Smart Baby Anti-Fall Bed Guard Goal: To prevent babies from falling off the bed while sleeping or playing, reducing parents’ worries. Key Design: Detect Danger: Uses an ultrasonic sensor as the device’s "eyes" to continuously measure the baby’s distance from the edge of the bed. Automatic Protection: When the baby gets too close to the edge (e.g., less than 30 cm), the main unit instantly activates a motor to raise a LEGO-built "safety barrier," creating a protective wall for the baby.