According to the United States Census Bureau, the median asking price for a house has more than doubled over the past two decades. The home ownership rate in the US hit a 25 year low in 2016 at 62.9 percent. It is currently 65.6 percent, which means there are a lot of us currently living in apartments. There are many headaches that come along with apartment dwelling, but the worst is a noisy upstairs neighbor. It often feels like you're living below a professional tap dancer who practices their craft in the middle of the night. Redditor MealsWheeled built TallyWhacker to get back at their own loud upstairs neighbor.
The TallyWhacker is a smart IoT device has one function: to make as much noise as possible by banging on the ceiling. MealsWheeled can activate it with a voice command whenever the person living above them starts their basketball dribbling exercises. After receiving the command, it uses a servo arm to flick a doorstop-style spring. The unit sits attached to the ceiling, so the spring vibrating back and forth produces vibrations that resonate nicely through the neighbor's floor as noise. It is also a strange enough noise that it isn't immediately identifiable, so MealsWheeled should be able to use the project quite a lot before the neighbor catches on and retaliates.
A Google Home listens for MealsWheeled's voice command. It connects to Home Assistant, which publishes an MQTT (Message Queuing Telemetry Transport) message that an ESP8266 development board watches for. If the ESP8266 sees the MQTT message, it will use a 20kg RC servo motor to whack the doorstop spring. MealsWheeled programmed it to strike the spring at random for between 5 and 30 seconds. Power comes from an RC LiPo battery pack. A custom-designed 3D-printed mount keeps the TallyWhacker firmly secured to the ceiling.
This is an undeniably petty project and it will lead to escalation between MealsWheeled and their neighbor. But those of who live in apartments can relate to this pettiness.