Reachy is an open source interactive robot from Pollen Robotics that can be programmed to handle a wide variety of tasks. It uses cameras to perceive its environment. You can program it to serve drinks, cook food, and do a whole lot more. This video shows its face tracking feature.
With its face tracking app, the robot can locate people in its field of view. It uses an AI face detection module on its Edge TPU. It moves its head to follow the closest person.