VLA proper motion constraints on the origin, age, and potential magnetar future of PSR J1734-3333

AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic flux in the photosphere. The velocity scatter of individual measured points is about one order higher than the accuracy of measurements.

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Status of “AGK4” Project

International Astronomical Union Colloquium ◽

10.1017/s0252921100074558 ◽

1978 ◽

Vol 48 ◽

pp. 527-533

Author(s):

Chr. de Vegt

Keyword(s):

Northern Hemisphere ◽

Proper Motion ◽

The Mean ◽

Spectral Bandpass

The present accuracy limit for the majority of fainter stars on the northern hemisphere is set by the AGK2/3-catalogue, recently completely finished, but it should be noted that its epoch is much earlier (1960). Furtheron the AGK3-catalogue is a direct repetition of the AGK2, the plates have been taken with the same astrograph in a broad blue spectral bandpass and measured visually with the same equipment, therefore virtually an instrumental standard of 1930 is realized again. Figure 1 shows the mean errors of the AGK2/3 catalogue positions as a function of magnitude. The best accuracy for the AGK2/3 data is obtained for the stars of about ninth magnitude: 017 (AGK2) and 020 (AGK3) but decreases for the faint stars with mpg11 to 019 (AGK2) and Pg 027 (AGK3). Here the AGK3 data are even less accurate. With increasing distance to the catalogue epochs, the accuracy of positions decreases due to the proper motion errors. In the upper part of figure 2 the dependence of the AGK2/3 catalogue accuracy on time is shown for the faint stars separately and an averaged value.

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Status of the Lick Proper Motion Program

International Astronomical Union Colloquium ◽

10.1017/s0252921100074339 ◽

1978 ◽

Vol 48 ◽

pp. 387-388

Author(s):

A. R. Klemola

Keyword(s):

Proper Motion ◽

The Future

Second-epoch photographs have now been obtained for nearly 850 of the 1246 fields of the proper motion program with centers at declination -20° and northwards. For the sky at 0° and northward only 130 fields remain to be taken in the next year or two. The 270 southern fields with centers at -5° to -20° remain for the future.

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Vanishing Point/vehicle Motion Constraints Aided Ground Vehicle Navigation

Proceedings of the 2017 International Technical Meeting of The Institute of Navigation ◽

10.33012/2017.14892 ◽

2017 ◽

Author(s):

Zhenbo Liu ◽

Naser El-Sheimy ◽

Chunyang Yu ◽

Yongyuan Qin

Keyword(s):

Vehicle Navigation ◽

Vanishing Point ◽

Ground Vehicle ◽

Motion Constraints ◽

Vehicle Motion

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UWB/IMU Integration with Adaptive Motion Constraints to Support UXO Mapping

Proceedings of the ION 2017 Pacific PNT Meeting ◽

10.33012/2017.15070 ◽

2017 ◽

Cited By ~ 1

Author(s):

Zoltan Koppanyi ◽

Vaclav Navratil ◽

Haowei Xu ◽

Charles K. Toth ◽

Dorota Grejner-Brzezinska

Keyword(s):

Motion Constraints ◽

Adaptive Motion

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A hierarchical constraint approach for dynamic modeling and trajectory tracking control of a mobile robot

Journal of Vibration and Control ◽

10.1177/1077546321999185 ◽

2021 ◽

pp. 107754632199918

Author(s):

Rongrong Yu ◽

Shuhui Ding ◽

Heqiang Tian ◽

Ye-Hwa Chen

Keyword(s):

Mobile Robot ◽

Dynamic Modeling ◽

Trajectory Tracking ◽

Tracking Control ◽

Wheeled Mobile Robot ◽

Structural Constraints ◽

Control Force ◽

Trajectory Tracking Control ◽

Motion Constraints ◽

Constraint Approach

The dynamic modeling and trajectory tracking control of a mobile robot is handled by a hierarchical constraint approach in this study. When the wheeled mobile robot with complex generalized coordinates has structural constraints and motion constraints, the number of constraints is large and the properties of them are different. Therefore, it is difficult to get the dynamic model and trajectory tracking control force of the wheeled mobile robot at the same time. To solve the aforementioned problem, a creative hierarchical constraint approach based on the Udwadia–Kalaba theory is proposed. In this approach, constraints are classified into two levels, structural constraints are the first level and motion constraints are the second level. In the second level constraint, arbitrary initial conditions may cause the trajectory to diverge. Thus, we propose the asymptotic convergence criterion to deal with it. Then, the analytical dynamic equation and trajectory tracking control force of the wheeled mobile robot can be obtained simultaneously. To verify the effectiveness and accuracy of this methodology, a numerical simulation of a three-wheeled mobile robot is carried out.

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Linking the FK5 to the ICRF

Highlights of Astronomy ◽

10.1017/s1539299600020840 ◽

1998 ◽

Vol 11 (1) ◽

pp. 313-316

Author(s):

F. Mignard ◽

M. Froeschile

Keyword(s):

Reference Frame ◽

Proper Motion ◽

Harmonic Functions ◽

Optical Reference ◽

Precessional Motion ◽

Precession Constant

Abstract The Hipparcos optical reference frame is compared to the basic FK5 in order to determine the orientation at T0 = 1991.25 and the global spin between the two frames. The components of the spin are significant and suggest a correction the IAU76 value of the precession constant and to a possible non-precessional motion of the equinox of the FK5. The regional errors are analysed with harmonic functions and found to be as large as 150 mas in position and 3 mas/yr in proper motion.

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Hipparcos Astrometric Results

Highlights of Astronomy ◽

10.1017/s1539299600021973 ◽

1998 ◽

Vol 11 (1) ◽

pp. 536-538

Author(s):

J. Kovalevsky

Keyword(s):

Proper Motion ◽

Reference System ◽

Systematic Errors ◽

One Dimensional

Abstract The astrometric results of Hipparcos include the positions at epoch (1991.25), the proper motion in the new IAU extragalactic reference system (ICRS), and parallaxes for about 118 000 stars. One dimensional positions are also given for 48 asteroids and 3 satellites. Due to the non-isotropy of the scanning law, the uncertainties are position dependent. Some indications of the remaining correlations are given. Various tests and comparisons show that systematic errors in parallax, if any, are not larger than 0.1 millisecond of arc.

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VLBI Pulsar Astrometry

Symposium - International Astronomical Union ◽

10.1017/s007418090022161x ◽

2001 ◽

Vol 205 ◽

pp. 404-407

Author(s):

R.M. Campbell

Keyword(s):

Proper Motion ◽

Vlbi Observations ◽

Recent Developments

I briefly review the means by which VLBI observations can determine the position, proper motion, and parallax of a pulsar, consider a subset of the applications of such results, and highlight recent developments in pulsar gating at JIVE.

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