• Title/Summary/Keyword: Hole Deformation

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Robotic Assembly Using Configuration and Force/Torque Information of Tactile Sensor System (접촉센서의 형상과 힘/토크 정보를 이용한 로봇조립)

  • 강이석;김근묵;윤지섭;조형석
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.12
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    • pp.2315-2327
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    • 1992
  • A robot assembly method which uses configuration and force/torque information of tactile sensor system and performs chamferless peg-in-hole tasks is suggested and experimentally studied. When the robot gripes the peg with random orientation, the realignment of the peg to the hole center line is successfully performed with the gripping configuration information of the tactile sensor and the inverse kinematics of the robot. The force/torque information of the tactile sensor makes it possible to control the contacting force between mating parts during hole search stage. The suggested algorithm employs a hybrid position/force control and the experiments show that the algorithm accomplishes well peg-in-hole tasks with permissible small contacting force. The chamferless peg-in-hole tasks with smaller clearance than the robot repeatibility can be excuted without any loss or deformation of mating parts. This study the possibility of precise and chamferless parts mating by robot and tactile sensor system.

A Study on the Distortion of a Thin Plate Panel by Laser Welding (레이저용접에 의한 박판구조물의 용접변형 해석에 관한 연구)

  • Kim, Choong-Gi;Kim, Jae-Woong;Kim, Ki-Chul
    • Journal of Welding and Joining
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    • v.25 no.1
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    • pp.49-56
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    • 2007
  • Prediction and control of the thermal distortion is particularly important for the design and manufacture of welded thin plate panel. In this study, experiments and computations are performed to analyze effect of a hole configuration and a specimen size on distortion. In addition, this study aims to develop a thermal elasto-plastic simulation using finite element method to predict distortion, with particular emphasis on buckling deformation generated in plates welded around hole. From the experiments, the severe distortion appeared in the weldments by the laser welding process, in which the specimen size plays an important role on the distortion but the hole configuration showed little effect. And the results of numerical analysis were corresponded well with the experiment ones. Thus, a thermal elasto-plastic analysis model for predicting the weld distortion of thin plate panel was successfully developed through this study.

Physical drying and frying characteristics of kimbugaks made by a pasting & garnishing machine (풀칠·고명기로 제조된 김부각의 물리적 건조 및 튀김 특성)

  • Yoo, Soo-Nam;Choi, Yeong-Soo
    • Korean Journal of Agricultural Science
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    • v.42 no.4
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    • pp.439-446
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    • 2015
  • Kimbugak is one of Korea's traditional snacks made of laver. This study was conducted to investigate the physical drying and frying characteristics of kimbugaks made by a pasting & garnishing machine. The drying and frying characteristics should be analyzed to develop a continuous operation system for manufacturing kimbugak because kimbugak has a high moisture content after pasting process. Materials for pasting and garnishing on laver were rice gruel and sesame. The aluminum shelf with square hole was selected as a drying shelf. The recommended size of the square hole type was $1.5mm{\times}1.5mm$ because characteristics of deformation and easy separation from the shelf were excellent at the hole size. The drying time of 2 hours was also recommended with the drying temperature of $70^{\circ}C$ based on the test results such as dried condition (good), moisture conten t (3.7%), deformation (12.1 mm), and shrinkage rate (19.8%). As the frying conditions for dried kimbugaks, recommended oil temperature and frying time were $170^{\circ}C$, 15 seconds, respectively when corn oil was used. In the case of frying for undried kimbugaks, recommended oil temperature and frying time were $210^{\circ}C$, 2 - 3 minutes, respectively for improvement of work efficiency.

A Study on the Cam Ring Deformation in a Balanced Type Vane Pump (유압 베인 펌프의 캠 링 변형에 관한 연구)

  • 조명래;한동철;양광식;박제승;최상현
    • Tribology and Lubricants
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    • v.14 no.3
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    • pp.59-64
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    • 1998
  • This paper presents the deformation characteristics of cam ring in a balanced type vane pump. Cam ring is operated in the high-pressure condition. Therefore the local deformation of cam ring affects the characteristics of compression, vane motion and noise and vibration. We analyzed the deformation of cam ring for the three types by using the finite element method. The deformed shape of cam ring and the effects of deformation on the compression are presented. As a result of analysis, we know that the right hole of the cam ring has advantage for reducing the pressure overshoot.

Structural Safety Analysis on Crack Propagation in Compact Tension Specimen (소형 인장 시험편 내의 크랙 전파에 대한 구조 안전해석)

  • Cho, Jae-Ung
    • Journal of the Korea Convergence Society
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    • v.5 no.1
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    • pp.23-27
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    • 2014
  • In case eccentric load is applied at compact tension specimen, the propagation behavior due to existence or nonexistence of hole, numbers and positions of holes near crack is investigated in this study. Strain energy, displacement and stress happened in specimen are examined through simulation analysis. And stress intensity factor is obtained by the basis of strain energy and deformation. When defect or hole exists in structure, the possibility of fracture can be thought to be verified by using the study result.

