Angular Motion Decoupling and Attitude Determination Based on High Dynamic Gyro

Rocket attitude determination by a Fourier method

Canadian Journal of Physics ◽

10.1139/p79-103 ◽

1979 ◽

Vol 57 (5) ◽

pp. 728-732 ◽

Cited By ~ 1

Author(s):

D. W. Green ◽

B. G. Wilson

Keyword(s):

Optical Sensor ◽

Additional Data ◽

Attitude Determination ◽

Fourier Method ◽

Angular Motion ◽

Sounding Rocket ◽

Free Flight ◽

Transverse Axis ◽

Magnetometer Data

It is shown that the parameters completely specifying the angular motion of a symmetrical sounding rocket in torque-free flight may in general be determined from a Fourier-transformed segment of transverse-axis magnetometer data, with limited additional data from an auxiliary optical sensor. The method is simple and rapid, and an example is worked out.

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A Study on Information Fusion of AHRS Based on DSP

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.271-273.802 ◽

2011 ◽

Vol 271-273 ◽

pp. 802-807

Author(s):

Hong Sheng Tan ◽

Xia Ming Yuan ◽

Ji Hong Zhu

Keyword(s):

Attitude Determination ◽

Low Cost ◽

Dynamic Performance ◽

Attitude Measurement ◽

Determination System ◽

Navigation Error ◽

High Dynamic ◽

Calculation System ◽

Gyro Drift ◽

Effective Integration

For the angular velocity gyro drift and noise and the inertial navigation solution of the integral nature, the navigation error of the attitude will accumulate over time. With the increase of navigation time, the system may fail. In high dynamic motion the accelerometer / magnetometer attitude measurement navigation system will not work properly. Therefore, the accelerometer / magnetometer attitude determination system, haven’t no drift, but poor dynamic performance. This article will realize a low-cost, precision Attitude Calculation System with more effective integration of the two.

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Reference Coordinate System Requirements for Geophysics

International Astronomical Union Colloquium ◽

10.1017/s0252921100050946 ◽

1975 ◽

Vol 26 ◽

pp. 87-92

Author(s):

P. L. Bender

Keyword(s):

Coordinate System ◽

Polar Motion ◽

Main Part ◽

Measurement Techniques ◽

Reference Points ◽

Angular Motion ◽

Coordinate Systems ◽

Axis Of Rotation ◽

The Earth ◽

Fixed System

AbstractFive important geodynamical quantities which are closely linked are: 1) motions of points on the Earth’s surface; 2)polar motion; 3) changes in UT1-UTC; 4) nutation; and 5) motion of the geocenter. For each of these we expect to achieve measurements in the near future which have an accuracy of 1 to 3 cm or 0.3 to 1 milliarcsec.From a metrological point of view, one can say simply: “Measure each quantity against whichever coordinate system you can make the most accurate measurements with respect to”. I believe that this statement should serve as a guiding principle for the recommendations of the colloquium. However, it also is important that the coordinate systems help to provide a clear separation between the different phenomena of interest, and correspond closely to the conceptual definitions in terms of which geophysicists think about the phenomena.In any discussion of angular motion in space, both a “body-fixed” system and a “space-fixed” system are used. Some relevant types of coordinate systems, reference directions, or reference points which have been considered are: 1) celestial systems based on optical star catalogs, distant galaxies, radio source catalogs, or the Moon and inner planets; 2) the Earth’s axis of rotation, which defines a line through the Earth as well as a celestial reference direction; 3) the geocenter; and 4) “quasi-Earth-fixed” coordinate systems.When a geophysicists discusses UT1 and polar motion, he usually is thinking of the angular motion of the main part of the mantle with respect to an inertial frame and to the direction of the spin axis. Since the velocities of relative motion in most of the mantle are expectd to be extremely small, even if “substantial” deep convection is occurring, the conceptual “quasi-Earth-fixed” reference frame seems well defined. Methods for realizing a close approximation to this frame fortunately exist. Hopefully, this colloquium will recommend procedures for establishing and maintaining such a system for use in geodynamics. Motion of points on the Earth’s surface and of the geocenter can be measured against such a system with the full accuracy of the new techniques.The situation with respect to celestial reference frames is different. The various measurement techniques give changes in the orientation of the Earth, relative to different systems, so that we would like to know the relative motions of the systems in order to compare the results. However, there does not appear to be a need for defining any new system. Subjective figures of merit for the various system dependon both the accuracy with which measurements can be made against them and the degree to which they can be related to inertial systems.The main coordinate system requirement related to the 5 geodynamic quantities discussed in this talk is thus for the establishment and maintenance of a “quasi-Earth-fixed” coordinate system which closely approximates the motion of the main part of the mantle. Changes in the orientation of this system with respect to the various celestial systems can be determined by both the new and the conventional techniques, provided that some knowledge of changes in the local vertical is available. Changes in the axis of rotation and in the geocenter with respect to this system also can be obtained, as well as measurements of nutation.

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