摘要:Because of the motion of ankle joint, the surface morphological changes. The relevant products including ankle brace, ankle boot, etc. with both important protective effect on ankle and comfort should be designed to match the ankle varies states. The samples data with 15° plantar flexion, 40° dorsiflexion and neutral position of lower limbs(N=105) were scanned. This study analyzed the feature of the ankle morphological changes and divided it into four parts: anterolateral (I), posterolateral (II), posteromedial (III) and anteromedial (IV). The anterior and posterior parts had large contraction and expansion during plantar flexion and dorsiflexion motions. The medial and lateral parts of ankle shape were asymmetric, but had equal skin areas. Therefore, the area of the entire ankle surface remained almost the same when morphological changes. We unified the data of the models and measured the distances of characteristic points. According to the main dimensions, the ankles were classified into 17 groups. The rigid brace design was taken as an example to fit mass ankles. It showed a great statistical comfort degree in total by the user experience and evaluation. The method combining with features of ankle morphological changes and shape classification was proved to be effective for the ankle related products design to fit mass ankles.