Quad-rotors have been a very popular topic for research in the current literature because of its capability to perform different tasks autonomously. This paper focuses on the modeling of a quad-rotor aircraft dynamics based on experimental data. It will be demonstrated that a linear model could represent its dynamics despite of quadrotor's strong nonlinearities. Also, it will be shown how a qua...

The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. ABSTRACT This paper investigates the dynamics of the SMART rotor, and presents a method to design a gain-scheduled controller to reduce the harmonic vibration throughout the flight envelope. The dynamics of the SMART rotor was examined at various flight conditions through nonli...

Abstract Based on detail analyzed optimization model of rotor dynamics of aeroengine multi-rotors system, the sum of weight of normal distribution membership function of fuzzy theory was used to describe the distribution of multi-order critical rotor speeds versus multi in common used operating speeds, and then to formulate the optimal objective function. According to the design specification a...

An asymmetric mechanism for correlated motion occurring in noninteracting pairs of adjacent orthogonal 1,4-bis(carboxyethynyl)bicyclo[1.1.1]pentane (BCP) rotators 1 in the solid state is unraveled and shown to play an important role in understanding the dynamics in the crystalline rotor, Bu4N+[1-]·H2O. Single crystal X-ray diffraction and calculation of rotor-rotor interaction energies combined...

The paper proposes a methodology for reliable design and maintenance of wind turbine rotor blades using a condition monitoring approach and a damage tolerance index coupling the material and structure. By improving the understanding of material properties that control damage propagation it will be possible to combine damage tolerant structural design, monitoring systems, inspection techniques a...

This paper documents results to date from the Rotorcraft Acoustic Characterization and Mitigation activity under the NASA Subsonic Rotary Wing Project. The primary goal of this activity is to develop a NASA rotorcraft impulsive noise prediction capability which uses first principles fluid dynamics and structural dynamics. During this effort, elastic blade motion and co-processing capabilities h...

We address the problem of H 1 gain-scheduling of a magnetic bearing/rotor system with the speed of the rotor being the scheduling parameter. The rotor exhibits signiicant gyroscopics. As a result, the plant dynamics change with the rotor speed. Recent results in the theory of LPV systems can be used to design robust, gain-scheduled controllers for such a system. As opposed to traditional gain-s...

The effects of variation of blade torsion frequency on rotor performance and structural loads are investigated for a 1/rev active flap rotor and baseline rotor (no active control). The UH-60A four-bladed articulated main rotor is studied at a high-speed forward flight condition. The torsion frequencies are varied by modifying the spanwise torsional stiffness of the blade and/or the pitch link s...

This paper presents the development of a multibody dynamics model of a VTOL teetering rotor. The developed model includes a teetering hub, containing a flexure and torque tube, rotor blades, pitch links, and swashplate system. A non-teetering rotor configuration, which modified the baseline teetering rotor by removing the teetering hinge, is also developed, and its aeromechanics characteristics...

We address the problem of H gain scheduling of a magnetic bearing rotor system with the speed of the rotor being the scheduling parameter The rotor exhibits signi cant gyroscopics As a result the plant dynamics change with the rotor speed Recent results in the theory of LPV systems can be used to design robust gain scheduled controllers for such a system As opposed to traditional gain schedulin...