There are two options for use for this project. In the first, upon recognition of a bark, the system notifies the dog owner that the dog is barking in the vicinity of the door. The owner can then say "go ahead" and the door will unlock, allowing the dog out. Alternatively, the owner can train their dog to bark at the door and have it unlock automatically. Not all dogs are trained equally or equally trainable.
Future iterations could also be trained for any other pet that makes noise. The addition of two simple components, like a time of flight sensor on either side of the door, could also be added to track the direction of movement. This will let you know whether your pet is in or out of the house, a common question for pet owners who let their pets roam freely.
