The work aims to design an accessible intelligent wheelchair product for individuals with mobility impairments under the vision of co-design. The research employed a macroscopic approach using the Functional Basis of Design (FBS) model to establish a research framework mapping user behaviors and functional needs to the product structure. Additionally, the Analytic Hierarchy Process (AHP) theory was utilized to identify the optimal solution for user needs and product functional elements, so as to reveal specific pain points in the design of accessible wheelchairs for a particular demographic. Finally, by inputting these design challenges into an AI large model, iterative design and optimization were conducted until the optimal design solution was achieved. Through AHP hierarchical analysis of user group need indicators, it is determined that users prioritize safety and comfort in wheelchair design. This fundamentally defines user latent behavioral characteristics and functional needs for accessible wheelchair design, subsequently establishing the overall product structure and functionality of the accessible wheelchair.