Further to last weeks post, I had to overcome a number of small hurdles with the Lock Box. The biggest challenge was having not programmed for quite some time. The last project of mine that required coding was for a “reverse geo-chache box”. The idea was simple, bring a locked box (there's a pattern forming here) to a location and the lock will release. The display on the box would show the distance to the location and it was up to the user to triangulate the destination. Something about carrying around a box of wires with a big red button on it through a large city put me off that type of project for a while.
Anyway, my first version of the code was far too inefficient to use. It worked and would never be seen by anyone, but the amount of repeated functions was too much to bear. The current release version on the other hand is much cleaner. It's still not the most efficient, but it is much easier to read and work with.
I did make a few mistakes along the way which should have been obvious in hind sight. The FET used to switch on the lock solenoid didn't have a suitably high current rating and blew after a few uses. Similarly, the two vibration motors are just too strong for the application. On a hard surface, the Lock Box has a tendency of slowly trying to slide itself off the edge if given half the chance.
All that being said, the project delivers on what I set out to do with it, and it's always fun to manipulate mechanisms through unconventional electronic means.
One final thought; if I were to make an updated version of the Lock Box, a larger display would be a must. You can hardly tell when the dinky padlocks are open on the current one.