Browse Month: September 2016

RCBoat got an upgrade: ESP8266

After some time spent trying to bring my IOIO back to life, I decided to move on and to equip my RCBoat with a new controller – ESP8266. It’s a cheap wireless module which became popular very quickly and got a huge community around itself. Because of its price and size it is really easy to use it to connect any device to the Wi-Fi, and to make some cool IoT device out of it. There are also several different firmwares available for it, but maybe the most popular is nodemcu, which allows you to do programming in Lua programming language. Overall, quite pretty module to have for a couple bucks.

Taking all of that into consideration, including my curiosity for the new ESP module, it seemed like a reasonable decision to use it as a controller for my RCBoat. And so it was.


The interior of the boat had to be reorganized, a bit squeezed as ESP8266 requires 3.3V voltage regulator as well, also some mechanical improvements were made, but at the end everything fit nicely.


ESP8266 is flashed with nodemcu firmware and programmed to behave like an AP (Access Point) which allows me to connect to it using my phone. It is also programmed to receive data and control the rest of the electronics inside the boat. On the phone, I made a Joystick app, which is sending controls to the ESP8266. Both source codes for ESP8266 and the Joystick app for Android are available on my github page.

So after making a nice water sealed package and several successful tests in the bathtub, I’ve made a ride on the canal too. This time there were no connection issues, except when I pushed it quite far away. So now enjoy the video 🙂


Queue monitoring service

Like many other things in Serbia, Student Center of Novi Sad is in some ways old fashioned, and doesn’t like to change how things work. One of things is the way how students apply for the student accommodation and how they pay for it. It’s very simple: you go to the office, you wait and then you apply/pay for the accommodation. No online mess and trouble. Most of the time, waiting time is short, but as deadlines approach, waiting room becomes a bottleneck and many students have to wait, sometimes even for couple hours.

Luckily, the waiting room is equipped with a ticketing machine, so one you get the number, in theory, you can go and do other things you have to do. The problem is that while you are away, you do not know which number is processed in the office, and you can easily miss your turn.

So after some time spent thinking about how could I make things better for us, students, I decided to create queue monitoring service. It would not abolish the queue you saw in the video above, but it will give students a possibility to move away freely without missing their turn. So it led to some investigation in the beginning and system design after, and at the end to some coding ofc. On the diagram below is initial system design, all together with SMS service which was never implemented due some bureaucratic reasons.

System desing

Excluding that, everything else fit well and is working well since it was installed. Ok, maybe not always; sometimes it does happen that local computer stops working, and that service stays outdated for couple hours/days. Right now, the idea is to change ‘local computer’ on this diagram with Raspberry PI, and leave it somewhere in the dark forever alone to do its mission.


Anyway, you can download an app for Android here, or check status online here, but if you are not a student in Novi Sad, then this information might not be useful to you. The thing that might be useful to you is on my github here, and it’s a source code for the local service and Android app. Maybe you can use it and help someone else not to wait in the line for too long 😉