Impact analysis of magnification level of multisensor measuring machine optics at the accuracy of measurement geometrical features

This study was designed to test the accuracy of measurement methods for assessment of force and tooth movement in orthodontic procedures. Daily in vivo measurements of the force produced by activated archwires showed that the initial force declined substantially (by 20 per cent of mean value) within 3 days. Both the ‘trueness’ (validity) and precision of the force measurements, obtained with a strain gauge, were found to be high (SD values were 1·0 cN and 0·4 cN, respectively). Horizontal tooth movements were measured with three different instruments: a slide calliper, a co-ordinate measuring machine, and laser measuring equipment based on holograms. There was a good level of agreement between these methods. This was also confirmed by calibration data. The precision of the methods was (SD values) 0·06, 0·07, and 0·13 mm, respectively. The benefits of the use of the co-ordinate measuring machine are obvious, since it can measure tooth movements in relation to reference planes in all directions.

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Study on the Method of Error Identification and Compensation for Gear Measuring Center

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.482-484.1821 ◽

2012 ◽

Vol 482-484 ◽

pp. 1821-1828

Author(s):

Peng Wan ◽

Jun Jie Guo ◽

Hai Tao Li

Keyword(s):

High Precision ◽

Error Detection ◽

Geometric Error ◽

Precision Measurements ◽

Tooth Surface ◽

Geometric Errors ◽

Detection Technology ◽

Accuracy Of Measurement ◽

Measuring Machine ◽

Multi Body

Gear Measuring Center(GMC) is commonly used to test error of the tooth surface of the gear, whose geometric accuracy directly impacts on the accuracy of measurement. How to quickly and accurately detect space geometric error of the measuring machine and compensate becomes the essential means of high-precision measurements. According to the problem above, in the paper, three-beams laser detection technology is proposed. The detection of the geometric errors of the linear axis was achieved. The accurate measurement for the position and attitude of the plane mirror on measurement seat was achieved based on laser telemetry principle. The positioning error, the pitching angle errors, the deflection angle errors and the straightness errors were separated. And then based on multi-body system theory, by using of homogeneous coordinate transformation, the error compensation model of 4-axis measuring machine which includes three shifting pairs and one revolute pair was established, and the algorithm was given in the paper. The theoretical foundation for real-time compensation of 4-axis GMC was established. The geometric errors of GMC can be improved by the method of the error detection and compensation. The method plays a very important role in high-precision measurements.

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Impact Analysis of Variation in Geometrical Features on Intrinsic Characteristics of Capacitive Micro-machined Ultrasonic Transducers

International Journal of Engineering ◽

10.5829/ije.2018.31.11b.07 ◽

2018 ◽

Vol 31 (11) ◽

Keyword(s):

Impact Analysis ◽

Ultrasonic Transducers ◽

Geometrical Features ◽

Analysis Of Variation

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A study of the accuracy of measurement on a coordinate measuring machine using reference ring

YOUNG RUSSIA: HIGH TECHNOLOGY – INTO INDUSTRY ◽

10.25206/2310-4597-2019-1-20-23 ◽

2019 ◽

pp. 020-023

Author(s):

A. V. Tignibidin ◽

◽

S. H. Huzhamuratov ◽

Keyword(s):

Coordinate Measuring Machine ◽

Accuracy Of Measurement ◽

Measuring Machine

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The testing of plane surfaces

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1912.0015 ◽

1912 ◽

Vol 86 (586) ◽

pp. 227-234

Keyword(s):

