Today, robots and unmanned aerial vehicles are being used extensively in modern societies. Due to a wide range of applications, it has attracted much attention among scientists over the past decades. This paper deals with the problem of the stability of a four-rotor flying robot called quadrotor, which is an under-actuated system, in the presence of operator or sensor failures. The dynamica...

Low frequency power oscillations may be triggered by many events in the system. Most oscillations are damped by the system, but undamped oscillations can lead to system collapse. Oscillations develop as a result of rotor acceleration/deceleration following a change in active power transfer from a generator. Like the operations limits, the monitoring of power system oscillating modes is a releva...

The simulation of wind turbine rotor aerodynamics can be improved upon by increasing the physics content in the underlying approximations. The current effort is targeted at an aerodynamics model in which the flow field is decomposed into two domains. The inviscid external flow domain is modeled with a “panel method” type of flow solver and the viscous regions are modeled with an integral bounda...

We analyze the dynamics of rotary biomotors within a simple nanoelectromechanical model, consisting of a stator part and a ring-shaped rotor having 12 proton-binding sites. This model is closely related to the membrane-embedded F0 motor of adenosine triphosphate (ATP) synthase, which converts the energy of the transmembrane electrochemical gradient of protons into mechanical motion of the rotor...

Abstract: A novel dynamic co-simulation methodology of overall wind turbine systems is presented. This methodology combines aerodynamics, mechanism dynamics, control system dynamics, and subsystems dynamics. Aerodynamics and turbine properties were modeled in FAST (Fatigue, Aerodynamic, Structures, and Turbulence), and ADAMS (Automatic Dynamic Analysis of Mechanical Systems) performed the mecha...

The reorientational relaxation of molecular systems is important in many phenomenon and applications. In this paper, we explore the reorientational relaxation of a model Brownian rotor lattice system with short range interactions in both the high and low temperature regimes. In this study, we use a basis set expansion to capture collective motions of the system. The single particle basis set is...

Title of dissertation: CONTRIBUTIONS TO THE DYNAMICS OF HELICOPTERS WITH ACTIVE ROTOR CONTROL Carlos A. Malpica Doctor of Philosophy, 2008 Dissertation directed by: Professor Roberto Celi Department of Aerospace Engineering This dissertation presents an aeromechanical closed loop stability and response analysis of a hingeless rotor helicopter with a Higher Harmonic Control (HHC) system for vibr...

In this paper a roll-walking motion of a robot with a multi-rotor drive system is considered. The robot represents a rigid body with the multi-rotor drive system which consists of pairs of conjugate rotors located on the main axes. The multi-rotor drive system allows using conjugate spinups and captures of conjugate rotors to perform roll-walking motion of the robot. To perform a single step of...

In this article, turbulent flow heat transfer in the air gap between rotor and stator of a generator under nonhomogeneous heat flux is studied experimentally. The rotor consists of four symmetrical triangular grooves. The stator surface is smooth and does not include any grooves. The relative heat flux between the rotor and the stator is 1 to 3. Temperature and heat flux are measured locally at...