Rapiro: The Rasp Pi robot

When Shota Ishiwatari (Figure 1) began his Kickstarter campaign this past summer, he did not expect the huge success that resulted. He reached his goal of UK£ 20,000 after just two days. By the time the campaign was over, it had gathered UK£ 75,000.

Figure 1: Shota Ishiwatari, the creator of Rapiro.

In a conversation with Raspberry Pi Geek, Ishiwatari says, "I intentionally chose to make the campaign goal not too high in order to increase the probability of achieving the goal. Given the worldwide attention, the amount that I originally envisioned was surpassed by far. Even so, we will need every single pound of the amount actually achieved to finance production costs." Just what was it that made the Kickstarter participants so enthusiastic?

On the web page for the campaign [1], a picture shows the small humanoid robot performing various activities with its diverse joints and servo motors (Figure 2). Ishiwatari christened the model Rapiro, an abbreviation for Raspberry Pi Robot because the robot uses a Raspberry Pi for a brain.

Figure 2: The Rapiro shows itself to be flexible and extremely versatile.

The Innards

For muscles, the 25-centimeter small robot has 12 servo motors that are controlled by an Arduino compatible board. It has eyes that shine, thanks to colored LEDs. Theoretically, the Rapiro also functions without a built-in Raspberry Pi, but the user forfeits many capabilities in such a setup. For example, because of the minicomputer, you can not only program the humanoid in Python but also install additional hardware add-ons for the Pi.

By means of a USB microphone adapter and the open source engine Julius, you can animate your small companion with functional language comprehension as needed. Installation of a Pi camera directly into the head is made possible with a specially designed bracket. You could even add a Wi-Fi stick. With Wi-Fi, you can control the Rapiro over the Internet, or you can use the online connection so that Rapiro verbally reminds you of appointments from your Google calendar. Shota Ishiwatari will soon put up example snippets of the software code on the Rapiro project homepage [2].

The Rasp Pi in the robot's head (Figure 3) can of course make full use of all operating system capabilities via software. For example, cron jobs could be used to trigger actions at specific times of day. By using sensors, Rapiro's actions become especially interesting.

Figure 3: A Raspberry Pi makes up the "brain" of Rapiro.

Open Concept

Regarding the origins of the Rapiro project Ishiwatari explains that, "Last year I worked a lot on the subject of Raspberry Pi, and also spent considerable time looking at 3D printing. At some point I began to think about designing a robot with a printed humanoid shell." He undertook the entire development process himself, including modeling, designing, and programming. The result was intended not only to look pretty but also to be technically attractive.

Additionally, the developer had very concrete reasons for the use of each selected component. When asked why he didn't install different boards, Ishiwatari responds, "Open platforms like Arduino and Raspberry Pi connect developers across the entire world. I think that people from many different countries will be working on software and hardware extensions for the Rapiro."

There is also open source thinking behind the robot. In the future, the developer wants to put the STL (stereolithography) file for the housing on the Internet so that anybody can produce their own Rapiro with the help of a 3D printer. You would only have to procure the necessary electronic components. This information will also make it possible for each person to construct the 3D model for the robot shell according to their own wishes. You would only have to screw together the individual pieces of the housing (Figure 4) and the insides. You don't need to be an expert at soldering, so beginners can accomplish this project as well.

Figure 4: The individual parts of the Rapiro housing.

The industrial production of the Rapiro housing was financed with Kickstarter. The result should be somewhat more aesthetically pleasing than a robot that you print yourself from cheap PLA (polylactic acid). The production phase starts in December 2013. Those people who contributed at least UK£ 229 to the campaign will receive a sample robot. Everybody else has to wait until 2014. Then you will be able to purchase the little buddy for UK£ 270.

On top of this price, you will have to add taxes according to the country of purchase. For this price, the kit contains all the parts necessary to put the robot together and to start using it. The Raspberry Pi has to be purchased separately, however. In comparison, other commercially available Linux robots currently cost 10 times as much.