Presented at the American Helicopter Society Vertical Lift Aircraft Design Conference, San Francisco, CA. Copyright © 2000 by the American Helicopter Society, International. All rights reserved. Abstract This paper describes the development of a centimeterscale rotorcraft for use as an atmospheric sensor platform. The aerodynamic design of the rotor system is highlighted, while approaches to fa...

We present a dynamics model of rotor blades for real-time helicopter simulation. Collisions between the air flow and the moving blades make helicopters fly. In aerodynamics, or even in computer simulations, they precisely analyzed the collisions between the fluid(air) and the solid object(blades), and calculated the differential equations from the collisions. Thus, it was hard for them to gener...

The effectiveness of surrogate modeling of helicopter vibrations, and the use of the surrogates for optimization of helicopter vibration are studied. The accuracies of kriging, radial basis function interpolation, and polynomial regression surrogates are compared. In addition, the surrogates for the vibratory hub shears and moments are used to generate an objective function which is employed in...

Quad-rotor helicopter is an Unmanned Aerial Vehicle (UAV), whose lift is generated by four rotors located on the corner of X-shape. Due to simplicity of its dynamics and its ability to hover, quadrotor helicopter becomes as a popular platform for UAV. Current designs mostly consider a linear model for controller design. In this paper, we derivate nonlinear dynamic equations of the quadrotor UAV...

The problem of helicopter parameter estimation and blade number selection is addressed. The parameters are estimated based on Maximum Likelihood methods, and the corresponding Cramér-Rao bounds are derived. To avoid ambiguities in blade number estimation, we apply information theoretic criteria for blade number selection incorporating alternate penalty functions. We assume that a clutter filter...

The purpose of this paper is to present the development of a simple turbulence representation suitable for helicopter dynamic simulation, stability and performance analysis, as well as pilot-in-the-loop rotorcraft handling qualities assessment. The frozen field hypothesis and linear approximation are assumed. Components of the uniform field velocity are included as additive perturbations affect...

The Active Vibration and Noise Reduction (AVINOR) aeroelastic simulation code for helicopter rotor blades is described. AVINOR is a research code that has been developed at UCLA and the University of Michigan for the purpose of conducting computationally efficient aeroelastic response analyses while maintaining a level of fidelity so as to be suitable for preliminary design of helicopter rotor ...

Title of dissertation: DESIGN AND PERFORMANCE PREDICTION OF SWASHPLATELESS HELICOPTER ROTOR WITH TRAILING EDGE FLAPS AND TABS Jaye Falls, Doctor of Philosophy, 2010 Dissertation directed by: Professor Inderjit Chopra Department of Aerospace Engineering This work studies the design of trailing edge controls for swashplateless helicopter primary control, and examines the impact of those controls ...

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An approximate numerical mthod is presented for analysis and determination of modal characteristics in straight, pretwisted non-unifom helicopter blades. The analysis considers the coupled flapwise bending (out of plane), chordwise bending (in plane), and torsion vibration of both rotating and non-rotating blades. The proposed method is based on the integral expansion of Green functions (struct...