IoT ,

Voice control your coffee machine with google home via Raspberry Pi

Voice control your coffee machine with google home via Raspberry Pi

  • Last Updated on June 20, 2022
  • 7 min read

Cauldryn is a portable travel mug that boils water, brews coffee and tea, keeps hot beverages at desired drinking temperature, and defrost frozen food from a battery, without the need to plug it to a power outlet.


Fascinated by the growing trends: automation, IoT mobile application, a Cauldyrn representative contacted us a few months ago. They wanted our help to grow 3rd party integration in their battery-operated mugs so that they could receive command from an external device via a software interface.

The problem

Cauldryn only purpose is to maintain or raise temperature inside so that the content is in desired state. Therefore, it lacks any connectivity options as such to make a successful interface with a software application. As an analog device, it lacks a Software Development Kit (SDK) that could have allowed it to be controlled by external devices.

Think of it as a problem wherein you want to control your refrigerator with your iPhone. Sounds awesome but is it possible?

For a layman or an inexpert this is a notion—indecipherable, incomprehensible. However, for a DIY enthusiast, hobbyist, tinkerer, it’s an everyday challenge.

Moving from Raspberry Pi to Arduino

We knew there was no way we could interface an external digital device with an analog coffee mug without an intermediate device. We initially started with a Linux-running Raspberry Pi to work as an intermediate. Raspberry Pi is a great device but costly. So, we moved to Arduino.

An Arduino is a microcontroller motherboard. A microcontroller is a modest computer that can run one program at a time, over and over again.

A Raspberry Pi, one the other hand, is a general-purpose computer, usually with a Linux operating system, and the ability to run multiple programs. It is more complicated to use than an Arduino.

An Arduino board is best used for simple repetitive tasks: opening and closing a garage door, reading the outside temperature and reporting it to Twitter, driving a simple robot.

Read more: Create a chat app server using Node.js and

How we approached the problem?

To interface the Arduino with the coffee mug, we used propriety drivers provided by the manufacturer and Arduino toolkit. We added a Bluetooth module to Arduino so that it could exchange data with the Bluetooth on Google Home. Application of BLE ensured the Arduino consumes least power. We did the initial coding in node.js.


We employed Actions on Google develop platform to create an Actions project and Dialogflow agent. We enabled Webhook and linked the code to the Arduino. Relevant voice commands were hardwired into the Arduino ROM: Brew Coffee or tea, maintain a temperature, boil, or defrost.

The ingenious solution—internet of things (IoT)

Whenever a user tells Google Assistant on Google Home to brew a cup of coffee, it converts the information into a stream of text which is communicated to the Arduino inside a data block.


The software that runs Arduino would extract the text command from the data blocks and compares the received text stream to the hardwired info in the Arduino ROM. If a match is found, Arduino makes the coffee mug execute the task.

When user uses a variation of the voice command?

There may occur a chance when a user says, “prepare coffee for me” rather than the standard “Brew a cup of coffee”. In such cases, Google Assistant, thanks to its AI capabilities, can parse variation of text in a voice command and convert it into the standard command before processing or pushing them to the intermediate device.

That is a voice command “I would like to have a cup of black coffee” would be converted to the standard command “brew black coffee” by the AI engine of Google Assistant before pushing it to the Arduino board.

The Arduino as a result either receives the command exactly similar to the one hardwired into it for comparison or not at all.


Dialogflow helps build natural and rich conversational bot experiences

Dialogflow gave users a natural way to interact with the coffee machine by building appealing voice and chat-conversation interfaces driven by AI. In addition to Google Assistant, Dialogflow also builds natural and rich conversational bot experiences for Amazon Alexa, Facebook Messenger, and other popular platforms and devices.

It provided our developers with examples of what our users might call when interacting with the coffee mug. Dialogflow uses years of domain knowledge and natural language understanding to evaluate and comprehend a user's intent to help you reply appropriately.

Developing apps for iOS and android

Cauldryn also insisted us build mobile app to give commands to the coffee mug. As the new setup along with Arduino, now comes with Bluetooth 4.0 connectivity. We could connect the apps the same way Google Home.

We build the an intuitive UX to set a temperature, defrost, brew coffee and tea and boil something.



The same setup with a little variation in the code could be made to work with Google Home competitors in the form of Amazon Alexa on Amazon Echo and few phones and Siri on Apple Pod, iPhones, iPads, and Macs.

Technical specification

  • Node.Js
  • Heroku server
  • FireBase database

Future scope of the project

1. Agriculture

IoT will help in making right strategic choices with enabling farmers to contend with the enormous challenges they face like increasing water shortages, limited availability of lands, difficult to manage costs.

To meet the increasing consumption needs of a global population that is expected to grow by 70% by 2050, IoT will be the guiding light to reach the most successful Agriculture growth plan.


2. Fitness

To hone the manner in which fitness can be gauged constantly people have accepted wearable app development with open arms. You can keep track of various fitness statistics throughout the day using discreet, wearable devices to create a personalized workout plan for users, to help keep them on target, and to meet new fitness goals.


3. Infrastructure

Monitoring and controlling operations of urban and rural infrastructures like bridges, railway tracks, on- and offshore- wind-farms is the key application of IoT. Automation and optimization brought in by the IoT can even benefit waste management.


4. Healthcare

IoT enables Healthcare system to offer its patience personal monitoring system ranging from wearable heart and blood pressure monitors to living spaces equipped with sensors for monitoring general well-being of senior citizens & reducing cost of healthcare.

More and more end-to-end health monitoring IoT platforms are coming up for antenatal and chronic patients, helping one manage health vitals and recurring medication requirements.


5. Home automation

Public, private, industrial, institutions, and residential all type of buildings will be installed with IoT sensors to remotely handle basis mechanical, electrical and electronic controls.


These are some insights to worldwide burgeoning technology. With sky high benefits IoT has some loopholes as well like Security that is oftentimes brought up. With billions of devices being connected together, what can people do to make sure that their information stays secure?

We helped Cauldryn launch a new product

With the help of the new setup, codebase and, Cauldryn is launching a new cup that can be controlled by means of iOS and Android app. And, Yes, one can voice command it to brew coffee or tea, courtesy: Google Home


Tej Chalishazar

Tej is an experienced project manager with huge experience in mobile app development. He has worked on a lot of projects for various companies, ranging from startups to large corporations, and has successfully managed multiple projects from inception to launch. With a strong background in software development and project management methodologies, he is able to effectively communicate with cross-functional teams and stakeholders to ensure that projects are delivered successfully.

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