Research on Locking Position Determination of Space-arm Based on Modal Analysis

A novel modal analysis technique called impact-synchronous modal analysis (ISMA) was introduced in previous research. With the utilization of impact-synchronous time averaging (ISTA), this modal analysis can be performed in presence of ambient forces whereas the conventional analysis method requires machines to be totally shut down. However, lack of information of phase angles with respect to impact in ISMA has caused it to be labor-intensive and time-consuming. An automated impact device (AID) is introduced in this study in the effort to replace the manually operated impact hammer and prepare it to be used in the current practice of ISMA on the purpose of enhancing its effectiveness and practicability. Impact profile and isolation effect are noted to be the contributing parameters in this study. This paper devoted on calibrating and controlling of the AID which gives the desired impact profiles as compared to the manual impact hammer. The AID is found effective in the determination of dynamic characteristics when the device is isolated from the boundary condition of the test structure.

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Three-point-support method based on position determination of supports and wafers to eliminate gravity-induced deflection of wafers

Precision Engineering ◽

10.1016/j.precisioneng.2016.06.003 ◽

2016 ◽

Vol 46 ◽

pp. 339-348 ◽

Cited By ~ 6

Author(s):

Haijun Liu ◽

Xianglong Zhu ◽

Renke Kang ◽

Zhigang Dong ◽

Xiuyi Chen

Keyword(s):

Position Determination ◽

Point Support

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Solutions to the Vector Tetrahedron Equation

Journal of Engineering for Industry ◽

10.1115/1.3670802 ◽

1965 ◽

Vol 87 (2) ◽

pp. 228-234 ◽

Cited By ~ 11

Author(s):

Milton A. Chace

Keyword(s):

Closed Form ◽

Digital Computer ◽

Three Dimensional ◽

Dimensional Vector ◽

Spherical Coordinates ◽

Tetrahedron Equation ◽

Position Determination ◽

Closed Form Solutions

A set of nine closed-form solutions are presented to the single, three-dimensional vector tetrahedron equation, sum of vectors equals zero. The set represents all possible combinations of unknown spherical coordinates among the vectors, assuming the coordinates are functionally independent. Optimum use is made of symmetry. The solutions are interpretable and can be evaluated reliably by digital computer in milliseconds. They have been successfully applied to position determination of many three-dimensional mechanisms.

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Direct position determination of narrowband radio transmitters

2004 IEEE International Conference on Acoustics, Speech, and Signal Processing ◽

10.1109/icassp.2004.1326241 ◽

2004 ◽

Cited By ~ 3

Author(s):

A.J. Weiss

Keyword(s):

Position Determination ◽

Radio Transmitters

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Automated Determination of the Position of Ships by Satellites

Journal of Navigation ◽

10.1017/s0373463300024528 ◽

1967 ◽

Vol 20 (03) ◽

pp. 281-285

Author(s):

H. C. Freiesleben

Keyword(s):

Celestial Body ◽

World Wide ◽

Artificial Satellites ◽

Radio Waves ◽

The Moon ◽

Position Determination ◽

The Earth ◽

Navigational Aids ◽

Automated Determination

It has recently been suggested that 24-hour satellites might be used as navigational aids. To what category of position determination aids should these be assigned ? Is a satellite of this kind as it were a landmark, because, at least in theory, it remains fixed over the same point on the Earth's surface, in which case it should be classified under land-based navigation aids ? Is it a celestial body, although only one tenth as far from the Earth as the Moon ? If so, it is an astronomical navigation aid. Or is it a radio aid ? After all, its use for position determination depends on radio waves. In this paper I shall favour this last view. For automation is most feasible when an object of observation can be manipulated. This is easiest with radio aids, but it is, of course, impossible with natural stars.At present artificial satellites have the advantage over all other radio aids of world-wide coverage.

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