[TfCD] How to Make a Hydration Coaster




Introduction: [TfCD] How to Make a Hydration Coaster


The Internet of Things (IoT) consists of all web-enabled devices that collect data from their surroundings using sensors, processors and communicative hardware (Johnson, 2015). The Internet of Things (IoT) was chosen as the emerging technology to analyse and prototype to understand its suitability for concept design.


The concept of the Internet of things was applied to a Hydration Coaster. The coaster is designed to be placed on a work area and connected to a computer. A glass/bottle can be placed on the coaster. The Coaster records how much water you are drinking. If the user needs to drink more water the device alerts the user with a notification on their laptop. The device used a pressure sensor to record when a glass/bottle is placed on the coaster. Arduino Uno works as the processor which records how long the glass/bottle is on the coaster, if the bottle has been placed on the coaster for 10 minutes the code sends information to the software python which sends a programmed noise notification to the laptop which alerts the user to drink more water. An example of this project can found in the attached video.

Strengths and Weaknesses

The device has a practical application and a core target market of busy working young people who live active lifestyles. This is the same market who are purchasing fitness wearables. The code currently can only detect the period the user has not moved the bottle. The code can be changed and a more sensitive pressure sensor can be used on to detect the amount of water which the user is drinking and communicate this through email.

Alternative Technologies

Hidrate Spark is a Kickstarter Smart water bottle which can record the amount of water the user drinks and notify when to drink more. The device uses an App (IoT) which is receives information from the sensors on the bottle and from the users fitness wearable to understand drinking habits. This device has a similar objective as the hydration coaster.

Future Prospects

This coaster can be attached to any existed bottle to convert it to a smart hydration monitoring device. However, the possibilities for the IoT seems endless. Attaching sensors to monitor everyday activity is just the beginning. IoT can improve the means which we monitor our home security, understand productivity and even detect changing environmental conditions to detect for natural disasters.


Johnson, B. (2015, August 19). How the Internet of Things Works. Retrieved from http://computer.howstuffworks.com/internet-of-thi...

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Step 1: Gather the Following Materials & Tools


  • 1 x Arduino micro pro (or another Arduino or microcontroller)
  • 1 x Micro-USB to USB cable
  • 1 x Pressure Sensor
  • 2 x Cork Coasters (From IKEA)
  • 1 x resistor 10 KOhm
  • 1 x 150mmx150mm Flexible Foam Sheet ,or any flexible material (needed for the Pressure Sensor to work)
  • 3 x wire with a female head A length of wire
  • 1 x non-conductive tape
  • 1 x Duct-tape
  • 1 x Computer
  • 1 x Water Bottle


  • 1 x hot melt glue gun
  • 1 x solder iron
  • 1 x Cutter
  • 1 x scissors
  • 1 x corrugated Cardboard


Arduino IDE: https://www.arduino.cc/en/Main/Software

Python 2.7: https://www.python.org/downloads/windows/

Time and Effort:

2 - 4 Hours

Step 2: Make the Housing

Using a cutting knife. Cut the flexible foam material and cardboard to the size of the coaster. (use the coaster as stencil).

Cut a slit in the base of one coaster, this is for placing the pressure sensor in position later.

Arrange the coaster as can be seen in the last image (Do not Glue the coster). You can cut a slit at the side of the Bottom coaster for the cable connected to the laptop.

Step 3: Arranging Electronics and Testing Sensor

Cut the one end off 2 female/female wires (keep these ends for attaching to the resistor). Attach 2 female wires to the pressure sensor using a soldering iron and cable strippers. (Use different colours to note the positive and ground wires)

Wrap the exposed solder and wire in insulating tape.

Step 4: Circuit Setup

Set up the circuit as shown below using a breadboard and test to see that connection is working using the sample code and serial plotter provided by the Arduino IDE.

Step 5: Connecting and Soldering the Circuit

Once this is working, It’s time to remove the breadboard. Solder the previously cut piece of female wire to the resistor

Assemble the circuit the same as before using male to female wires (see previous schematic).
It should look similar to the image below. Test this circuit again using sample code.

Step 6: Starting Up the Code

Connect the device to the laptop using the USB Port. Open and Upload the code to Arduino IDE. You can test its workings by using the Serial Monitor, but be sure to close it before going to the next step.

Step 7: Starting Up Python

Install Python 2.7 using the provided installer, if not done yet. When installed you will be able to use the Python text edit and use Python in the command line. For now, open up the editor, it should be in the start menu called IDLE (Python GUI). When opened copy the provided code into the editor and save it. The location does not matter that much, but to make it easier later on, please save it in C:/Python27 with a chosen name, for example Hydration_Coaster.py .

When that is done open the command line (also called cmd), this is done by opening start and searching for cmd. Open it and it will look something like the provided image.

Use the following command twice:
cd ..

This will get you into the C drive location. Then use the following command: cd Python27

If python 2.7 was installed correctly you should now be in it’s folder, which is also the folder where we save the python file earlier. To start the python file and with that the notification system, please type in this command: python Hydration_Coaster.py

And all should be on its way. If you want to quit the notification system, reopen the Command Prompt window and hold the keys Ctrl and C, this will stop the system.

Note: The notification is currently set to 10 seconds for test purposes. Once the test is complete change it to 10/15min intervals for sound notification as this is a more realistic reminder as when to drink.

Step 8: Finish

Turn up your volume on your laptop. And test the device by placing a water bottle on the Coater. Wait 10 minutes and if the bottle has not been moved, then you should receive a sound notification.

Once everything is working glue the device together using a glue gun.

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    3 years ago

    This is a great idea! I usually don't remember to drink more water until I get a headache. :)