Need help on my home automation project

Hey guys. I'm new to this forum, so please excuse me if I post something wrong.

I'm building a very barebones home automation device that remotely controls appliances connected to the microcontroller when sent a signal. The problem I'm facing is that I need to send those signals through an Android phone with my Arduino connected to my PC through USB. How exactly do I do that? Can I send signals to my Arduino over a terminal?

I have the Arduino Uno, just in case. And I'd prefer not to add any modules (Ethernet, WiFi) to my Arduino because they are not readily available where I live

I'd prefer not to add any modules (Ethernet, WiFi) to my Arduino because they are not readily available where I live

I won't ask how you got the Arduino in the first place, but this seems to be a pretty pointless exercise, not to mention an unnecessarily difficult one. I guess it will be possible for you to communicate via a PC but it is probably a lot simpler to send the signal direct to Arduino via Bluetooth and, if you live on planet Earth, getting a $7 bluetooth module would surely be well worth the effort..

You might find the following background notes useful

There are several Android bluetooth apps available, and probably WiFi too.

The Arduino was provided by my college. And this is kind of a project where the team that spends the least while completing the project wins, so that's why I need to know how to send commands from my phone to the Arduino over a PC.

Phone>PC>Arduino connected to PC.

Any help would be appreciated.

Well I guess the first thing to do is ensure there is an Android app that is suitable for the purpose. You may find there is a simple terminal programme that runs on USB host port but, if there isn’t one, it is down to you to write it.This also assumes your phone has a USB host connection. The same applies for a terminal PC<>phone over WiFi. This is not an Arduino problem.

The next step would then be to find a PC programme that will relay commands from one serial port to another. I don’t think it would be hard to find one or, if you can’t, it would not be hard to do it yourself in QuickBasic or the like. Again, this is not an Arduino problem.

The next thing to do is spy on the other teams and see if they think this project is stupid too, and would rather spend the money.

I would also suggest that spending the money on the bluetooth and concentrating on saving money on whatever methods you intend for the actual control of the devices might be a good idea. If you find the cost of the wire and plugs is greater than the cost of the bluetooth module, remember where you heard it first.

Thanks for the help, Nick. I’ll try out your method.

And the thing is, here in India where I live, the cost of the bluetooth module is close to $30 and that is a lot for a never to be used again component. The Arduino board costs less than that. $30 might be cheap but when you convert it to the Indian rupee, it’s a lot.

I respect what you say, I know nothing about the situation in India and obviously can’t comment - other than that I’m amazed about the $30, and would expect you to buy the module for $7 from China just like I do.

Having said that I submit that the project is stupid and utterly impractical. Further, if you are really serious about money you should consider

  1. Buy the bluetooth
  2. Use standard Android<>Arduino bluetooth apps


  1. Sell the PC.

Thereby not only finishing the job at a profit, but probably quicker than the other teams too.

Even if you don’t actually do that, you should present it as an option - a practical solution to a stupid problem. You should get extra points - and thoroughly deserve them.