People forgetting about and leaving dangerous, expensive, unsustainable appliances on like space heaters and toasters.
What it does
The smart outlet senses when a high current appliance is drawing a lot of power. After it senses this, it starts a count down timer so that the appliance is never on for more than the user specified number of minutes. If the device stays on for more than the allowed time, it disconnects power from the appliance and alerts the user by beeping. Power can be restored via a hardware button or a web UI served by an apache server. The web UI also allows remote activation/deactivation of the device with more features planned (see below). For convenience, the smart plug also does not ever switch off automatically when a low power device is plugged in (such as phone chargers) since these do not cost as much to leave plugged in and are not dangerous if left on.
How we built it
Home made hall effect current sensor which is connected to an operational amplifier and a low pass filter which is connected to an arduino clone which is connected to a DragonBoard 410c which runs an apache server.
Challenges we ran into
Very faint voltages generated by hall effect sensor, getting server back end to communicate with arduino clone, never used a dragonboard before.
Accomplishments that we're proud of
Building a home made current sensor, great team work and building a web server for the first time.
What we learned
How to build a web server, how to make a current sensor, how to use a dragonboard, how to use Debian
What's next for The Smart, Safe and Sustainable Smart plug
Add feature to set power draw threshold which triggers the timer Add extensions for certain types of appliances (temp sensor, light, smoke, ect) Add better led indicators Add a screen to show status Add feature to show status over web UI Add feature to set more parameters over web UI Remember what timer value was set after power off Make current sensor more sensitive (raise freq on low pass, increase op-amp gain, increase windings) Calculate kwh used by appliances connected