인체의 연계작용을 고려한 프리텐셔너를 가진 시트벨트 시스템의 동역학 해석 및 실험적 검증

국민구,탁태오,박재순,김대희 대한기계학회 2007 環境管理學會誌 Vol.2007 No.5

To improve passenger safety, seatbelt systems with pre-tensioner that tightens seatbelt webbing using explosives just before collision are widely adopted. Even though seatbelt must not be unlatched without passenger's operation, release of a buckle due to explosion of pre-tensioner takes place in some situations resulting in serious injury to passengers. To prevent the unintended unlocking, a pendulum like part called anti-g mass is attached to the buckle to block displacement of release button. In this study, the unlocking conditions of anti-g buckle when pre-tensioner explodes has been theoretically investigated. Through multibody model of the seatbelt system incorporating every detailed part of the buckle, dynamic analysis of the seatbelt system with pre-tensioner has been performed including the driver's body model that interacts with seatbelt system. The simulations results has been validated through actual sled test with driver dummy and the seatbelt system.

Dynamic analysis of a PDP exhaust hole processing equipment considering glass substrate interaction

국민구,김래겸,탁태오 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.4

Exhaust hole drilling is one of the PDP (Plasma Display Panel) manufacturing processes to make about 1mm diameter holes for sucking out air in order to generate vacuum between two PDP glass substrates. In the drilling process, bigsized glasses about the size of a queen size bed are loaded, aligned, drilled, and unloaded, during which the dynamic interactions between glass and the handling equipment are very significant. To analyze exhaust hole drilling equipment dynamics, interaction with glass substrates that have somewhat different material properties from general glasses should be considered. The Young’s modulus and Poisson ratios of the substrates have been determined experimentally and verified via computation that simulates a well-known three-point bending test. Dynamic interaction of the glass with the handling equipment is modeled using a flexible glass and rigid body handling equipment models. The velocity profile by which the glasses are driven and the material properties of the handling equipment components contacting with the glasses are evaluated in view of the structural integrity of the glass and the operational efficiency of the equipment. The dynamic model is demonstrated to be an effective design tool for an exhaust hole drilling machine.

Dynamic Analysis of Seatbelt Systems with Anti-inertial Release Mechanisms

국민구,권상직,탁태오 한국자동차공학회 2008 International journal of automotive technology Vol.9 No.5

In order to prevent the uncontrolled release of seatbelt buckles due to high acceleration caused by pretensioners, anti-g buckles that have pendulum-shaped g-masses to block the releasing motion are commonly adopted in seatbelt systems. However, even with the wide applications of anti-g buckles, the underlying operational principles of anti-g buckles have yet to be investigated. This work studies conditions for the engagement of the g-mass to prevent inertial release, and conditions for maintaining a blocked state under very high acceleration. Using a multibody model of an anti-g buckle, the effects of various design parameters on the performance of the anti-g buckle have been examined. It turns out that design variables associated with the geometry of the g-mass and its contacting surface configuration play important roles. In order to account for the dynamic interaction between driver and seatbelt, a multibody model of a seatbelt system is combined with a dummy model to form a single dynamic system. Using the measured displacement of the buckle during the explosion of a pretensioner as the driving condition for simulation, dynamic analysis of the seatbelt with driver interaction has been carried out. Through comparison with measured and computed accelerations of webbing, which shows good agreement, the validity of the model has been demonstrated. The dynamic model for seatbelt and driver can be used as a design tool for the development of anti-g buckles. In order to prevent the uncontrolled release of seatbelt buckles due to high acceleration caused by pretensioners, anti-g buckles that have pendulum-shaped g-masses to block the releasing motion are commonly adopted in seatbelt systems. However, even with the wide applications of anti-g buckles, the underlying operational principles of anti-g buckles have yet to be investigated. This work studies conditions for the engagement of the g-mass to prevent inertial release, and conditions for maintaining a blocked state under very high acceleration. Using a multibody model of an anti-g buckle, the effects of various design parameters on the performance of the anti-g buckle have been examined. It turns out that design variables associated with the geometry of the g-mass and its contacting surface configuration play important roles. In order to account for the dynamic interaction between driver and seatbelt, a multibody model of a seatbelt system is combined with a dummy model to form a single dynamic system. Using the measured displacement of the buckle during the explosion of a pretensioner as the driving condition for simulation, dynamic analysis of the seatbelt with driver interaction has been carried out. Through comparison with measured and computed accelerations of webbing, which shows good agreement, the validity of the model has been demonstrated. The dynamic model for seatbelt and driver can be used as a design tool for the development of anti-g buckles.

타이어에 따른 차량 승차감의 객관 평가와 주관 평가의 상관관계

국민구(Mingu Kuk),김봉수(Bongsu Kim),성기득(Kideug Sung),신영동(Youngdong Shin),정철호(Cheolho Jeong) 한국자동차공학회 2011 한국자동차공학회 부문종합 학술대회 Vol.2011 No.5

The vehicle ride comfort is one of the most important performances in the automotive industry. The vehicle ride comfort is rated as SAE subjective assessment by professional test driver. But, subjective assessment is lack of objectivity. So recently objective assessment has been used in researching in the areas of the vehicle ride comfort. In this study, a passenger car is driven at several tires, vehicle speeds, road profiles. And objective assessment method for the vehicle ride comfort test is constructed. First, the triaxial accelerometers are mounted on the knuckle, floor, seat, seat-back and are measured by twelve accelerations. And the measured accelerations express one ride comfort value according to Human Vibration of ISO 2631-1 and BS6841. Correlations are determined between objective ride comfort value and subjective rating.

