Industry 4.0 has made manufacturingmore flexible and more robust, leading to more customer design choices. The average consumer has grown to demand customized products leading to a new manufacturing paradigm; mass personalization. In mass personalization the customer plays an active role in the design of the product, offering input on requirements and functional needs. Most research around mass personalization has focused on the production of small to one batch sizes, but because of the increased customer involvement more attention should be given to personalized design. One of the key issues with personalized design is the inability to gather accurate customer requirements. Despite this, almost none of the current mass personalization literature has tried to solve this problem. This paper will address this problem by creating a customer/product interaction digital twin. This will be one of the first works dedicated to developing a customer requirement gathering (CRG) system as well as one of the first works to do so using a digital twin as a foundation.