With the iterative upgrading of intelligent interaction technology, the traditional way of opening car tailgates has become difficult to meet users' dual demands for convenience and a sense of technology. To achieve a contactless intelligent operation experience, this study innovatively integrates augmented reality (AR) light and shadow technology deeply into the automotive tailgate control system, and develops an automatic electric tailgate solution based on AR light and shadow recognition. This system is equipped with a high-precision motion capture and projection interaction module, which can accurately identify the user's stepping action instructions. When the user's feet enter the preset projection area, the system will immediately trigger the automatic opening function of the tailgate, completely freeing the user from the constraints of manual operation and providing a highly futuristic intelligent interaction experience.