As you will have guessed given our title, we do love hacks round right here, and this one is a superb instance of creating some frequent, on a regular basis issues work in unusual methods. [Nathan] despatched in his hack to detect the door lock place in his basement.
Having a home that dates again to the Eighteen Nineties, a lot of it was not very conducive to utilizing off-the-shelf dwelling automation units. [Nathan] needed a approach to verify the standing of the basement deadbolt. He went about placing collectively a customized sensor utilizing some spare elements, together with a spare BeagleBone Black. Going full MacGyver, [Nathan] used springs from a ballpoint pen to craft a compliant contact for his sensor.
The pair of springs sat within the door body and got here in touch with the deadbolt; given they’re springs, the precise place of the sensor was not very delicate, as if too shut it might simply compress the springs barely extra. The springs had been wired to the BeagleBone Black’s GPIO, appearing as a change to sense when there was conductivity between the springs by way of the deadbolt.
This wasn’t only a plug-it-in-and-it-works sort of undertaking, thoughts you; the BeagleBone Black was over 15 ft away from the sensors, lending loads of alternative for noise to be launched into the traces. To fight this, [Nathan] created an RC filter to filter out all of the high-frequency noise picked up by his sensor. Following the RC filter, he added in some code to deal with the debounce of the sensor, because the springs have some inherent noise in them. Thanks [Nathan] for sending in your resourceful hack; we love seeing the resourcefulness of reusing issues already available for different functions. You’ll want to try a few of the different repurposed elements we’ve featured.
