Announcing the eXperimental Robot Project


This is the blog of the eXperimental Robot Project, a project that attempts to build an open hardware humanoid robot - or, more precisely, a bipedal walking machine.

We are two robot enthusiasts from Cologne, Germany. For some years, we have been dreaming about building our own humanoid robot. However, finding plans for one has proved to be rather hard. The most impressive robot projects are very secretive, often not publishing anything beyond videos of their robots in action. University projects are more open; one can often find detailed descriptions of the mechanical construction or the control algorithms (e.g. Lola or TUlip). Still, it is very rare to find source code or CAD files, much less under an open license. The only open-hardware humanoid that we know about is the iCub, but that robot does not seem to be able to walk.

Another issue is cost. The iCub robot costs 250,000€ to build. Rumour has it that Asimo costs 150,000$ to lease for one month (reliable numbers seem hard to come by). Generally, many robots seem to be built in such a way that the cost for components alone is far beyond our budget.

This blog will document our efforts to make our dream come true. We will attempt to bring down the cost by about two orders of magnitude, to design a robot that can be built for a few thousand Euros. All hard- and software will be available under an open license for everyone to study, copy and improve. In addition, we will openly publish our ideas, findings, but also our failures.

The project has been brewing for some time now. We started by studying the problem of walking in simulation - details will follow in future blog posts. Such simulations can give us an idea about the requirements for our hardware, but, of course, they always happen in an idealized world. At some point, only trail and error in the real world will tell us what works and what does not.

Thus, we needed to set up a lab. In summer 2013, Dingfabrik, the local hackerspace where we are located, moved into a new location. As always, moving is a lot of work, and it kept all members busy for several months. In the end, however, it was worth it: we now have a lot of space, including a room dedicated to our robot project, and a reasonably complete electronics and mechanics workshop.

We decided to start with a less ambitious project, a so-called Acrobot (see next blog post). At this time, construction drawings and the control concept are mostly finished, so actual construction can start.

While our project is still rather young, we have decided that now is a good time to making it public - in the spirit of "release early, release often". We hope that others may find it interesting, contribute ideas or code, or even join the project. If you are interested, please get in touch.

That's it with the introduction - in the next blog posts, we will start talking about technical details. Welcome abord an exciting journey!