This is my project from MesaHacks 2018. I competed in this hackathon solo, and I won first place along with the "best hardware hack" award. I put this prototype together in under 8 hours from scratch.
Here's how it works:
Everything starts at the water reservoir. As water accumulates, the water level is monitored by a water level sensor that reports its readings back to the Arduino Microcontroller. This is to ensure that the water pump doesn't burn itself out on a dry tank, and so that the pump can prevent the reservoir from overflowing. The water level sensor works in conjunction with a nearby humidity, temperature and light sensor, regulating the circumstances in which the water pump is allowed to run. You wouldn't want to dump ice cold water on temperature sensitive crops.
The temperature and humidity sensors can be accessed by any implementation of a crop irrigation profile (crowd sourced). The only sensor that you can't access is the light sensor (photoresistor) which is hard wired into a circuit that I designed, built and calibrated to only allow the water pump to run when the light intensity threshold is met. This is more of a hardware fail safe, in case the software experiences unexpected behavior.
The prototype comes preloaded with a sample irrigation profile. The user can select which profile to run with the built-in LCD menu system. There is an up, down and action key to navigate the menu system.
The prototype comes with a water mill attached to DC motor that generates a little bit of power, just as a proof of concept that there are no limits to the design's sustainability.