Introduction: LED Force Pressure Dog Water Bowl

This is my first instructable/electronic project I have ever done. This was a great learning experience for me. I decided to create a dog bowl that lets the owner know when the bowl is empty without having to go up to it and kick it to see if it is full or not. I wanted the bowl to be red when empty and blue when full. I also wanted it to where the bowl would transition through purples when it was becoming empty. I hope you have a lot of fun with this project and feel free to give me any suggestions because I am all about lifelong learning and making my projects the best they can be. I hope you enjoy it as much as me and my dog do.

Step 1: What You'll Need.


- Woofy friend, or one that meows will work too.

- 1 x 2 Pine 13 ft

- 6 penny Nails

- Nail gun

- Wood Putty

- JigSaw

- "Glue" (Very dangerous, use caution.) NEEDED : Mask/Closed toe shoes/ Protective eyewear/Gloves.

- 400 Square Inches Plexiglass

- Frost Spray

- White Exterior (SAMPLE will be cheaper, $5) Paint (Can get waterproof, recommended)

- Metal Dog bowl

- Washer (1)

- Electrical Tape

- Quarter- inch Plywood

- #4 wood screws (4)


- Arduino Uno Board & USB Cable

- Protective Eyewear

- Closed toe shoes

- Breadboard

- Wiring

- Force Sensor

RECOMMEND THIS INSTEAD (might work better)

- Adafruit White LED Strip

- Wire Cutters

- Wire Strippers

- Sodder

- Soldering Iron

- 110 Ohm Resistors (2), (brown, brown, black, black, brown)

- 9V Battery Clip with 5.5mm/2.1mm Plug

- 9V Battery

LED Strip Connector

Heat Shrink

Step 2: Base Structure

Cut the 1x2 Pine with the jigsaw

8 pieces (12 inches long)

4 pieces (10 inches long)

The shorter pieces go in the middle on the box.

WARNING: ( IF YOU HAVE A DOG THAT IS SHORT THESE MEASUREMENTS WILL BE WAY TOO TALL FOR YOUR FLUFFY FRIEND) I have a very tall Aussie. Also note, the water bowl will be sitting on top of this box so it with be even taller than 12 inches.

Use the 6 Penny Nails to secure everything together with the nail gun. Remember the (10 in long) pieces go in the middle.

Use a putty wood filler to cover the nail holes. Let it dry before moving on.

Make a (2) squares with the (12 in long) then put the (10 in long) connecting the squares to my a box.

Cut the piece of Quarter inch plywood to fit the top of the box. When buying the plywood, go ahead and bring the box you made and have the workers cut the top for you so you know it fits properly and also saves you the struggle of using the dangerous jigsaw again. See if they can also make an inch slit in the middle of the top so you can slide your sensor through easily.


Be careful of fingers!! We almost lost a few!

Step 3: Paint!

2. Use the White Exterior Paint to paint the whole box. This helps hide blemishes. If you want to get real fancy then use a primer. I did not and it came out great. You don't need primer with this house paint. The paint in a gallon is expensive but they sell samples that worked. I didn't even use half a sample jar. You can paint it whatever color you would like. I just thought white would look clean and the LEDs would give it the colors it deserves.

Let dry over night.

Step 4: Plexiglass

3. Cut the plexiglass to fit the inside of your frame. I had someone measure and cut this for me because I did not feel comfortable doing it myself. It is ok for someone to help out especially with power tools. It should be able to slide on in without any problems. Make sure nothing is sticking out of the top or bottom. Mark which plexiglass goes to which side.

4. Spray the Plexiglass with the nice frost spray so you do not see inside the box. You do not want to see the wiring. Spray till you feel comfortable with how it looks. Make sure to let it dry.


Put the "Glue" (Epoxy) on the inside around the edges. Slide the plexiglass inside and press them in firmly so they will hold to the sides. Do this for all four sides.


Save the glue because we will need it to glue the top on later. Let it sit overnight.

Step 5: CODE

Plug your Arduino Uno to the computer.

Download the AdaFruit Neopixel Library from the Adafruit Website:

Upload this code:


#define PIXEL_PIN 6

#define PIXEL_COUNT 8

#define SENSOR_PIN A0

float threshold = .05; float sensorValue; // Flexiforce quick start example // Reads A0 every 100ms and sends voltage value over serial Adafruit_NeoPixel strip = Adafruit_NeoPixel(PIXEL_COUNT, PIXEL_PIN, NEO_GRB + NEO_KHZ800); bool oldState = HIGH; float showType = 0;

void setup() { Serial.begin(9600); pinMode(SENSOR_PIN,INPUT); // Start serial at 9600 baud strip.begin();; // Initialize all pixels to 'off' }

void loop() { // Read the input on analog pin 0: sensorValue = analogRead(A0); // Convert the analog reading (which goes from 0 - 1023) to a voltage (0 - 5V): // float voltage = sensorValue * (5.0 / 1023.0); // Print out the value you read: Serial.println(sensorValue); delay(100); // Wait 100 milliseconds // if(sensorValue<400){ // colorWipe(strip.Color(255,0,0), 100); //magenta // } // // else if(sensorValue>=400 && sensorValue<=800){ // colorWipe(strip.Color(18,240,190), 100); //teal // } // // else{ // colorWipe(strip.Color(255,236,146), 100); // off white // } //

float r = map(sensorValue, 1,200, 0,255); float b = map(sensorValue, 1,200, 0,255);

if(sensorValue <= 0 ) { colorWipe(strip.Color(255,0,0), 10); } else if(sensorValue <= 300 ) { colorWipe(strip.Color(255-r,0,b), 10); }

else colorWipe(strip.Color(0,0,b), 10);


// Fill the dots one after the other with a color void colorWipe(uint32_t c, uint8_t wait) { for(uint16_t i=1; i

Step 6: Breadboarding

Breadboard this before soldering it to the open board. Remember the resistors are 110 ohms. Brown Brown Black Black Brown.

Step 7: More Boarding

Step 8: Installation of Parts


Use the screws to screw the board and the Arduino to plywood top. There are holes to do that. I used velcro to secure the battery to it as well. Make sure you leave enough room on the edges in order to secure the top. I put screws through the silicon of the LEDs to secure it.

Step 9: Top It Off

Put some more of the glue from earlier around the top on both sides and secure it down and let it sit overnight.

Step 10: Sensor

Pull only the round part of the sensor through the slit and peel off the backing in order to stick it to the wood. Then put a small piece of electric tape on top to keep it from interactive with the washer we are going to set on it. Put the washer in the middle of the sensor and secure it with the same size of electrical tape. This allows the sensor to work. It isolates the pressure of the bowl to one point so the sensor can read it. Plug it in and put your dog bowl on top. Fill her up and you are ready to go.

Step 11: Finished!