In order to measure the whole range of components of a gravity gradient with a miniaturized system, a simultaneous sensing mechanism of both the inline and cross components is presented. Based on the screw theory, the freedoms of the sensing mechanism of the superconductor gravity gradient are analyzed. The wrench of the free space and reciprocity of the screw theory are adopted to obtain the twists to express constraints. One symmetry type mechanism with redundancy constraints is deduced, which can be built by flexible elements according to a parallel mechanism form. Based on the transverse and vertical flexible hinges of flexible Hooke hinge, the function of equivalent spherical hinge can be realized. The deformation of the flexible elements is analyzed when the pivoted arm moves along the axial direction or rotates around the same axis. According to the geometrical relationship and the principle of conservation of energy, the axial rigidity and rotational stiffness are deduced. By means of finite element simulation, it can be concluded that the stiffness of the designed motion is influenced by the parameters of the mechanism. The simulation results verify the analysis process.
JIA Ming
,
YANG Gongliu
. Analysis of Sensing Mechanism for Gravity Gradient Based on Superconductivity[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2012
, (4)
: 672
-678
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DOI: CNKI:11-1929/V.20111221.1132.006
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