• 제목/요약/키워드: Radial error

Search Result 274, Processing Time 0.027 seconds

Precision Measurement System forBall Screw Pitch Error (볼스크류 전구간 피치오차 측정시스템)

  • 박희재;김인기
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1993.10a
    • /
    • pp.279-285
    • /
    • 1993
  • This paper presents a precision automatic measuring system for ball screw Pitch. Ball screw is mounted on a precision indexing table, and the ball screw pitch is measured via magnetic scale, where the indexing and measurement are performed by a PC. For precision indexing of ball screw, direct driven motor is coupled to the designed dead and live centers; the performance of the centers are assessed with a precision master sylinder,such as radial motion,tilt motion, and axial motions. An error compensation model is constructed for the measurement system of ball screw pitch, where the error motions of indexing system as well as the scale measurement system are combined to give the measurement error for the ball screw. The developed system proposes an automated precision measurement system for manufacturers and users of ball screw.

  • PDF

Direct Measurement of Spindle Motion Error Using a Regular Crystalline Lattice and a Scanning Tunneling Microscope

  • Chaikool, Patamaporn;Aketagawa, Masato;Okuyama, Eiki
    • International Journal of Precision Engineering and Manufacturing
    • /
    • v.9 no.4
    • /
    • pp.11-15
    • /
    • 2008
  • Metrology tools with the ability to measure spindle motion error on the order of a nanometer are required due to recent advances in nanotechnology. We propose a direct measurement method for the radial motion error of a precision spindle using a regular crystalline lattice and a scanning tunneling microscope (STM). A highly oriented pyrolytic graphite (HOPG) crystal combined with an STM is used as a two-dimensional reference scale. The measurement principle and the preliminary experimental results are discussed in this article. The preliminary experimental results demonstrated that the proposed method has the capability to incorporate a two-dimensional encoder to measure the spindle motion error.

A Study on YHB RDF via Density Dependent Pressure Calculation of Ethene Gas (Ethene 기체의 밀도변화에 따른 압력 계산에 의한 YHB 동경분포함수에 대한 연구)

  • Yoon, Jong Ho;Kim, Hae Won
    • Applied Chemistry for Engineering
    • /
    • v.9 no.4
    • /
    • pp.561-564
    • /
    • 1998
  • The radial distribution functions of a linear spheroidal type gas molecule $C_2H_4$ were calculated by using the Stockmayer molecular molel, which assumed the $C_2H_4$ molecule as simple quadrupolar molecule. To examine the validity of the calculated radial distribution of $C_2H_4$ gas, the density dependent pressures of $C_2H_4$ gas at several temperatures were calculated and compared with literarily known experimental pressure data of $C_2H_4$ gas. The temperatures examined was 50, 100 and $150^{\circ}C$ and the densities were up to $0.02/{\AA}^3$ (maximum pressure = 1500 atm). The radial distribution function expression used was derived by Yoon, Hacura, and Baglin (YHB) with Baker and Henderson's perturbation theory. The calculated results by a computer showed that the $C_2H_4$ pressures calculated agreed well with the experimental values within ${\pm}5%$ of error range. This indicated that the YHB radial distribution function expression is good enough to obtain various physical quantities sensitive to density such as pressure with resonable accuracy.

  • PDF

Performance comparison of SVM and ANN models for solar energy prediction (태양광 에너지 예측을 위한 SVM 및 ANN 모델의 성능 비교)

  • Jung, Wonseok;Jeong, Young-Hwa;Park, Moon-Ghu;Lee, Chang-Kyo;Seo, Jeongwook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2018.10a
    • /
    • pp.626-628
    • /
    • 2018
  • In this paper, we compare the performances of SVM (Support Vector Machine) and ANN (Artificial Neural Network) machine learning models for predicting solar energy by using meteorological data. Two machine learning models were built by using fifteen kinds of weather data such as long and short wave radiation average, precipitation and temperature. Then the RBF (Radial Basis Function) parameters in the SVM model and the number of hidden layers/nodes and the regularization parameter in the ANN model were found by experimental studies. MAPE (Mean Absolute Percentage Error) and MAE (Mean Absolute Error) were considered as metrics for evaluating the performances of the SVM and ANN models. Sjoem Simulation results showed that the SVM model achieved the performances of MAPE=21.11 and MAE=2281417.65, and the ANN model did the performances of MAPE=19.54 and MAE=2155345.10776.

