A more cutting-edge design is to integrate a language learning model into the skeleton, allowing American sex dolls to change the frequency of pupil contraction according to the content of the conversation, and even establish personalized interaction profiles by analyzing voiceprint characteristics. This type of upgrade not only blurs the boundaries between toys and partners, but also redefines the value positioning of full size sex dolls in the lonely economy.The "self-cleaning skin" developed by American sex doll manufacturers is covered with a titanium dioxide photocatalyst coating, which can decompose 99% of microorganisms under sunlight. A more innovative internal cleaning system uses magnetically controlled wandering robots - these micro devices autonomously navigate the internal cavities of the doll, kill pathogens with ultraviolet LED lights and collect metabolic residues.