Abstract: To improve the accuracy and fitness of rapidly customized orthosis, a customized design and evaluation model of hallux valgus orthosis was established based on digital foot model, and the specific methods and processes were formulated as well. Together with the interview, the ergonomic user needs three-dimensional classification was utilized to get the initial user needs of hallux valgus patients, and the Analytic Hierarchy Process was applied to identify the priority of user needs. The TRIZ Conflict Resolution Principles were used for generating the innovative design direction of orthosis. The point cloud model of foot was obtained by 3D scanning, and then the three-stage data processing and deviation analysis were performed to ensure the accuracy of digital foot model. In combination with the innovative design directions, the basic model of the hallux valgus orthosis based on digital foot model were applied to generate the orthosis design alternative. The average deviation and standard deviation are used for acquiring the Orthosis Fit Index. The accuracy of the final design alternative was evaluated by the Orthosis Fit Index and the visual evaluation of the design alternative. Finally, a case of the customized design of hallux valgus orthosis is conducted to demonstrate the feasibility of the model and the specific methods and processes.

Key words: digital foot model, hallux valgus, orthosis, customized design, fit index