MOTION OF A HYDRAULIC PARALLEL LINK SERVOMECHANISM WITH THREE DEGREES OF FREEDOM

Abstract Background The trend in miniaturisation of structural components and continuous development of more advanced crystal plasticity models point towards the need for understanding cyclic properties of engineering materials at the microscale. Though the technology of focused ion beam milling enables the preparation of micron-sized samples for mechanical testing using nanoindenters, much of the focus has been on monotonic testing since the limited 1D motion of nanoindenters imposes restrictions on both sample preparation and cyclic testing. Objective/Methods In this work, we present an approach for cyclic microcantilever bending using a micromanipulator setup having three degrees of freedom, thereby offering more flexibility. Results The method has been demonstrated and validated by cyclic bending of Alloy 718plus microcantilevers prepared on a bulk specimen. The experiments reveal that this method is reliable and produces results that are comparable to a nanoindenter setup. Conclusions Due to the flexibility of the method, it offers straightforward testing of cantilevers manufactured at arbitrary position on bulk samples with fully reversed plastic deformation. Specific microstructural features, e.g., selected orientations, grain boundaries, phase boundaries etc., can therefore be easily targeted.

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Average Modelling of a Dual Half Bridge Converter Modulated with Three Degrees of Freedom

IEEE Transactions on Transportation Electrification ◽

10.1109/tte.2021.3062443 ◽

2021 ◽

pp. 1-1

Author(s):

Fei Gao ◽

Ngoni Mugwisi ◽

Daniel J. Rogers

Keyword(s):

Degrees Of Freedom ◽

Three Degrees Of Freedom

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Galloping Stability and Wind Tunnel Test of Iced Quad Bundled Conductors considering Wake Effect

Discrete Dynamics in Nature and Society ◽

10.1155/2020/8885648 ◽

2020 ◽

Vol 2020 ◽

pp. 1-15

Author(s):

Xiaohui Liu ◽

Ming Zou ◽

Chuan Wu ◽

Mengqi Cai ◽

Guangyun Min ◽

...

Keyword(s):

Wind Tunnel ◽

Transmission Lines ◽

Degrees Of Freedom ◽

Wind Tunnel Test ◽

Aerodynamic Coefficients ◽

Wake Effect ◽

Aerodynamic Coefficient ◽

Set Up ◽

The Stability ◽

Three Degrees Of Freedom

A new quad bundle conductor galloping model considering wake effect is proposed to solve the problem of different aerodynamic coefficients of each subconductor of iced quad bundle conductor. Based on the quasistatic theory, a new 3-DOF (three degrees of freedom) galloping model of iced quad bundle conductors is established, which can accurately reflect the energy transfer and galloping of quad bundle conductor in three directions. After a series of formula derivations, the conductor stability judgment formula is obtained. In the wind tunnel test, according to the actual engineering situation, different variables are set up to accurately simulate the galloping of iced quad bundle conductor under the wind, and the aerodynamic coefficient is obtained. Finally, according to the stability judgment formula of this paper, calculate the critical wind speed of conductor galloping through programming. The dates of wind tunnel test and calculation in this paper can be used in the antigalloping design of transmission lines.

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