轮轨接触应力对轮轨磨耗和滚动接触疲劳影响较大，因此精确计算轮轨接触点与接触应力非常重要。本文基于重载铁路轮轨标准型面，利用改进的轮对轴向切片投影法，准确找到轮轨多点接触。引入弹性压缩量，找到接触斑，利用一种精确计算轮...轮轨接触应力对轮轨磨耗和滚动接触疲劳影响较大，因此精确计算轮轨接触点与接触应力非常重要。本文基于重载铁路轮轨标准型面，利用改进的轮对轴向切片投影法，准确找到轮轨多点接触。引入弹性压缩量，找到接触斑，利用一种精确计算轮轨接触应力的方法求得轮轨法向接触应力，并考虑轮轨摇头角和侧滚角的影响。结果表明：该方法在寻找轮轨多点接触与计算轮轨接触应力时结果较为准确、直接和全面；轮轨接触斑随着轮对横移和摇头角变化，呈现非椭圆形状；一侧车轮轮缘和轨距角处接触，曲率半径较小，轮轨法向接触应力最大值可达3400 M Pa ，而另一侧轮轨的法向接触应力均小于2000 M Pa。在轮对横移量为0～3 mm时，摇头角的增加使右轮轨接触斑面积减小，相应的接触应力增大；在轮对横移量为4～9 mm时，摇头角的增加使右轮轨接触斑面积增大，相应的接触应力减小；摇头角的增加对左轮轨接触状态有利，但影响不明显。展开更多
In this paper, we present a new concept of the mechanical design of a humanoid robot. The goal is to build a humanoid robot utilizing a new structure which is more suitable for human-like walking with the characterist...In this paper, we present a new concept of the mechanical design of a humanoid robot. The goal is to build a humanoid robot utilizing a new structure which is more suitable for human-like walking with the characteristics of the knee stretch, heel-contact, and toe-off. Inspired by human skeleton, we made an anthropomorphic pelvis for the humanoid robot. In comparison with con- ventional humanoid robots, with such the anthropomorphic pelvis, our robot is capable of adjusting the center of gravity of the upper body by the motion of pelvic tilt, thus reducing the required torque at the ankle joint and the velocity variations in hu- man-like walking. With more precise analysis of the foot mechanism, the fixed-length inverted pendulum can be used to describe the dynamics of biped walking, thus preventing redundant works and power consumption in length variable inverted pendulum system. As the result of the new structure we propose, a humanoid robot is able to walk with human-like gait.展开更多
文摘轮轨接触应力对轮轨磨耗和滚动接触疲劳影响较大，因此精确计算轮轨接触点与接触应力非常重要。本文基于重载铁路轮轨标准型面，利用改进的轮对轴向切片投影法，准确找到轮轨多点接触。引入弹性压缩量，找到接触斑，利用一种精确计算轮轨接触应力的方法求得轮轨法向接触应力，并考虑轮轨摇头角和侧滚角的影响。结果表明：该方法在寻找轮轨多点接触与计算轮轨接触应力时结果较为准确、直接和全面；轮轨接触斑随着轮对横移和摇头角变化，呈现非椭圆形状；一侧车轮轮缘和轨距角处接触，曲率半径较小，轮轨法向接触应力最大值可达3400 M Pa ，而另一侧轮轨的法向接触应力均小于2000 M Pa。在轮对横移量为0～3 mm时，摇头角的增加使右轮轨接触斑面积减小，相应的接触应力增大；在轮对横移量为4～9 mm时，摇头角的增加使右轮轨接触斑面积增大，相应的接触应力减小；摇头角的增加对左轮轨接触状态有利，但影响不明显。
文摘In this paper, we present a new concept of the mechanical design of a humanoid robot. The goal is to build a humanoid robot utilizing a new structure which is more suitable for human-like walking with the characteristics of the knee stretch, heel-contact, and toe-off. Inspired by human skeleton, we made an anthropomorphic pelvis for the humanoid robot. In comparison with con- ventional humanoid robots, with such the anthropomorphic pelvis, our robot is capable of adjusting the center of gravity of the upper body by the motion of pelvic tilt, thus reducing the required torque at the ankle joint and the velocity variations in hu- man-like walking. With more precise analysis of the foot mechanism, the fixed-length inverted pendulum can be used to describe the dynamics of biped walking, thus preventing redundant works and power consumption in length variable inverted pendulum system. As the result of the new structure we propose, a humanoid robot is able to walk with human-like gait.
