The human foot provides numerous functions that let humans deal with various environments. Recently, study of the structure of the human foot and adjustment of an appropriate reaction force and vertical free moment during bipedal locomotion has gained attention. However, little is known about the mechanical (morphological) contribution of the foot structure to the reaction force and free moment. It is difficult to conduct a comparative experiment to investigate the contribution systematically by using conventional methods with human and cadaver foot experiments. This study focuses on the oblique transverse tarsal joint (TTJ) of the human foot, whose mechanical structure can generate appropriate free moments. We conduct comparative experiments with a rigid foot, a non-oblique joint foot (i.e. mimicking only the flexion/extension of the midfoot), and an oblique joint foot. Axial loading and walking experiments were conducted with these feet. The axial loading experiment demonstrated that the oblique foot generated free moment in the direction of internal rotation, as observed in the human foot. The walking experiment showed that the magnitude of the free moment generated with the oblique foot is significantly lower than that with the rigid foot during the stance phase. Using this constructive approach, the present study demonstrated that the oblique axis of the TTJ can mechanically generate free moments. This capacity might affect the transverse motion of bipedal walking.

人脚提供了许多功能，可以使人应对各种环境。近来，对人脚的结构以及在两足运动过程中调整适当的反作用力和垂直自由力矩的研究已引起关注。但是，关于脚结构对反作用力和自由力矩的机械（形态）影响知之甚少。很难进行比较实验，以通过常规方法与人和尸体足部实验一起系统地调查这一贡献。这项研究的重点是人脚的斜横tar关节（TTJ），其机械结构可以产生适当的自由力矩。我们使用坚硬的脚，不倾斜的联合脚（即仅模仿中足的弯曲/伸展）进行对比实验，和一个倾斜的关节脚。用这些脚进行轴向负荷和行走实验。轴向载荷实验表明，在人脚上观察到，倾斜脚在内部旋转方向上产生了自由力矩。步行实验表明，在站立阶段，斜脚产生的自由力矩的大小显着低于僵硬脚产生的自由力矩的大小。使用这种构造方法，本研究表明TTJ的斜轴可以机械地产生自由力矩。这种能力可能会影响双足步行的横向运动。如在人脚上观察到的那样。步行实验表明，在站立阶段，斜脚产生的自由力矩的大小显着低于僵硬脚产生的自由力矩的大小。使用这种构造方法，本研究表明TTJ的斜轴可以机械地产生自由力矩。这种能力可能会影响双足步行的横向运动。如在人脚上观察到的那样。步行实验表明，在站立阶段，斜脚产生的自由力矩的大小显着低于僵硬脚产生的自由力矩的大小。使用这种构造方法，本研究表明TTJ的斜轴可以机械地产生自由力矩。这种能力可能会影响双足步行的横向运动。