UW-Makeathon: Fully Automated Watering System

A simple application of cooling plate to copndence water from air



General Idea:

Our project is Fully Automated Watering System (FAWS). The essential idea is to build an automatic IoT system which hydrates potted plants by condensation of water from air. A thermometric Peltier cooler and a heat sink are applied to create a temperature difference between air and the system in order to condense water, and the water will drip from cooler to soil.

Problem & Solution:

Plant keeper needs to water the plants regularly. In this process, negligence caused by forgetfulness, laziness and traveling, such like letting your beloved cactus thirst to death could happen, . Most of the plant watering system for potted plant is similar to a water tank that sprinkles on regular basis which requires customer to refill water before use. These systems are less inconvenient yet still demands routine check and refill, far from automated. Irrigation systems with sprinklers for lawn and greenhouse are in fact fully automated, but it is very difficult and costly to build one into a house or apartment. Our solution is an IoT system which condenses water from air and requires virtually no human interaction.

Fully Automated Advantage:

FAWS has a significant improvement when it comes to automation. Since it draws water directly from air, user simply needs to turn on the switch and the water will drip. No more labor needed. The power of the system will be automatically adjusted based on data of humidity of air and soil retrieved from moisture sensors, and user can either manually modify the power of FAWS by button or remotely configure it via a dynamic HTML web page. Given that, FAWS has a comparative automated advantage to other generic system on the market.

Hardware functionality:

Thermometric cooler is a semiconductor material that will create a fixed temperature difference on its two ends when voltage is applied. We use the cooler end of Thermometric cooler to lower the temperature of an aluminium heat sink and connect the heated end to a integrated water cooling which efficiently disposes the waste heat. The cooler end lowers the temperature of aluminium heat sink, causes a temperature difference between air and aluminum heat sink and thus condenses water onto the heat sink. Notice that thermometric cooler provides a fixed temperature difference between its two ends, if we can lower the temperature of heat end, the temperature of cool end would be even lower, creating a larger difference between air and heat sink and boosts the efficiency of water condensation. To achieve so, we connect an integrated water cooling system to dispose the waste heat, cool down the heat end and eventually the cool end.

Custom Circuit:

Our circuit specialist has designed two circuits: driver module and moisture sensor module. Driver module is the muscle of our system, and our team is proud of the fact that we design and build the module nearly from scratch. The driver module is responsible for controlling the fan speed, potentiometer, fan power, pump speed of watering cooling and cooling module. Moisture module retrieved humidity level of both air and soil, and the data are visualized so user can see the performance of our system. Schematic, module pictures and codes are uploaded to the attachment, please refer to those materials.


The ultimate goal of our team is to eliminate repetitive and unnecessary work by the use of automated IoT system. FAWS can save time and keep things running on its own. In the future, our civilization will become more efficient and human will be able to enjoy automated technology to its full extent. We definitely see FAWS to be a part of that future.

Custom parts and enclosures

Thermoelectric Cooler Mount

This piece is used to hold heat sink and cooler together. It is stored in a different file type but the content is essentially the same.

12Volt to 3.3 Volt Converter and Fuse-Back


12Volt to 3.3 Volt Converter and Fuse-Front

convert 12 volt from power supply to power mcu and sensor.

Driver Module-Front

Driver module is the skeleton of all the connected components.
 driver_module-front_(1)_C1WiM8YSBJRead More Information….
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