Structural Optimization of the Lower Parts in a Humanoid Considering Dynamic Characteristics

동적 특성을 고려한 휴머노이드 하체 부품의 구조최적설계

  • 홍을표 (한양대학교 대학원 기계공학과) ;
  • 이일권 (삼성엔지니어링 기술본부) ;
  • 유범재 (한국과학기술연구원 인지로봇연구단) ;
  • 김창환 (한국과학기술연구원 인지로봇연구단) ;
  • 박경진 (한양대학교 기계정보경영공학부)
  • Published : 2008.10.01


A humanoid is a robot with its overall appearance based on that of the human body. When the humanoid moves or walks, dynamic forces act on the body structure. Although the humanoid keeps the balance by using a precise control, the dynamic forces generate unexpected deformation or vibration and cause difficulties on the control. Generally, the structure of the humanoid is designed by the designer's experience and intuition. Then the structure can be excessively heavy or fragile. A humanoid design scenario for a systematic design is proposed to reduce the weight of the structure while sufficient strength is kept. Lower parts of the humanoid are selected to apply the proposed design scenario. Multi-body dynamics is employed to calculate the external dynamic forces on the parts and structural optimization is carried out to design the lower parts. Because structural optimization using dynamic forces directly is fairly difficult, linear dynamic response structural optimization using equivalent static loads is utilized. Topology and shape optimizations are adopted for two steps of initial and detailed designs, respectively. Various commercial software systems are used for analysis and optimization. Improved designs are obtained and the design results are discussed.


Humanoid;Structural Optimization;Equivalent Static Load;Multibody Dynamics


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