Pet Water Fountain Prototype With Arduino Circuit

We are a team of three college students that chose to design a pet water fountain with an automated refillable feature as a part of our ENGR 1201 class project. We named it...The HydroNest.

The HydroNest reimagines the pet water fountain. Our prototype adds a key feature that helps automate an essential part of pet care. The HydroNest senses the water level in the fountain and refills itself when needed, taking away the hassle of having to keep an eye on the water supply and refilling it when empty.

Please enjoy learning about our project! We had a blast designing it and redesigning it, learning about electrical circuits and Arduino code. Take a look at our future improvements step. With more time and money, we would have loved to polish this design up!

Tools

1. Exacto knife
2. Drill
3. Wire snips
4. Heat gun
5. Various drill bit sizes
6. Soldering Iron
7. Solder
8. Flux
9. Wires Strippers
10. Sandpaper
11. Heat shrink

Materials

1. 5W Submersible Water Pump
2. Soil Moisture Sensor
3. Motorized Ball Valve
4. Reusable Cake Container
5. Permatex Black Silicone adhesive sealant.
6. 3/8in. Brass PEX-A Barb x 1/2 in. MNPT Male Adapter
7. Binder Clips x4
8. Relay
9. Arduino
10. Breadboard Kit
11. Alligator clip leads x2
12. Power Supply
13. Computer
14. Arduino IDE (software)
15. TinkerCad

The circuitry for this project was developed in TinkerCad. I wanted to control a motorized ball valve with a water sensor using an Arduino. I pulled the components into the workspace and used the blocks to write the code. The final code was revised toward the end of the project.

I used a breadboard kit, 2 alligator leads, a power supply, an Arduino, a relay, a water level sensor, and a ball valve and wired them together.

The water sensor has a red, black, and yellow wire. Red goes to 5V, black goes to ground, and yellow goes to A5 on the Arduino.

Pin 13 goes to the relay's DC+. GND goes to the relay's DC-, and a yellow jumper wire jumps it to IN.

The power supply positive lead connects to the COM terminal on the relay. The yellow wire connects NC to the blue wire of the ball valve. The blue wire connects NO to the red wire of the ball valve. The power supply ground lead is connected to the yellow wire of the ball valve (Common). The red and blue wires of the ball valve are voltage input wires that are wired in reverse to reverse the polarity of the motor and turn the valve open and closed.

I simplified the code after I tried to use the code from TinkerCad to run the circuit. The calibration variables are valAir and valWater. You can calibrate the water sensor to trigger the output voltage by alternately submerging the sensor in water and exposing it to air. When you do so, you can read the values in the serial monitor of this program: Arduino IDE. Then you can alter the values easily in the code to calibrate the water sensor. Also, note that the output voltage is set to leave pin 13 on the Arduino and the water sensor is wired into pin A5.

The Reservoir was a two-piece system/item which was made up of the cake container lid and bottom, The Bottom of the cake pan was flipped upside down to act as the bowl, and the Top acted as the reservoir where the water was pumped. There were 2 holes cut in the reservoir 1 for the cord for the pump and the other for the piping to allow the flow of outside water from the ball valve. They were both sealed using the Permatex sealant to waterproof it.

The lid was the bowl for the water, and there were 5 holes and 1 slot cut into it, the holes for the drainage of water, and the slot for the moisture sensor.

A center hole was drilled in the lid and the water pump hose fitting was sealed in place. The rubber hose provided with the pump was attached to the pump outlet and the hose fitting. The pump was secured on the bottom of the bowl. The pump is powered by 120VAC, so the electrical cord was cut, fed through a hole in the side of the bowl, soldered, and protected with heat shrink. This eliminated the need to cut a much larger hole to feed the electrical plug through.

The ball valve was mounted higher than the reservoir bowl to allow gravity to fill the reservoir once the ball valve opens. A barbed fitting was installed on the outlet side of the valve and rubber hose was attached and routed through the side of the bowl.

1. Leakproof
2. To ensure that the bowl was sealed properly, we filled it to the brim to make sure the weight of the water would not remove the sealant.
3. First seals peeled off of the plastic because it was to smooth to allow for good grip for the sealant
4. Sanded plastic near where sealant would go to allow for good adherence
5. Filled bowl to the brim with water and confirmed that the news seals would hold
6. Electric Flow
7. Connected the fountain to power and ensured the soldering had worked and would not overheat the cord or circuit.
8. Water Level and Flow
9. Ensured water flow through fountain did not spray out of the bowl and did not overflow the catch bowl
10. Ensured that bowl did not overfill when refilling the fountain
11. Ensured that water filled the catch tray and drained back into the bowl

Given the time, budget, and opportunity we would:

1. Add UV lighting underneath the catch bowl of the fountain. This removes harmful microorganisms from the water. Thus making the water safer to drink for pets.
2. Create the bowl and catch bowl out of glazed ceramic to prevent bacterial growth and increase options for designs.
3. Create a cover for the circuit and ball valve to increase aesthetics and decrease the space taken up by the fountain system.
4. Create a cover for the moisture sensor to prevent the flow of water from the catch bowl to the sensor. This will reduce error that may occur from the catch bowl’s water disrupting the sensors reading or feeding it false information. It will also increase aesthetics, prevent damage to the sensor, and eliminate the risk of pet injury from the sensor.
5. Create holder for moisture sensor allowing for easy insertion/removal and replacement.
6. Aesthetic design to increase appeal to pet owners and attract more consumers.