Study on Mechanism of Burr Formation in Drilling (드릴가공시 버 형성에 관한 연구)

  • 이징구;고성림;고대철
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.11a
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    • pp.823-826
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    • 2000
  • Burr formed in drilling are classified into three types. no burr, burrs with cap, teared burr. To control burr size in drilling. the second type burrs with cap are to be formed because it is small and uniform. It is necessary to understand the mechanism of cap formation to derive the burr formation into second type burr with cap. In several materials, second type burrs are formed in drilling by changing cutting conditions. It is observed that cap is formed as a result of the plastic deformation along the outside of exit hole. According to the tension behavior of the material in concentrated region between hole and drill outside edge, the geometry of burr with cap is determined.

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Free vibration analysis of laminated composite beam under room and high temperatures

  • Cunedioglu, Yusuf;Beylergil, Bertan
    • Structural Engineering and Mechanics
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    • v.51 no.1
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    • pp.111-130
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    • 2014
  • The aim of this study is to investigate the effects of the beam aspect ratio(L/h), hole diameter, hole location and stacking layer sequence ($[0/45/-45/90]_s$, $[45/0/-45/90]_s$ and $[90/45/-45/0]_s$) on natural frequencies of glass/epoxy perforated beams under room and high (40, 60, 80, and $100^{\circ}C$) temperatures for the common clamped-free boundary conditions (cantilever beam). The first three out of plane bending free vibration of symmetric laminated beams is studied by Timoshenko's first order shear deformation theory. For the numerical analyses, ANSYS 13.0 software package is utilized. The results show that the hole diameter, stacking layer sequence and hole location have important effect especially on the second and third mode natural frequency values for the short beams and the high temperatures affects the natural frequency values significantly. The results are presented in tabular and graphical form.

The Finite Element Analysis of the Mandrel Shape's Influence on the Residual Stress Distribution by Cold Expansion Method (형상봉의 모양이 홀확장 잔류응력 분포에 미치는 영향에 대한 유한요소해석)

  • Jang, Jae-Soon;Cho, Myoung-Rae;Yang, Won-Ho
    • Journal of the Korean Society for Precision Engineering
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    • v.23 no.9 s.186
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    • pp.127-133
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    • 2006
  • Cold expansion method is used to protect a fatigue fracture from fastener hole in the structure and aerospace industry. Cold expansion is that an oversized tapered mandrel goes through the hole and produces a compressive residual stress as well as plastic deformation around the hole. Here, mandrel shapes are one of the factors which are influenced on the residual stress distribution by cold expansion method. This paper, according to mandrel shapes (diameter of mandrel, length of mandrel and length of taper), we are performed a finite element analysis of residual stress distribution by cold expansion method. From this study, it has been found that diameter of mandrel and length of taper are an important factor which was generated a low compressive residual stress surround of fastener hole by cold expansion method.

Study on Deformation Characteristics of Hole Expansion Test and Its Applicability (구멍확장시험의 변형특성 및 활용성 연구)

  • Han, S.S.;Lee, H.Y.
    • Transactions of Materials Processing
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    • v.28 no.3
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    • pp.154-158
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    • 2019
  • The hole expansion tests using conical punch, flat punch or hemispherical punch are widely used for stretch flangeability verification of HSS. In this study, we investigate the strain distribution on the shear edges of the hole expansion test using grid marking and a projector. A small crack at the edge is distributed, resulting in a large gap between the HER and the crack strain. The strain distribution at the edges is irregular due to anisotropy of sheet metal. While an edge perpendicular to the rolling direction indicate a lower strain level compared to an edge parallel to the rolling direction, edge cracks occur at the edge perpendicular to the rolling direction. To predict the manifestation of edge cracks in FE analysis, the result of the hole expansion test with a crack strain measurement may well be a better tool than FLD. In this case, the level of strain and the direction of the edge relative to the rolling direction should be well considered.

A Study on the Distortion of a Laser Welded Sheet Metal Structure (박판 레이저용접구조물의 용접변형 해석에 관한 연구)

  • Kim, Chung-Gi;Kim, Jae-Ung;Kim, Gi-Cheol
    • Proceedings of the KWS Conference
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    • 2006.10a
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    • pp.280-282
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    • 2006
  • Prediction and control of the thermal distortion is particularly important for the design and manufacture of welded thin plate panel. In this study, experiments and computations are peformed to analyze how hole configuration and the size of the specimen effect on distortion. In addition, this study aims to develop a thermal elasto-plastic simulation using finite element method to predict distortion, with particular emphasis on buckling deformation generated in attachments welded around hole.

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