Degree Of Freedom ◽

Small Areas ◽

Know How ◽

Standard Measuring ◽

Contact Points ◽

Trade Practice ◽

Standard Plate ◽

Accuracy Of Measurement ◽

Measuring Machine

There is only one way of originating a true plane, viz., to make it in triplicate and to work all three surfaces so as to obtain a "fit" between them. In engineering trade practice this is done when a standard plate is required, and any one of the three plates thus obtained can be used as being truly plane (within the limits of the "raddle" process) for the making of further surface-plates. In many modern exact apparatus, e. g. , a standard measuring machine or a Michelson's interferometer, accuracy of measurement directly depends on the truth of the plane "ways" of the bed along which the various parts of the apparatus slide. These ways are made either by scraping or lapping, and it is of importance to know what errors occur from place to place along the bed due to defective workmanship. The bed generally has three worked planes all inclined to one another, and the movable parts rest on these by, five contact points, thus allowing only one degree of freedom. These five feet bear on the surfaces below by small areas, and amongst other considerations it is important to know how far these feet rise and fall in and out of the scraping marks if the surfaces have been made by scraping.

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IMPROVING THE ACCURACY OF VIBRATION MEASUREMENT RESULTS

Informatyka Automatyka Pomiary w Gospodarce i Ochronie Środowiska ◽

10.35784/iapgos.2713 ◽

2021 ◽

Vol 11 (3) ◽

pp. 14-17

Author(s):

Anzhelika Stakhova ◽

Volodymyr Kvasnikov

Keyword(s):

Measuring Transducer ◽

Vibration Measurement ◽

Vibration Measurements ◽

Additional Information ◽

Current State ◽

Urgent Task ◽

Measurement Results ◽

Accuracy Of Measurement ◽

Measuring Machine ◽

Vibration Measuring

The current state of control of vibration measuring equipment is studied in the work, the analysis of technologies of control of vibrating measuring machine equipment is carried out. It is determined that during the control a sufficient requirement for the analysis of changes in the state over time is to conduct periodic vibration measurements in the same modes of operation of the object. Therefore, the urgent task is to increase the reliability and accuracy of measurement results. It can be enhanced by obtaining additional information. For this purpose, recommendations for optimizing the vibration control points of the mechanism are formed. To increase the accuracy of measurement results when controlling the equipment for vibration signals, the methods of mounting the measuring transducer in the equipment monitoring system are considered. It is shown that the method of mounting the measuring transducer can affect the results of vibration measurements.

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Measurements of the Cape Astrometric Survey of the Southern Hemisphere

International Astronomical Union Colloquium ◽

10.1017/s0252921100074534 ◽

1978 ◽

Vol 48 ◽

pp. 515-521

Author(s):

W. Nicholson

Keyword(s):

Southern Hemisphere ◽

Automatic Measuring ◽

Measuring Machine ◽

Final Selection ◽

Selection Of

SummaryA routine has been developed for the processing of the 5820 plates of the survey. The plates are measured on the automatic measuring machine, GALAXY, and the measures are subsequently processed by computer, to edit and then refer them to the SAO catalogue. A start has been made on measuring the plates, but the final selection of stars to be made is still a matter for discussion.

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Etching of Polymers by Oxygen Plasma

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101797 ◽

1968 ◽

Vol 26 ◽

pp. 408-409

Author(s):

Virgil Peck ◽

W. L. Carter

Keyword(s):

Molecular Weight ◽

Oxygen Plasma ◽

Flow Time ◽

Microscopical Study ◽

Surface Layers ◽

Organic Vapors ◽

Sample Position ◽

Accuracy Of Measurement ◽

Bulk Polymers ◽

Electron Microscopical

Any electron microscopical study of the morphology of bulk polymers has throughout the years been hampered by the lack of any real ability to produce meaningful surface variations for replication. True etching of polymers should show crystalline and amorphous regions in some form of relief. The use of solvents, acids, organic vapors, and inert ion bombardment to etch samples has proved to be useful only in limited applications. Certainly many interpretations of these results are subject to question.The recent use of a radiofrequency (R. F.) plasma of oxygen to degrade and remove organic material with only minor heating has opened a new possibility for etching polymers. However, rigid control of oxygen flow, time, current, and sample position are necessary in order to obtain reproducible results. The action is confined to surface layers; the molecular weight of the polymer residue after heavy etching is the same as the molecular weight of the polymer before attack, within the accuracy of measurement.

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