Doggy Door

This Project was submitted to Parallax by Daryl Sandberg

This customer built an electronic dog door for their three dogs using the BASIC Stamp® 2 module and a car sunroof mechanism.

The door has three modes of operation:

1) In "Normal" mode, the door opens and closes whenever the dogs get within range of the infrared sensors. There are two sensors on the inside and two on the outside. This assures safe operation because if one or more of the sensors fails, then the others will still detect a dog.

2) The "Up" mode keeps the door in the open position. This is useful when the dogs want to play with the door (this happens frequently). All of the infrared sensors are ignored.

3) The "Down" mode keeps the dogs in at night (and other creatures out). The sensors are still monitored. If one of the inside sensors detects a dog, the door beeps twice. This lets us know that one of the dogs wants to go outside.

If one of the outside sensors detects something, the door beeps three times. This indicate that either we locked one of the dogs out or something else is outside the door in the range of the sensors.

There are three buttons on the front panel that select the mode, and four LEDs that indicate the door's status. Green is for "Normal," yellow is for "Up" and red is for "Down."  There is a blue LED to indicate a failure or inconsistency in the system. The door also has several "Safeties" build in to make certain that the door doesn't close accidentally on a dog (or burn itself out when a tennis shoe is left in the path of the sliding door).

The door also has remote control so you can change modes from the living room, bedroom or family room. When the remote is pressed, the door beeps a series of tones to indicate what mode the door is going into.

The door incorporates a counter to keep track of the number of times the door is opened. This gives important information for maintenance as the motor requires new brushes at 100,000 cycles. This is about three years (the door cycles 3,000 times per month).