This article presents a model for product design in an interdisciplinary way with participation of the university, private company and the user. The proposal was implemented in the design of an assistive product for mobility according to the ISO9999: 2007 standard. The structure considers the user as the central axis of the design process. In the application, the interdisciplinary team was made up of engineers, industrial designers, an occupational therapist and a psychologist. In the model, the creative phase of the design process is supported with the Theory of Inventive Problem Solving -TRIZ and the analytical phase, with an expanded model of Axiomatic Design, which involves perceptual requirements. In the design of the assistive product, four main requirements were found: the first, to move the technical system; the second, to carry the user; the third, to switch between sitting and semisitting positions; and finally, to fold the system. It is concluded that the model favors the interaction of disciplines and organizations from the moment of the conception of the problem and not in sequential stages. This contributes to an integrated view of the problem from an ergonomic, technical, aesthetic and commercial point of view. The use of the theory of inventive problem solving contributes to the systemic analysis of the problem, to the technological surveillance of the product and to the determination of the product requirements. Finally, the use of the expanded model of axiomatic design structures the design process, takes into consideration in a rational way the perceptual requirements, and facilitates the transition from the conceptual design to the manufacturing of the product. The application of the proposed model in an assistive product for mobility made it possible to conceive a technical system that gives more autonomy to the user that changes the propulsion paradigm, that favors the standing position and which does not use external sources of energy to perform different functions.