Experimento Mecânico para Medir a Velocidade da Gravidade

The authors have experience with the gravitational wave detector SCHENBERG, which is a resonant mass developed by the Brazilian GRAVITON. Its spherical antenna weighs 1150 kg and is monitored by six parametric ultralow noise transducers and is connected to the external environment by a suspension system designed to attenuate local, seismic and non-seismic noise, operating at a temperature of 4 K. the recognition has acquired the idea of doing an experiment to measure the speed of gravity. Using monocrystalline sapphire with very high mechanical and electrical Qs, microwave sources with ultra-low phase noise, suspensions designed by Finite Element Modeling, parametric microwave transducers, excellent noise filtering properties of resonant mass and the development of high-speed rotation machines guided the authors to design the experiment. The experiment will measure the oscillations caused by the gravitational interaction with an amplitude of the order of 0.1 am 10^-19m).

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An integrated thermo-mechanical-dynamic model to characterize motorized machine tool spindles during very high speed rotation

International Journal of Machine Tools and Manufacture ◽

10.1016/s0890-6955(03)00091-9 ◽

2003 ◽

Vol 43 (10) ◽

pp. 1035-1050 ◽

Cited By ~ 148

Author(s):

Chi-Wei Lin ◽

Jay F. Tu ◽

Joe Kamman

Keyword(s):

Machine Tool ◽

Dynamic Model ◽

High Speed ◽

High Speed Rotation ◽

Speed Rotation ◽

Very High

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Current Command Compensation Method for the PM Servo Motor Considering Voltage Saturation Caused by Both Rapid Change in the Current Command and High-Speed Rotation

IEEJ Transactions on Industry Applications ◽

10.1541/ieejias.134.691 ◽

2014 ◽

Vol 134 (7) ◽

pp. 691-698

Author(s):

Yoichi Egashira ◽

Masaya Harakawa ◽

Takayuki Ozaki ◽

Hiroto Takei ◽

Atsuo Haishi ◽

...

Keyword(s):

High Speed ◽

Rapid Change ◽

Compensation Method ◽

Servo Motor ◽

High Speed Rotation ◽

Speed Rotation ◽

Voltage Saturation

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Development of Fluid Pump using 1-DOF Control Self-Bearing Motor for High-Speed Rotation in Liquid Nitrogen

2020 23rd International Conference on Electrical Machines and Systems (ICEMS) ◽

10.23919/icems50442.2020.9290908 ◽

2020 ◽

Author(s):

Hirohisa Kato ◽

Mochimitsu Komori ◽

Ken-ichi Asami ◽

Nobuo Sakai

Keyword(s):

Liquid Nitrogen ◽

High Speed ◽

High Speed Rotation ◽

Speed Rotation

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Sound Noise Generated from Ball Bearing in High Speed Rotation

Bulletin of JSME ◽

10.1299/jsme1958.21.1306 ◽

1978 ◽

Vol 21 (158) ◽

pp. 1306-1310 ◽

Cited By ~ 7

Author(s):

Akio NAGAMATSU ◽

Masaho FUKUDA

Keyword(s):

High Speed ◽

Ball Bearing ◽

High Speed Rotation ◽

Speed Rotation

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Analysis of the Lubrication Regimes at the Small End and Big End of a Connecting Rod of a High Performance Motorbike Engine

ASME/STLE 2012 International Joint Tribology Conference ◽

10.1115/ijtc2012-61087 ◽

2012 ◽

Cited By ~ 1

Author(s):

Luca Bertocchi ◽

Matteo Giacopini ◽

Daniele Dini

Keyword(s):

Rotational Speed ◽

High Speed ◽

High Performance ◽

Hydrodynamic Lubrication ◽

Vertical Axis ◽

Connecting Rod ◽

Lubrication Regimes ◽

High Speed Rotation ◽

Speed Rotation ◽

Squeeze Effect

In the present paper, the algorithm proposed by Giacopini et. al. [1], based on a mass-conserving formulation of the Reynolds equation using the concept of complementarity is suitably extended to include the effects of compressibility, piezoviscosity and shear-thinning on the lubricant properties. This improved algorithm is employed to analyse the performance of the lubricated small end and big end bearings of a connecting rod of a high performance motorbike engine. The application of the algorithm proposed to both the small end and the big end of a con-rod is challenging because of the different causes that sustain the hydrodynamic lubrication in the two cases. In the con-rod big end, the fluid film is mainly generated by the relative high speed rotation between the rod and the crankshaft. The relative speed between the two races forms a wedge of fluid that assures appropriate lubrication and avoids undesired direct contacts. On the contrary, at the con-rod small end the relative rotational speed is low and a complete rotation between the mating surfaces does not occurs since the con-rod only oscillates around its vertical axis. Thus, at every revolution of the crankshaft, there are two different moments in which the relative rotational speed between the con-rod and the piston pin is null. Therefore, the dominant effect in the lubrication is the squeeze caused by the high loads transmitted through the piston pin. In particular both combustion forces and inertial forces contribute to the squeeze effect. This work shows how the formulation developed by the authors is capable of predicting the performance of journal bearings in the unsteady regime, where cavitation and reformation occur several times. Moreover, the effects of the pressure and the shear rate on the density and on the viscosity of the lubricant are taken into account.

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Research on Calibration Method of Tire Dynamic Balance Detection System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.542-543.828 ◽

2012 ◽

Vol 542-543 ◽

pp. 828-832 ◽

Cited By ~ 1

Author(s):

Jing Fang Yang ◽

Xian Ying Feng ◽

Hong Jun Fu ◽

Lian Fang Zhao

Keyword(s):

High Speed ◽

Detection System ◽

Dynamic Balance ◽

Calibration Method ◽

Engineering Practice ◽

Influence Coefficient ◽

Quality Factors ◽

High Speed Rotation ◽

Speed Rotation ◽

Upper Rim

Tire dynamic balance detection plays an important part in tire quality detection area. This paper uses the two-sided balance method to obtain the unbalance of the tire. According to the engineering practice, builds kinetic model and then introduces the calculating principle and operating procedures. In order to accurately determine the influence coefficient, a calibration method without tire is put forward. Further more, this new method is able to eliminate the unbalance caused by non-quality factors to some extent. But this method is presented based on the relative position invariance of the upper rim and lower rim, even both of them are under high-speed rotation situation. Finally, the experimental data acquired from both of the two methods are compared. The calibration method without tire is proved to be more feasible, efficient and accurate.

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