Matthew: Tell us more about mopedix
Thomas: My software system is split into two different parts.
First of all there is the control system, which is using an Arduino to control relays and H-bridges that also can dim light. This project is still under construction and soon I’ll be adding functions such as locking via a RFID reader and activating an alarm using an accelerometer.
But the important part of the project is the interaction between the control system and the computer. The client can be used for setting your values, e.g. when you want the moped to turn on its lights according to the intensity of the ambient light. In general it sends commands via serial connection and this gives the project a wide range of ways to communicate with the Arduino used to control the moped’s lights.
At the moment I am working with the Arduino Duemilanove, which has a built-in USB-to-serial adaptor. But there is also the possibility of communicating using a cable, e.g. RS232 or simply two wires, one for incoming data and one for outgoing data, or wireless via Bluetooth [50-100m], radio frequency [2-10m], Xbee[>90m-1.6km (1 mile)] and many more. Using Bluetooth you can also change your settings using a Nokia mobile phone running PyS60 or other devices that can send commands via the serial connection to the control system.
But to be honest, the control system has not been tested on the vehicle, as I still need to transport it from my grandparents in Poland to Germany. However, I’ve tested that it works in theory.
Matthew: What prompted you to start writing software that interacts with your moped?
Thomas: I decided to start the project in the end of 2009 when I looked on the web to see if there was something similar already available. I found some discussions in forums and elsewhere but didn’t come across anything that really did what I wanted.
The most important thing that interested me was how much such a control system would cost, because prices on the market are in the most cases not very realistic. Imagine a radio frequency controlled locking system kit for your car. Such a kit can cost around 100 Euros. Now think about making such a locking system on your own using Bluetooth and your mobile phone.
Here is a short calculation what you would need:
- a bluetooth-serial module (14 Euros from China)
- an Arduino board (20 Euros)
- a 6v relay that can handle voltages of 12v (2 Euros)
- and some other typical things like a few transistors, resistors, cables, and a solder clip (5-7 Euros).
That makes a total of 41 to 43 Euros and some hours programming your Arduino and a little Python script for your Nokia S60 mobile phone.
So, can you see it can be cost effective to offer such a system.
Another thing is that I had an Arduino Duemilanove and had been developing some applications in Python for my personal use, so I had the most important things that were needed to start my project: the resources and the knowledge.
Because of the great community, lots of Arduino users, a detailed instructions for programming the Arduino and my own Python experience, I decided to give it a go.
Matthew: What sort of interface does a moped have that allows you to hook it into a computer?
Thomas: You can use mopedix in general on any vehicle you want. I aimed it at mopeds because, as an 18 year old student, I only have a moped and access to its schematics.
By reading its schematics I noticed that the heart of my moped was actually the ignition lock. The control system that I am working on is nothing more than a digitally controlled ignition lock”, which will replace the old one and provide an interface for the client application.
The system will be powered on my moped with 6 volts and newer mopeds that have 12 volts will need at least a 9V rectifier for use with the Arduino Duemilanove or a 5V rectifier for the Arduino Mini. An Arduino Mini will be great for the control system because I believe that there will be also vehicles that will have room available than in my moped.
It should be possible to use the same software and control system on a car. So, for the future I should think about a project name that isn’t specific to a category of vehicle.
Matthew: Is there any other software, proprietary or open, that does a similar job?
Thomas: Not that I know. I found, via Google, a patent that describes a control system for bicycles, but I am sure that there is no other software, neither proprietary nor open, that can be compared with mine.
In addition to that I would really like to learn from people who are familiar in working on free software and earning money for their work to show me how to earn money on my own for buying additional modules, like a bluetooth-serial-module, to improve my software and provide the end-user a wider range using the control system.
Matthew: Why did you choose Launchpad?
Thomas: I chose Launchpad because I worked on packages that are hosted in my PPAs for the Canola project (that page is a little outdated) and I have been helping to test unstable Ubuntu packages since Lucid Alpha 3.
So I was already familiar with Launchpad but the main reason for choosing Launchpad was that it gives the possibility to other people translating my client application into their languages from English.
Moreover it gives the possibility for the end-user to get in contact with the project using the “Answers” tab on the project page or report errors by using the “Bugs” tab. As well as that the user is able to follow the future of the project by the “Blueprints” tab. But I haven’t used this feature yet because I didn’t think that there were people who would be interested in my project.
The only reason I don’t use Bazaar is that I’ve only previously worked with Subversion. I hope to take some time to learn Bazaar, in the future, switch over from Subversion.
Matthew: Thanks for telling us about mopedix!