In this project, we have to build an electro-mechanical device, based on a latch and a servo motor to lock/unlock the pet door. Moreover, we need to build a simple electronic circuit to read sensors.
Required materials and electronics components
To build the locker you need little hardware that will be available at your local hardware store:
- A small door latch, which is best if flat and without any notch. Since it has to be operated by a servo motor it has to slide very smoothly.
- Some nuts and bolts to mount the latch to the door.
- A few centimeters of metal wire (diameter of 2 mm or so).
Other required components are:
- Mini servo motor powered at 5V.
- Normally closed magnetic switch and a small magnet.
- A photoresistor.
- Resistors: 2 × 10K, 1 × 4.7K. ...