Not only is drinking water consistently difficult, many find it overwhelming to keep track of the number of sips taken throughout the day.

Measure the amount of sips you take from a water bottle to eventually reach 10!

By checking if the lid is open, the water bottle is tilted enough, and if your face is close enough, an additional light will illuminate until you achieve 10 lights. Scroll through to see how I constructed this!

For this project I utilized these components:

• Water Bottle

• Arduino Nano 33 IOT

• 10 LED Lights

• Copper Strip

• Time of Flight Distance Sensor

• Wires

I started off by testing out the accelerometer. I remember learning in class that the accelerometer that was built-in the Arduino Nano 33 IOT could measure rotation in all 3 axes, meaning that I could use the Arduino Nano 33 IOT for processing and to measure the rotation of the bottle.

Next, I tested the Time of Flight sensor using the sample code that was provided in the library. I connected an LED that would take the analog readings from the sensor and display it as a brightness from 0 to 255. This sensor will be used to detected how close the user’s face is to the bottle.

However, in order to put the sensor in the bottle, I had to drill a hole in the water bottle lid. This way, the wires could go through the hole without bending the sensor in any way.

One component that I wanted to experiment with was an OLED display. This way, other statistics could be shown on the screen other than just how many sips the user has taken. While I got the screen to function, there were some difficulties connecting the sensor and the OLED display at the same time since they’re both using I2C connections. I decided to save this idea for a later project due to time constraints.

Instead of having the entire breadboard stuck onto the water bottle, I wanted to create a more custom solution by soldering the pieces separately. I soldered the 10 LEDs to a set of pins which created a cleaner look.

With all of the new parts tested and proven to work, I created a mini prototype of the machine with just the breadboard. This model checked the distance with the sensor, verified the angle of the rotation, and listened for a HIGH input from the 3.3v which acted as the lid opening. One thing to note is how the number of lights only changes when all of the conditions are true: at the beginning of the clip above, my face wasn’t close enough to the sensor, so when I tried to tilt the accelerator, nothing changed. The use of multiple conditional statements will be explained later below in the code.

The next step was to design and build the housing. Using cardboard, I created a sleeve with a platform built in so that it could be taken off and put back on with ease. The space between the actual bottle and the platform was crucial to allow for left handed users to carry the bottle with their desired hand. It is also important to align the platform on the left side of the bottle so that the Arduino reads the correct rotation of the bottle.

This demonstrates how the Arduino will check if the lid is open. If the copper strips from the lid and the handle are in contact, it creates a closed circuit which will send a HIGH signal to the Arduino. This is used in a conditional statement.

These first lines initialize the sensor, accelerometer, and a few variables. The numLit variable is a counter integer for how many LEDs should be lit af. The next two variables are boolean variables that are directly linked to the sensor. These will be explained more when utilized below.

After setting up the LED pins as outputs and the copper strip circuit as an input, I set up the accelerometer through the Inertial Measurement Unit (IMU). Measurements would then be outputted in the Serial monitor in x, y, and z coordinates from -1 to 1. This code was created by SimpleAccelerometer LSM6DS3 Sensor.

The lines following the “//being code for sensor” are from the Continuous Sample as part of the VL53L0X library. Basically, the Time of Flight sensor detects if an object is in front of it and outputs the distance which will be shown more in detail in the loop function.

The lines of code after the “//begin waterbottle code” are the lines that I handcoded myself. I start by initializing a variable that would retrieve the current status of the copper strips. If they were touching, the variable would equal HIGH and if the strips weren’t touching, the variable would equal LOW. I created another variable that was assigned to the sensor reading in millimeters. The following if statement checked if all conditions were true, and if they were, to set the bool variable isDrinking to true. The next if statement would increase the numLit variable by one and illuminate the corresponding number of LEDs using a for loop. Another if statement is nested inside which checks if there are 10 LEDs lit, and if so, to flash them individually and reset the numLit variable to 0.

The conditional statement “previousDrinking != isDrinking && isDrinking ==false” is used to ensure that the code inside the if statement is run over and over again. This makes it so that the code inside is only run once.

With all of that in place, the encouraging water bottle is done! This was a very involved project for me since I was working with two entirely new components (accelerometer and flight of time sensor). Also, this was my first time using soldering to connect components together. I am happy with the result for now, but I plan on upgrading this prototype in the future. I hope to use the OLED display and create a tamagochi-like experience by encouraging the user to keep the entity alive by taking a sip from the water bottle. Overall, a fun project for me!!