• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2007.05a
• /
• pp.859-865
• /
• 2007

This paper presents a method to analyze the unbalance response of a high speed polygon mirror scanner motor supported by sintered bearing and flexible supporting structures by using the finite element method and the mode superposition method. The appropriate finite element equations for polygon mirror are described by rotating annular sector element using Kirchhoff plate theory and von Karman non-linear strain, and its rigid body motion is also considered. The rotating components except for the polygon mirror are modeled by Timoshenko beam element including the gyroscopic effect. The flexible supporting structures are modeled by using a 4-node tetrahedron element and 4-node shell element with rotational degrees of freedom. Finite element equations of each component of the polygon mirror scanner motor and the flexible supporting structures are consistently derived by satisfying the geometric compatibility in the internal boundary between each component. The rigid link constraints are also imposed at the interface area between sleeve and sintered bearing to describe the physical motion at this interface. A global matrix equation obtained by assembling the finite element equations of each substructure is transformed to a state-space matrix-vector equation, and both damped natural frequencies and modal damping ratios are calculated by solving the associated eigenvalue problem by using the restarted Arnoldi iteration method. Unbalance responses in time and frequency domain are performed by superposing the eigenvalues and eigenvectors from the free vibration analysis. The validity of the proposed method is verified by comparing the simulated unbalance response with the experimental results. This research also shows that the flexibility of supporting structures plays an important role in determining the unbalance response of the polygon mirror scanner motor.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2021.07a
• /
• pp.495-496
• /
• 2021

코로나 19로 인하여 다중이용시설에 출입 시 정부 지침에 따라 QR코드 스캔, 출입 명부 작성, 체온 측정 등 방역절차를 지켜야한다. 본 연구에서는 방역 절차를 간편화하고 동합한 방역 시스템을 제안한다. QR코드 스캐너를 통하여 출입자의 신상 정보를 확인하며 체온 측정 모듈을 통하여 출입자의 체온을 측정한다. 추가적으로 워터펌프를 통하여 소독제를 분사하며 서보모터를 통하여 출입문을 열고 닫는다. 또한, 산업 현장에서는 알코올 측정 센서를 통하여 작업자의 알코올 수치를 측정하여 음주로 인한 산업사고도 예방한다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2017.04a
• /
• pp.12-12
• /
• 2017

본 연구에서는 롤러식 양파 파종기의 작동 특성 파악을 위한 동적 시뮬레이션을 수행하였다. 롤러식 양파 파종기의 주요부는 롤러와 포트트레이로 구성된다. 양파 파종기의 작동 특성 파악을 위해 동력전달 경로의 구성요소와 각 주요부의 속도를 분석한 결과 동력원인 모터의 출력은 체인과 스프라켓을 통해 포트트레이와 롤러에 전달되며 모터에서의 회전속도는 1770rpm으로 감속기를 통해 출력축의 회전속도는 17.7rpm으로 감소한다. 이론적으로 도출한 포트트레이의 이동속도는 74.98mm/s, 롤러의 회전속도는 22.13rpm으로 나타났다. 시뮬레이션을 수행하기 위해 스캐너를 이용하여 롤러식 파종기를 실측했으며 후에 3D모델링을 진행하였다. 시뮬레이션 해석조건은 파종기의 실제 작동방식을 고려하여 롤러1과 3은 포트트레이와 면대면 접촉을 통해 회전하도록 설정하였고 롤러2와 롤러4는 동력전달경로에 포함된 스프라켓과 기어의 잇수비를 반영하여 회전속도를 도출하여 적용하였다. 시뮬레이션 결과 롤러의 회전속도는 모두 22.13rpm으로 수식에 근거하여 도출한 값과 계측 값이 같음을 확인하였다. 또한 파종 깊이를 결정하는 요소인 롤러의 상토 압축 정도를 파악하기 위하여 롤러궤적 시뮬레이션을 통해 롤러 끝 단의 궤적을 분석하였는데 롤러궤적 분석 결과 롤러의 끝 단은 약 9.8mm 깊이로 내려가는 것을 확인하였다.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.854-855
• /
• 2015

Electric machines for office automation device such as printer and scanner have been required the low noise and vibration performance. Many researches about the low noise and vibration of polygon mirror scanner motor have been also progressed. The noise and vibration of polygon mirror scanner motor can be classified by aerodynamic, structural and electromagnetic. Electromagnetic noise and vibration can be occurred by high cogging torque and nonsinusoidal back EMF. To improve the cogging torque and back EMF characteristic, we apply unequal air-gap. To analyse characteristic of a polygon mirror scanner motor, two dimensional finite element method is used. To minimize the cogging torque of a polygon mirror motor, Kriging based on latin hypercube sampling (LHS) is utilized. As a result, the cogging torque and torque ripple improved while maintaining the back EMF and average torque.

