that do not provide rotational inertia, are effectively displacing conventional generators and their rotating machinery. This has implications for frequency dynamics and power...

This study presents analysis of errors of calculations for engine load during vehicle acceleration phase, resulting from some simplifications or errors in selection of mass moment of inertia. A varied impact of the assumed, on unknown basis, values of the mass moments of inertia on calculation error was shown. According to the author, more accurate results of calculations of coefficient of rota...

INTRODUCTION Inverted pendulum models have been very beneficial for the modeling and analysis of human gait and balance [Kuo, 2007]. These reduced models allow us to ignore the movements of the individual limbs, and instead, focus on two important points -the center of pressure (CoP) and the center of mass (CoM) -and the lean line that connects the two points. A limitation of the existing reduc...

Humans and humanoid robots are often modeled with different types of inverted pendulum models in order to simplify the dynamic analysis of gait, balance and fall. We have earlier introduced the Reaction Mass Pendulum (RMP), an extension of the traditional inverted pendulum models, which explicitly captures the variable rotational inertia and angular momentum of the human or humanoid. In this pa...

Using the concept of tunneling two level systems we explain the reduction of rotational inertia of disordered solid He observed in the torsional oscillator experiments. The key point is a peculiar quantum phenomenon of momentum deficit for two level systems in moving solids. We show that an unusual state which is essentially different from both normal and superfluid solid states can be realized...