• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.1
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• pp.88-94
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• 2005

This paper presents the design and implementation of a receiver operating between a rotary machine encoder and DSP. The receiver connects with the encoder using 1 bit serial data and DSP using 16 bits bus line. The receiver and encoder use the different operating frequency each other. We suggest a new apparatus and method of synchronized code for header detection in 1bit serial communication. The system operating frequency can be changed into 20MHz or 60MHz by using the external port such as 'clk_select'.

• Journal of Electrical Engineering and Technology
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• v.13 no.2
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• pp.943-952
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• 2018

This paper presents a new type of absolute rotary encoder system based on the affine n-digit N-ary gray code. A brief comparison of the existing encoder systems is carried out in terms of resolution, encoding and decoding principles and number of sensor heads needed. Using the proposed method, two different types of encoder disks are designed, namely, color-coded disk and grayscale coded disk. The designed coded disk pattern is used to manufacture 3 digit 3 ary and 2 digit 5 ary grayscale coded disks respectively. The manufactured disk is used with the light emitter and photodetector assembly to design the entire encode system. Experimental analysis is done on the designed prototype with LabVIEW platform for data acquisition. A comparison of the designed system is done with the traditional binary gray code encoder system in terms of resolution, disk diameter, number of tracks and data acquisition system. The resolution of the manufactured system is 3 times higher than the conventional system. Also, for a 5 digit 5 ary coded encoder system, a resolution approximately 100 times better than the conventional binary system can be achieved. In general, the proposed encoder system gives $(N/2)^n$ times better resolution compared with the traditional gray coded disk. The miniaturization in diameter of the coded disk can be achieved compared to the conventional binary systems.

• The Journal of the Acoustical Society of Korea
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• v.33 no.1
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• pp.31-39
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• 2014

In this paper, two calibration methods for angular vibration pickups using a precision rotary encoder are proposed. The KRISS (Korea Research Institute of Standards and Science) primary angular vibration calibration system and the calibration procedures are briefly explained. The rotary encoder is shown to be calibrated in two methods: The one is to use the laser interferometer to calibrate the rotary encoder under test and the other is to exploit the certificate of the encoder supplied. Complex sensitivities measured from the first are shown to be less than 0.1 % difference in magnitude and $0.01^{\circ}$ difference in phase shift in reference to those of the primary calibration system. Their expanded uncertainties were observed to be less than 0.6 % in magnitude and $0.4^{\circ}$ in phase shift over the range of 0.4 to 200 Hz. Under the same calibration conditions, complex sensitivities evaluated by the second method are shown be 0.1 % difference in magnitude and $0.6^{\circ}$ difference in phase shift in reference to those of the primary calibration system. Their expanded uncertainties were seen to be less than 4.8 % in magnitude and $2.8^{\circ}$ in phase shift.

• Korean Journal of Crystallography
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• v.6 no.2
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• pp.88-92
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• 1995

Higly pure silicon crystals with an almost perfect lattice structure constityte a powerful metrological tool. The streographic standard prohection for the (111) orientation of diamond structure found by the Laue method shows angles between net planes of 60°. This value is known to be certain to some 10-8 rad. We have made a six-faced silicon polygon, and the (220) lattice planes of the polygon act as a reference angular standard. The information of angles between lattice planes could be taken by the X-ray diffraction. The angle of the rotary encoder have been calibrated using the silicon angle standard. The X-ray optics was double crystal arrangement.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.11
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• pp.160-166
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• 2002

In this paper, data acquisition and analysis of a measuring machine for marine engine's cams is discussed. A rotary encoder and linear scale of the machine to measure angular and linear displacement respectively are interfaced to the PC via encoder board with 2 channels. The design and measuring data are interpolated by cubic spline curves to compute the precision error which is defined by the maximum and minimum distances between two curves. The minimum zone fit of ISO is employed to evaluate the geometric deviation. The developed system takes only 5 minutes to measure and analyze while the CMM takes over 1 hours even with a skilled operator.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.9
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• pp.76-85
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• 2007

An optical rotary encoder is easy to implement for automatic control applications. In particular, the output of the encoder has a digital form pulse, which is also easy to be connected to a popular digital controller. By using the encoder, there are various angular velocity detecting methods, M-, T-, and M/T-method. Each of them has a property of its own. They have common limitation that the angular velocity detection period is strongly subject to the destination velocity magnitude in case of ultimate low range. They have ultimate long detection period or cannot even detect angular velocity at near zero velocity. This paper proposes a dual encoder system with two encoders of normal resolution. The dual encoder system is able to keep detection period moderately at near zero velocity and even detects zero velocity within nominal period. It is useful for detecting velocity in case of changing rotational direction at which there occurs zero velocity. In this paper, various experimental results are shown for the dual encoder system validity.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.6
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• pp.333-341
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• 2003

In induction motor control systems driven by the indirect vector control scheme, the rotor speed is measured to determine the flux angle which is a key variable in the control algorithm. The most popular way to measure the angular velocity is the use of rotary encoder. Since the errorneous measurement of rotor speed results in incorrect flux angle estimate, the control input generated based on the faulty information should be far from the desired (correct) value and deteriorates the overall control performance. In this paper the effects of encoder fault on motor variables and control performance are analyzed by both theoretical approach and experimental study. A parity equation based on the Power is suggested and applied to detect the incipient fault of encoder.

• Korean Journal of Optics and Photonics
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• v.5 no.3
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• pp.431-436
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• 1994

An automatic spectrorefractometer with a Littrow spectrometer arrangement has been designed and fabricated to measure the refractive indices of solids and liquids from the visible to the near IR. The achievable accuracy is numericaly analyzed by varying the measuring parameters and the electromechanical system for measuring the prism angle with a rotary encoder and a position sensitive detector is fabricated. The performance of the instrument is discussed in detail and the results of measurements are given. given.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.446-451
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• 1999

A study for the roundness of machining center is classified into two ways. one is the way that progresses the roundness amending the parameter of machining center based on the measured value after the measurement of the roundness of machining center by means of a existing measuring device, another is the way that measures the roundness by remodeling the existing measuring device. The former is studied by pack hei jae team in Seoul university, the latter is studied by TSUTSUMI. Especially TSUTSUMI measures the roundness according to circular compensation after the insertion of developed measuring desire using a rotary encoder to the spindle of machining tool. We study how regulation velocity occuring with circular motion of machining center table influences the roundness after measuring the roundness using Circular Test method by a 2 dimention probe and a standard discus in this experiment.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.75-81
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• 2000

This study for the roundness and perpendicularity of machining center is classified into two ways. One is the way that progresses the roundness amending the parameter of machining center based on the measured value after the measurement of the roundness of machaning center by means of a existing measuring device, another is the way that measures the roundness by remodeling the existing measuring device. the former is studied by pack hei jae team in Seoul university, the later is studied by TSUTSUMI. Especially TSUTSUMI measures the roundness according to circular compensation after the insertion of developed measuring device using a rotary encoder to the spindle of machining tool. we study how regulation velocity occuring with circular motion of machining center table influences the roundness after measuring the roundness using Circular Test method by a 2 dimention probe and a standard discus in this experiment.