• Proceedings of the KIEE Conference
• /
• 2005.10c
• /
• pp.118-121
• /
• 2005

The claw-pole PM(Permanent Magnet) stepping motor has the advantage of the positioning machine because of a relatively little step angle, facility of control, and detent torque characteristics. Although the research about this motor has been progressed, it was difficult to analyze because of three-dimensional magnetic circuit. This paper proposed a design method of the claw-pole PM stepping motor using 3D-FEA. We established design variables that have an important effect upon the characteristics of the motor, and then peformed analysis of the static and the dynamic characteristics. We also manufactured the test products and practiced the performance tests for verification of the analysis results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2008.11a
• /
• pp.394-400
• /
• 2008

This paper presents an analytical method to investigate the stability of FDBs (fluid dynamic bearings) considering the tilting motion. The perturbed equations of motion are derived with respect to translational and tilting motion for the general rotor-bearing system with five degrees of freedom. The Reynolds equations and their perturbed equations are solved by using the FEM in order to calculate the pressure, load capacity, and the stiffness and damping coefficients. This research introduces the radius of gyration to the equations of notion in order to express the mass moment of interia with respect to the critical mass. Then the critical mass of FDBs is determined by solving the eigenvalue problem of the linear equations of motion. This research is numerically validated by comparing the stability chart of FDBs with the time response of the whirl radius obtained from the direct integration of the equations of motion. This research shows that the tilting motion is one of the major design considerations to determine the stability of rotating system. It also shows that the stability of FDBs considering only translation is overestimated in comparison with the stability of FDBs considering both translational and tilting motion.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.6 no.3
• /
• pp.470-474
• /
• 2002

The graylevel image scanning system realization and design using CIS(Contact image Scanning)be amenable to recognize a papers, OMR and OCR sheet is proposed. The design technique is used CIS scanning sensor in fixing step motor and is optimized with DSP processor for inage processing, and transfer input image data par line in feeding a step unit to PC on the USB interfacer. This system is portable ad A4 size scanning. and keeps image scan processing speed 300mm/sec. The recognition percentage has 98% on the OCR and bar codes.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.38 no.2
• /
• pp.27-32
• /
• 2001

In this paper, the three dimension scanner system employing the parallel camera model is discussed. The camera calibration process and the three dimension scanning algorithm are developed. The laser strip line is utilized for assisting stereo matching. An object being scanned rotates on the plate which is activated by a stepping motor, The world coordinate which is. the measured distance from the camera to the object is converted into the model coordinate. The facets created from the point. cloud of the model coordinate is used for rendering the scanned model by using the graphic library such as OpenGL. The unmatched points having no validate matching points are interpolated from the validate matching points of the vicinity epipolar lines.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2002.05a
• /
• pp.581-584
• /
• 2002

The graylevel image scanning system realization and design using CIS(Contact Image Scanning)be amenable to recognize a papers, OMR and OCR sheet is proposed. The design technique is used CIS scanning sensor in fixing step motor and is optimized with DSP processor for image processing., and transfer input image data par line in feeding a step unit to PC on the USB interfacer. This system is portable and A4 size scanning and keeps image scan processing speed 300mm/sec The recognition percentage has 98% on the OCR and bar codes.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.18 no.6
• /
• pp.1189-1196
• /
• 2023

Due to the acceleration of urbanization and advancements in technology, the importance of information related to indoor spaces has been increasing. Various scanning technologies are being developed to enable versatile utilization of the interior of buildings. In this paper, a system is proposed that utilizes 2D LIDAR for scanning, rotating, and moving LIDAR in the vertical direction to obtain a collection of 2D data, which is then aggregated to acquire 3D indoor spatial information. Finally, algorithms, including error correction, are applied to visualize the indoor structure in three dimensions and generate an output.