Construct & Test Prototype

Cardboard Prototype

With our solution determined, we started work on creating a prototype box, this was a scaled down version made of cardboard intended to test the laser cutter. First, we had to determine the appropriate parameters for cardboard which took some trial and error.

For our first test, we set the parameters to 80 LB Cardstock, 75% power, one pass, 800 speed. It was too fast and needed to make another pass as it did not cut all the way through.

For our second test, we set the parameters to 80 LB Cardstock, 100% power, one pass, 100 speed. It was too slow which burned too much causing a small flame which we immediately stopped and promptly put out the flame.

Our third test was our most successful, we set the material to 80 LB Cardstock, 100% power, two passes, and 750 speed. It cut through perfectly and would use these same parameters to cut out the pieces for our prototype.

Overall, cardboard proved to be a poor material for constructing our prototype as the lack of any real volume in the interior meant little to no friction for the pieces to interlock with one another. So we had to use tape to hold it together. Though we do not expect this issue once we use real wood.

Circuit Prototype

Our initial circuit prototype used these grey connectors to connect the wires from our R307 fingerprint sensor to our Arduino Uno. We realized later that these connections were losing power and giving us a poor connection between the wires.

To improve our circuit, we hardwired the wires by twisting them together to provide a more stable connection. Along with this, we clamped power from an external power supply to provide the extra voltage that was required to power our fingerprint sensor. However, we found that we connected the sensor wrong, not to mention that the exposed wires posed to risk of interference from other connections.

In the end, we stuck the ends of the sensor's wires into female ends on wires that were both male and female ended, which solved the problem of interference. Furthermore, the wires were properly color coded to prevent confusion later down the line. Additionally, we installed and powered the Bluetooth module and added a breadboard so we can power both the sensor and Bluetooth module at once and also keeps the wires in place. We also finally got the fingerprint sensor working.

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