Nonlinear Dynamic Behavior of a Motorcycle’s Forecarriage During Braking

An experimental and numerical experience was carried out to investigate the nonlinear dynamic response of the forecarriage of a motorcycle, paying attention to a particular type of vibration that occurs during the braking. In fact, it was found that, in particular conditions of load on the handlebar, braking pressure, speed and temperature, the first flexural mode of the front fork is strongly excited. Thanks to the numerical model, solutions to these undesired vibrations were identified. Experimental tests were carried out modifying the design parameters of the motorcycles and of the braking system as suggested by the numerical model thus verifying that the purposed solutions were effective.

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Nonlinear Dynamic Behavior of Fixed Jacket-Type Offshore Platforms Subjected to Simultaneously Acting Wave and Earthquake Loads

23rd International Conference on Offshore Mechanics and Arctic Engineering, Volume 1, Parts A and B ◽

10.1115/omae2004-51498 ◽

2004 ◽

Cited By ~ 3

Author(s):

A. K. Etemad ◽

A. R. M. Gharabaghi ◽

M. R. Chenaghlou

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Dynamic Response ◽

Dynamic Behavior ◽

Persian Gulf ◽

Nonlinear Dynamic ◽

Longitudinal Component ◽

Offshore Platforms ◽

Nonlinear Dynamic Response ◽

Earthquake Loads

The nonlinear dynamic response of jacket-type offshore platform (which has been installed in Persian Gulf) under simultaneously wave and earthquake loads is conducted. The interaction between soil and piles is modeled by Konagai-Nogami model. The structure is modeled by finite element method. The analyses include models with the longitudinal component of earthquake and wave in the same direction and in different directions. The results indicate that when the longitudinal component of earthquake and wave are in the same direction, wave may reduce the response of studied platform and when they are in different directions, in some cases there is an increase in the response of platform.

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Influence of Lubricant Traction Coefficient on Cage's Nonlinear Dynamic Behavior in High-Speed Cylindrical Roller Bearing

Journal of Tribology ◽

10.1115/1.4036274 ◽

2017 ◽

Vol 139 (6) ◽

Cited By ~ 8

Author(s):

Wenhu Zhang ◽

Sier Deng ◽

Guoding Chen ◽

Yongcun Cui

Keyword(s):

Dynamic Response ◽

Dynamic Behavior ◽

Nonlinear Dynamic ◽

High Speed ◽

Roller Bearing ◽

Mass Center ◽

Nonlinear Dynamic Response ◽

Traction Coefficient ◽

Cylindrical Roller Bearing ◽

Cylindrical Roller

In this paper, the formulas of elastohydrodynamic traction coefficients of four Chinese aviation lubricating oils, namely, 4109, 4106, 4050, and 4010, were obtained by a great number of elastohydrodynamic traction tests. The nonlinear dynamics differential equations of high-speed cylindrical roller bearing were built on the basis of dynamic theory of rolling bearings and solved by Hilber–Hughes–Taylor (HHT) integer algorithm with variable step. The influence of lubricant traction coefficient on cage's nonlinear dynamic behavior was investigated, and Poincaré map was used to analyze the influence of four types of aviation lubricating oils on the nonlinear dynamic response of cage's mass center. The period of nonlinear dynamic response of cage's mass center was used to assess cage's stability. The results of this paper provide the theoretical basis for selection of aviation lubricating oil.

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Nonlinear Dynamic Response of Elastic Slider-Crank Mechanism

Journal of Engineering for Industry ◽

10.1115/1.3427883 ◽

1971 ◽

Vol 93 (1) ◽

pp. 251-262 ◽

Cited By ~ 52

Author(s):

B. V. Viscomi ◽

R. S. Ayre

Keyword(s):

Dynamic Response ◽

Dynamic Behavior ◽

Nonlinear Dynamic ◽

Connecting Rod ◽

Nonlinear Dynamic Response ◽

Dimensionless Parameters ◽

Crank Angle ◽

Crank Mechanism ◽

Bending Response

An investigation of the vibratory bending response of the elastic connecting rod of a slider-crank mechanism is presented. The response of the system is found to be dependent upon five dimensionless parameters. These are classified as the length, mass, damping, external piston force, and frequency parameters; and the effects of these parameters on the response of the system are investigated. The dynamic behavior is described as graphs of nondimensionalized deflection versus crank angle. Solutions of the linear as well as the nonlinear forms of the equations are included.

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Nonlinear dynamic response and bifurcation of asymmetric rotor system supported in axial-grooved gas-lubricated bearings

Journal of Low Frequency Noise Vibration and Active Control ◽

10.1177/14613484211052714 ◽

2021 ◽

pp. 146134842110527

Author(s):

Sha Li ◽

Yanjun Lu ◽

Yongfang Zhang ◽

Hongbo Luo ◽

Song Wang ◽

...

Keyword(s):

Numerical Model ◽

Dynamic Response ◽

Rational Function ◽

Nonlinear Dynamic ◽

Rotor System ◽

Dynamic Responses ◽

Function Model ◽

Nonlinear Dynamic Response ◽

Asymmetric Rotor ◽

The Rational Function Model

Dynamic characteristics of the asymmetric rotor system supported in axial-grooved gas-lubricated bearings are studied. In order to solve nonlinear dynamic response of rotor system effectively, a hybrid numerical model is established by coupling the motion equation of rotor with the rational function model of the gas film forces. The rational function model of the gas film forces of gas-lubricated bearing is established based on vector fitting theory. By using the hybrid numerical model, the repeated calculations of the unsteady Reynolds equation and gas film forces are avoided; the continuous rotor trajectory and the dynamic gas film forces can be calculated simultaneously; and for the rotor system supported in the same bearings, the computing cost can be saved effectively. The nonlinear dynamic responses of asymmetric rotor system supported in axial-grooved gas-lubricated bearings are investigated by trajectory diagrams, frequency spectrum, Poincaré maps, and time series. The bifurcations are analyzed by the bifurcation diagrams with different rotating speeds and mass eccentricities. The dynamic behaviors of the asymmetric rotor system appear complex nonlinear dynamic phenomenon and specific bifurcation characteristics.

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Complexity evaluation of nonlinear dynamic behavior of mechanisms with clearance joints by using the fractal method

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406214531251 ◽

2014 ◽

Vol 228 (18) ◽

pp. 3482-3495 ◽

Cited By ~ 7

Author(s):

Wuweikai Xiang ◽

Shaoze Yan ◽

Jianing Wu ◽

Robert X Gao

Keyword(s):

Dynamic Response ◽

Dynamic Behavior ◽

Nonlinear Dynamic ◽

Correlation Dimension ◽

Nonlinear Dynamic Response ◽

Fractal Method ◽

Motion Equations ◽

Clearance Joints ◽

Nonlinear Dynamic Characteristics ◽

Crank Mechanism

Dynamic behavior of mechanisms with clearance joints often exhibits nonlinear dynamic characteristics due to the collisions between the journal and bearing. However, previous studies could not quantify the complexity of the dynamic response. In this paper, based on the Poincaré map and correlation dimension, a fractal method is proposed to evaluate the complexity of nonlinear dynamic response of mechanisms with clearance joints. Motion equations of mechanical systems with clearance joints are described. A slider–crank mechanism is employed to demonstrate the efficiency of the fractal method and to discuss the influence of the clearance size and crank speed on the complexity of the dynamic response.

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