유리의 동특성을 고려한 기판 레이저 배기홀 가공 장비의 동역학 해석

국민구(Min-Gu Kuk),탁태오(Tea-Oh Tak),김대희(Dae-Hee Kim) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.11

PDP glass handling system that can handle large size glass fast and accurately is needed in many PDP manufacturing equipments to improve productivity. For exhaust hall drilling equipments that use laser power instead of conventional mechanical drill, more care should be taken in handling the glass due to the holes in the glass. To a predict dynamics of glass handling equipment accurately, interactive analysis that includes both glass and handling mechanisms are required. Due to high brittleness of PDP glass, its material properties such as Young's modulus and Poisson's ratio should be determined through some experimental procedures such as 3 point bending test. The FEM model of the glass was combined to the glass handling mechanism that can interactively analyze elastic behavior of glass under the action of handling mechanism. The impact forces, stress, deflections of the glass was calculated at loading and aligning stages of exhaust hall drilling. This glass and mechanism model can be used to improve design of various glass handling mechanisms.

프리텐셔너가 장착된 시트벨트 시스템의 관성잠김 안전버클 개발

국민구(Min-Gu Kuk),탁태오(Tea-Oh Tak),박재순(Jae-soon Park),신승언(Seung-Eon Shin),김대희(Dae-Hee Kim),김종각(Jong-Kag Kim),유병개(Byoung-Gae You),김철현(Chul-Hyun Kim) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.6

To improve passenger safety, seatbelt systems with pre-tensioner that tightens seatbelt webbing using explosive just before collision are widely used these days. Even though seatbelt must not unlatched without passenger's operation, explosive power of pre-tensioner can cause unlocking of a buckle. To prevent the unlocking, an Anti-g mass that blocks displacement of the release button has been attached to the buckle. In this study, the dynamics and statics of locking mechanism associated with operation of Anti-g buckle has been theoretically investigated, and important design variables that affect the operation of Anti-g buckle have been identified. Through the total seatbelt system's dynamic simulation using force and displacement inputs obtained from seatbelt sled test, design of the proposed Anti-g buckle has been validated.

인체의 연계작용을 고려한 프리텐셔너를 가진 시트벨트 시스템의 동역학 해석 및 실험적 검증

국민구(Min-Gu Kuk),탁태오(Tea-Oh Tak),박재순(Jae-Soon Park),김대희(Dae-Hee Kim) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.5

To improve passenger safety, seatbelt systems with pre-tensioner that tightens seatbelt webbing using explosives just before collision are widely adopted. Even though seatbelt must not be unlatched without passenger's operation, release of a buckle due to explosion of pre-tensioner takes place in some situations resulting in serious injury to passengers. To prevent the unintended unlocking, a pendulum like part called anti-g mass is attached to the buckle to block displacement of release button. In this study, the unlocking conditions of anti-g buckle when pre-tensioner explodes has been theoretically investigated. Through multibody model of the seatbelt system incorporating every detailed part of the buckle, dynamic analysis of the seatbelt system with pre-tensioner has been performed including the driver's body model that interacts with seatbelt system. The simulations results has been validated through actual sled test with driver dummy and the seatbelt system.

프리텐셔너가 장착된 시트벨트 시스템의 관성잠김 안전버클 개발

탁태오,국민구,김대희,박재순,신승언,최석 강원대학교 산업기술연구소 2006 産業技術硏究 Vol.26 No.B

To improve passenger safety, seat belt systems with pre-tensioner that tightens seat belt webbing using explosive just before collision are widely used these days. Even though seatbelt must not unlatched without passengers' operation. explosive power of pre-tensioner can cause unlocking of a buckle. To prevent the unlocking, an anti-g mass that blocks displacement of the release button has been attached to the buckle. In this study, the dynamics and statics of locking mechanism associated with operation of anti-g buckle has been theoretically investigated, and important design variables that affect the operation of anti-g buckle have been identified. Through the total seat belt system's dynamic simulation using force and displacement inputs obtained from seat belt sled test, design of the proposed anti-g buckle has been validated.

프리텐셔너가 장착된 시트벨트 시스템의 관성잠김 안전버클 개발

탁태오,국민구,김대희,박재순,신승언,최석 강원대학교 산업기술연구소 2006 産業技術硏究 Vol.26 No.A

To improve passenger safety, seat belt systems with pre-tensioner that tightens seat belt webbing using explosive just before collision are widely used these days. Even though seatbelt must not unlatched without passengers' operation. explosive power of pre-tensioner can cause unlocking of a buckle. To prevent the unlocking, an anti-g mass that blocks displacement of the release button has been attached to the buckle. In this study, the dynamics and statics of locking mechanism associated with operation of anti-g buckle has been theoretically investigated, and important design variables that affect the operation of anti-g buckle have been identified. Through the total seat belt system's dynamic simulation using force and displacement inputs obtained from seat belt sled test, design of the proposed anti-g buckle has been validated.

모터구동형 안전벨트 리트랙터의 구동 메커니즘 설계

탁태오,박재순,국민구,김대희,신승언,최석 강원대학교 산업기술연구소 2006 産業技術硏究 Vol.26 No.B

Motorized retractors enhance the safety of passengers by removing the slack of webbing and by holding upright driving position. Reliability of a driving mechanism that includes one-way clutch between the driving motor and webbing is directly linked to the safety of passenger. In this research, conditions for locking one-way clutch. and also conditions for sustaining locking are theoretically investigated. The operation of a motorized retractor under realistic conditions is simulated in order to validate the proposed retractor design.