Get notified by ordinary coffee machine

4 min readAug 20, 2018

Do you like to drink a coffee? Would you like to get notified by coffee machine?

Story

We have a team who works in different offices and floors. And the all offices have their own coffee or tea machine. I prefer filter coffee. The operation of this kind of machines is simple. If you want to have 10 cups of coffee, you must wait in about 10 minutes. It is so boring.

I decided to notify me and my all colleagues about the progress of the coffee machine. And finally, they got a push notification message like ‘Coffee Ready’

So, how did I do this? Lets talk about my story.

Research and development

I really have a problem with the keyword ‘research’. The all-purpose of this research is making fun. So, it is not a serious thing for this development.

First of all, I could be able to create a new electronic circuit also using Arduino etc. and wire that circuit to machine nicely. The idea is simple, wire cables to a resistor and the other actuator like a water actuator. I did not like this thought because every device is different and I don’t want to harm them accidentally. That means the solution came with soldering is not reusable. So, I want to solve this challenge without touching any coffee machine.

The other thought is a choice one among us. His or her responsibility is observing device status and report all of us. Stop there, it is a bad joke :)

The last thought is a create a new device instead of a person for observing the coffee machine. Here is the simplest explanation. Every electronic device consumes electricity naturally. Devices which have a resistor like a coffee machine or other water boiling devices consume more electricity when heating the resistor. No dirty things are needed as other thoughts.

So, I decided to use this thought and I planned to measure the current of electricity in watts. The idea is simple, track power consumption and send a notification. The algorithm is simpler than the idea. If the power consumption is going down after the highest period a while, the machine completes the brewing/boiling stage. For example, if I measure a 5 amperage more than 3 minutes than it is in brewing state. And when the power consumption goes out, brewing is completed.

Choosing a true parts

After all design decisions made, I chose a current sensor. Tried to use SCT Sensors. They have a long cable and not stabilized header. That sensors are very useful in many applications but not this project. I wasted my very valuable times while stabilizing. Device with an extra wires goes out is not a thing I want.

Finally, I discovered a new sensor coded ACS712. That’s another current sensor which is easy to embed on a device without outgoing cables.

I do not want to create a nerdish content which is read-only for nerds :). So, I decided to write this store with images. If you want to have more information about electronic schematics or codes you can visit the following repository.

https://github.com/omerfarukz/coffee-ready

Development

My other challenge is about making the device simpler and smaller. I have a 3d printer and 3d modeling skills but it is not trusted way for working electricity. Decided to break my old remote controlled power plugs, and embed my device inside that. Do not forget the basic, all these pains for making fun.

Designed a wifi enabled electronic circuit using ESP8266.

Here is my prototype. It can measure the current of electricity and able to send internet.

Did you see the decreasing value on 09:56. That means the coffee machine completed its brewing task. Our coffee is ready to have.

Finally, my colleagues and I got notified by email or as a push notification like below.

Pay attention to the message, I gave an extra information about the amount of coffee (Cups: 4+). Brewing time is related to amount. If brewing takes 4 minutes, it means 4 cups of coffee is brewed.

The prototype is works perfectly.

Conclusion

I underestimated the old and stable solutions for creating a new simplest things. Do not do this.

This project needs your help. You might be want to contribute this project or make yours. Also, you might want to share this with your IT department(I like you guys). The repository link is below. Do not be hesitate for contribution.