  • PDF

Development of Automatic Cam Profile Measurement System (자동 측정이 가능한 전용 캠 프로파일 측정 시스템 개발)

  • Jeong, Hwang-Young;Lee, Hyun-Seok;Park, Tae-Min;Shin, Woo-Cheol;Koh, Jun-Bin;Hong, Jun-Hee
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.17 no.1
    • /
    • pp.106-112
    • /
    • 2008
  • In this paper, It does the profile measurement of the cam of diesel engine SOHC of the actual object. It uses the measurement of run-out method. This method is that the surface of the object is measured by the sensor when the object rotate, and calculated and displayed by the computer the signal which acquired by sensor. When we acquire the signals, we have two error because of motion and contacting between cam and probe. In this paper, we compensate the motion error while simply liner equation. And we have a solution that we change the figure of probe when we have a contacting error. We compared the data measuring on developed automatic cam profile measuring system with the data measured on CMM.

An Error Motion Analysis of Rotary Stage Driven By PZT (PZT로 구동되는 회전 스테이지의 오차 운동 분석)

  • Kim, Jin-Ho;Shin, Dong-Ik;Yun, Deok-Won;Han, Chang-Soo;Lee, Sang-Moo;Nam, Kyung-Tae
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.17 no.1
    • /
    • pp.132-136
    • /
    • 2008
  • Axis of rotation error on rotary system are significant; such as the spindle radial error motion of a aligner, wire bonder and inspector machine which results in the poor state of manufactured goods. In this paper, the simple stage which consists of one PZT actuator and rotary encoder, is analyzed and measured by high resolution capacitance type displacement sensor. As the result of experiment, the paper discusses several issues that must be considered when designing rotary stage driven by PZT.

Accuracy Evaluation and Enhancement of Machine Tools Using a Kinematic Ball Bar (기구볼바를 이용한 가공기계의 정밀도 평가 및 향상 기술 개발)

  • Moon, J.H.;Pahk, H.J.;Chu, C.N.
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.13 no.6
    • /
    • pp.114-121
    • /
    • 1996
  • This paper presents an useful technique for assessing the volumetric errors in multi-axis machine tools using the kinematic double ball bar. This system has been developed based on the volumetric error map which describes the 3 dimensional errors of machine tools. The developed system inputs the measured radial data of 3 different planes, respectively XY,YZ,ZX, analysing the volumetric errors such as positional. straightness, angle, and squareness errors, etc. The developed system has been tested in a practical machine tool, and showed high potential for the error assessment of multi-axis machine tools.

  • PDF

Developement of Measuring Units of circular Motion Accuracy on NC Lathe (NC선반의 원 운동정도 측정장치의 개발)

  • 김영석;김재열
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.10 no.6
    • /
    • pp.1-7
    • /
    • 2001
  • It is very important to test circular motion accuracy of NC machine tools as it affects all other machines machined by them in industries. In this paper, it has become possible to detect errors of linear displacement of radial directions for circle tar motion accuracy test using newly assembled magnetic type of linear scale so called Magnescale ball-bar system. It has also organized computer program systems using tick pulses come out from computer for getting error motion data at colt start time interval in circular motion test on NC lathe. Error data gotten from test is expressed to plots and analysed to numerics by various statistical treatments.

  • PDF

Quality Check Monitoring System for Advancing the Yield Rate based on Sensor (베어링 생산수율 향상을 위한 센서기반 품질 체크 모니터링 장치)

  • Xiang, Zhao;Yoon, Dal-Hwan
    • Journal of IKEEE
    • /
    • v.23 no.1
    • /
    • pp.22-28
    • /
    • 2019
  • This paper presents the monitoring method of machining error and quality check to improve the productivity of boring manufacturing process. Machining error usually appears as the offset of spatial location of actual cutting path compared to ideal cutting path. In order to monitor an error of workpiece, multiple factors affecting quality of boring, such as distortion of workpiece, clamping error, radial rotation error of the spindle and motion error of machine tools, were took into account. To verify the productive quality, we propose the quality check system. The system based on IT convergence analyzes the process error rate and saves the analyzed data in memory. Also, these play important roles in detecting an inferior production goods and can decrease the production cost and loss of bearing.