Tracking Daily Fluid Intake

Similar projects worth following
An electronically-enhanced water bottle that keeps track of people's fluid intake throughout the day. This technology will assist people to ensure they are adequately hydrated and avoid the health impacts of dehydration.


We all struggle to maintain adequate hydration from time to time and it's easy to lose track of fluid intake throughout the day or to know if it's sufficient, especially during the summer, when playing sports, or when engaged in training. Under-hydration can lead to a whole range of symptoms including headaches and fatigue and mean we're not functioning at peak performance. I've created a little project seeking to address this by designing and building a water bottle that will automatically keep track of fluid intake throughout the day.

Ideally, the electronically-enhanced water bottle will have the following features:

  • Automatic calibration
  • Automatic change in fluid volume detection and calculation
  • Easy to read display of fluid volume intake
  • Battery rechargeable via separate base plate or ingress-protected USB port
  • Drink and lay down detection via accelerometer feedback
  • Low profile and lightweight electronics
  • Low cost
  • Robust
  • End-user friendly


The idea is to use calibrated capacitive fluid sensing to measure changes in volume inside a water bottle by attaching flexible capacitive strips to the side of a plastic (or glass) bottle. In this way via MCU, changes in volume could be stored, summed and displayed via a small OLED, LCD or E-Paper display.

Initially my thought was to use an Atmel ATTINY85 as the MCU for the ease of programming (Arduino IDE + AVR ISP), relatively small size but still hand-solderable and the many code examples available for it. Plus the added bonus of relatively straight-forward porting of Arduino code to the ATTINY85. I'm open to considering the use of a more suitable MCU such as the ARM Cortex M0+ if anyone has better ideas.

I've designed a small test board so I can begin testing the concept and plan to construct a capacitive sensor from strips of copper and polyimide tape attached to a water bottle. At the moment I've opted to use a dedicated capacitance to digital converter (AD7150) which has built in temperature compensation and error correction features which should help to simplify the software side of the project.

  • 1 × Atmel ATSAMD21E18 32-bit Cortex M0+ 32-bit microcontroller (Adafruit Trinket M0 dev board)
  • 1 × Analog Devices AD7150 Dual channel capacitance to I2C digital converter
  • 1 × MIDAS MDE0213A122250BW E-Paper display, 122 X 250 Pixels, 2.13", I2C/SPI
  • 1 × NXP MMA8451Q 3-Axis I2C digital accelerometer
  • 1 × LiR2440 Rechargeable Li-ion coin cell, 3.7 V, 145 mAh

View all 6 components

  • Microcontroller Selection

    Nathan Stanley10/29/2019 at 00:27 0 comments

    I previously envisaged using an Atmel ATTINY85 8-bit MCU due to the small size and really low cost, but then realized it will not have enough I/O pins and may be too underpowered to manage everything. I've now decided to use the beautiful 32-bit ATSAMD21E18 microcontroller which is available on a few different development boards and has a lot more Flash and RAM available. I will begin by using an Adafruit Trinket M0.

    Testing the Hydralift Prototype
    Testing the Hydralift Prototype

View project log

Enjoy this project?



Martin wrote 07/25/2017 at 08:14 point

Who does not feel, if he is not "adequately hydrated"? It's called "thirst".

What do you do if the bottle claims, you had drunken enough, but you are still thirsty?

  Are you sure? yes | no

Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates