In this paper, a general linear time-varying multiple-axis (LTVMA) vibration model of shield tunnel boring machine (TBM) cutterhead driving system is established. The corresponding multiple inputs and multiple outputs (MIMO) state-space model is also presented. The linear vibration model is analysed, and the vibration-torque transfer function matrix and the vibration-torque static gain matrix a...

Significant levels of undesired vibration and noise are inherent in transport and combat vehicles, particularly in helicopters and propeller aircraft. Therefore, it is important to investigate techniques that reduce vibration and noise in the cabin to improve habitability, effectiveness, and safety for passengers. In addition, continuous exposure may lead to long-term physiological effects. In ...

The aim of this work is the application of the phase variation in vibration signal for fault detection on rotating machines. The vibration signal from the machine is modulated in amplitude and phase around a carrier frequency. The modulating signal in phase is determined after the Hilbert transform and is used, with the Fast Fourier Transform, to extract the harmonics spectrum in phase. This me...

This paper presents an integration design scheme and an optimization control strategy for electric wheels to suppress the in-wheel vibration and improve vehicle ride comfort. The in-wheel motor is considered as a dynamic vibration absorber (DVA), which is isolated from the unsprung mass by using a spring and a damper. The proposed DVA system is applicable for both the inner-rotor motor and oute...

in this paper, exact solution for two-plane transverse vibration analysis of axial-loaded multi-step timoshenko rotor carrying concentrated masses is presented. each attached element is considered to have both translational and rotational inertia. forward and backward frequencies and corresponding modes are obtained using transfer matrix method (tmm). the effect of the angular velocity of spin,...

A two-parameter deformation of the Lie algebra u2 is used, in conjunction with the rotor system and the oscillator system, to generate a model for rotation-vibration spectroscopy of molecules and nuclei.

Title of Dissertation: Individual Blade Control for Vibration Reduction of a Helicopter with Dissimilar Blades Beatrice Roget, Doctor of Philosophy, 2004 Dissertation directed by: Professor Inderjit Chopra Department of Aerospace Engineering A control method is proposed to reduce vibrations in helicopters using active trailing-edge flaps on the rotor blades. The novelty of the method is that ea...

This study develops a novel balancing method named as Low-Speed Holo-Balancing (LSHB), which can balance the flexible rotor without test run at high speeds. The principle of LSHB is mainly based on the holospectrum technique with following specialties. Firstly, the vibration response of rotor is described by three-dimensional holospectrum using multi-sensor fusion, instead of information from a...