踝后足四关节在人体步态中的运动非常精细复杂。目前足踝辅具基本都是背伸和跖屈的被动活动，不能实现运动精确伺服，更不能与健侧匹配。不符合人体生物力学特性的仿生容易导致疲劳和疼痛。我们前期优化了步态仿真技术及动态图像匹配技术，发现踝后足四关节在步态过程中存在空间运动偶联，是维持足踝部运动功能的最重要结构，是高精度仿生的关键。本项目基于前期优化的小关节运动与生物力学检测技术，获取不同工况步态环境下踝后足四关节每个骨块、每根肌腱的时间、空间和受力偶联数据及关节阻尼系数变化，将踝后足四关节各关节运动轴进行简化归并；将足踝部9组肌腱力矢量化，简化归并至3个矢量方向，建立能够实现六自由度步态仿真的足踝仿生模型；基于该优化模型改进目前足踝智能辅具并验证其生物力学有效性。研究内容可以丰富踝后足四关节及肌腱力的偶联数据，为足踝手术关节融合取舍、肌腱转位等提供优化方案，为具有简便性的高精度智能辅具仿生提供可能。

The function of ankle hindfoot joints is exquisite and complicated during the human gait cycle. Currently, the foot and ankle intelligent assistive devices mainly control the dorsi/plantar flexion movement and still not bionic enough since they can't fit for the unaffected limb and achieve accurate motion servo. Therefore, pain and fatigue are commonly seen in the users. Through the previous work, we have improve the gait simulation technique and the dynamic image matching technique, and have found the spatial motion coupling mechanism of ankle hindfoot joints during gait. We found the ankle hindfoot joints are the most important structure serve for the kinematic function of foot and ankle and are the essential part to achieve high-precision bionic ankle. Based on these high-precision biomechanical techniques, the present project aiming to obtain the time-space force coupling data of the ankle hindfoot joints and surrounding tendons under different walking conditions as well as the joint damping coefficients of each joint. We will illustrate the correspondence between the kinematic mechanism and the kinetic mechanism of the ankle hindfoot joints. The nine groups of tendon forces around the ankle will be vectorized, and further be simplified to three vector directions. Based on these researches, we can create the optimized bionic model of foot and ankle which can also simulated human gait in six degree of freedom. Based on the optimized bionic model, we will modified the current ankle intelligent assistive device prototype, and verified its biomechanical validity. The researches of current project can further add coupling data of ankle hindfoot joints kinematics and tendon forces and provide clinical guidance to the surgery of ankle and hindfoot fusion as well as the tendon transfer. The establishment of optimized bionic model is the crucial basis for the high-precision bionic designs in future assistive devices of the foot and ankle.