Nien's ITP Blog

I’ve tried everything to get my dog to stop barking excessively, but nothing seems to work. I then decided to try using some sensor tech to solve the problem. The device you see strapped to my dog’s neck is an anti-bark collar. When she barks, a sensor detects the sound and releases a citronella spray that is “supposed” to train her not to bark. However, my dog seems to be immune from the spray, which is bad news for my neighbors and my nerves.

As an exercise to get acquainted with the Arduino micro-controller, I created an apparatus that lets a person use their fingers to send digital signals to the Arduino by tapping on a metal plate. Metal contacts attached to the fingers (index, middle, ring) when touched with a metal plate will light the corresponding LED. When all 3 fingers close the switch, the larger LED turns on. This concept can be extended further by using the finger switches to open a combination lock. The correct finger combination must be pressed down in the correct sequence in order to open the lock. One of 3 small LEDs will light when a finger combination is correct. The larger LED will light once all 3 combinations are entered in the proper sequence.
 

Sensors are all around us, helping in ways and places we least expect. Here, a motion sensor provides a more sanitary way to flush the toilet in public restrooms. The way these sensors work is that a person first “arms” the sensor when they are in front of the toilet or urinal. Only when the person is done and walks away does the toilet actually flush. A cleaver 20th century add-on to something very very old.