• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2003년도 추계학술대회
• /
• pp.1775-1780
• /
• 2003

A hybrid finite element analysis was used to analyze the influence of ring gear rim thickness and spline number on the static properties of an epicyclic gear system with manufacturing errors. Both of these parameters affected the bearing force and critical stress. The effect of changes in the rim thickness on the load sharing between the gears depended on the type of manufacturing error. Ring flexibility improved the load sharing between planetary gears only in systems with planet tooth thickness or planet tangential errors; for other types of error, ring flexibility worsened the load sharing. To improve load sharing, rim thickness and spline number should be controlled within a specific range. The effect of the ring gear boundary condition was more apparent in a system with errors than in a normal system.

• 대한기계학회논문집A
• /
• 제27권9호
• /
• pp.1597-1606
• /
• 2003

Static analysis using hybrid finite element(FE) method has been applied to characterize the influence of position, runout and thickness errors of the sun, ring and planet on the bearing forces and critical tooth stress. Some guidelines for tolerance control to manage critical stress and bearing forces are deduced from the results. Carrier indexing error planet assembly and planet tooth thickness error are most critical to reduce planet bearing force and maximize load sharing as well as to reduce critical stresses. Sun and carrier bearing forces due to errors increase several times more than those of normal condition.

• 대한기계학회논문집A
• /
• 제27권11호
• /
• pp.1949-1957
• /
• 2003

A hybrid finite element analysis was used to analyze the influence of ring gear rim thickness and spline number on the static properties of a planetary gear system with manufacturing errors. Both of these parameters affected the bearing force and critical stress. The effect of changes in the rim thickness on the load sharing between the gears depended on the type of manufacturing error. Ring flexibility improved the load sharing between planetary gears only in systems with planet tooth thickness or planet tangential errors; for other types of error, ring flexibility worsened the load sharing. To improve load sharing, rim thickness and spline number should be controlled within a specific range. The minimum rim thickness limit should be determined considering not only the critical stress but also the load sharing. The effect of the ring gear boundary condition was more apparent in a system with errors than in a normal system.

• 한국정밀공학회지
• /
• 제23권7호
• /
• pp.168-176
• /
• 2006

Nowadays, Three dimensional printing (3DP) technique that is one of solid freeform fabrication (SFF) technology has been notable issue, and has been applied by various fields. The SFF system can fabricate three dimensional objects of solid freeform with high speed and low cost using ink jet printing technology. In this research, a SFF system to analyze 3DP process technology is developed. We applied sliding mode control with sliding perturbation observer (SMCSPO) algorithm and minimized position error to the developed SFF system. We analyzed and optimized process variables such as jetted volume, layer thickness, powder bed and so on experimentally. Also. the dimensional error of a developed SFF system is evaluated. Finally, the feasibility of application to bio manufacturing is presented through successful fabrication of teeth and cranium model.

• 산업식품공학
• /
• 제14권1호
• /
• pp.75-79
• /
• 2010

시중 즉석 면류의 관능적 성질과 back extrusion test 데이터에 대하여 partial least square regression(PLSR)을 실시하였다. 즉석유탕면 8종과 즉석비유탕면 2종에 대한 관능적 속성으로서 경도(A), 탄성(B), 껄끄러운 정도(C), 이에 박히는 정도(D), 굵기감(E)를 검사하였고, 실험 데이터로 힘-변형 곡선 전체를 사용하였다. PLSR의 회귀계수는 힘-변형곡선의 압착단계, 항복단계, 압출단계로 크게 구분되어 각관능속성에 대한 특유의 양 또는 음의 효과를 나타냈다. PLSR의 상관계수는 E>D>A>B>C, 오차(root mean square error of prediction expressed in sensory units)는 D>C>E>B>A, 예측능(relative ability of prediction)는 D>C>E>B>A 로 나타나 종합적으로 '이에 박히는 정도'가 PLSR의 적용에 가장 우수하게 나타났다. '경도'는 예측능은 낮았지만 상관성은 높아서 시료간 순위의 결정에 합당하게 평가되었다.