Rapiro – Assembly and first tests

Thanks to element14 and the Pi NoIR and Catch Santa Challenge, my daughter and I won a Rapiro kit with Raspberry Pi and Pi Camera.

In this post, I will describe my experiences in building and getting Rapiro up and running.


The kit came in a large white box, accompanied by a Raspberry Pi and Pi Camera. The box can be used later on to carry the assembled Rapiro.

IMG_3285 IMG_3290

All parts are neatly arranged in individual compartments.

Unfortunately, no instructions are provided with the kit.

After some searches on Rapiro’s Kickstarter page and website, I was able to gather different pieces of information:

Since Kickstarter rewards only started shipping about two to three week ago, there is not a lot of user feedback yet. Also, as I’m not a backer on Kickstarter, I am unable to post comments in order to ask questions etc …

I’ve read that a discussion forum will be open soon, but until then, I’m on my own.



Using the photo gallery, assembling Rapiro was easy. The photo instructions are very clear and make it very easy to compare with.


  • Labeling the servos and connecting them to the control board to set the initial position of the servo.
    IMG_3291 IMG_3300
  • Passing the servo cables through the foreseen slots to the control board.IMG_3301 IMG_3304
  • Connecting the RGB LEDs and attaching the final piece of the kit.IMG_3306 IMG_3309

The build took approximately 2 hours and did not require any soldering, only a screwdriver and some common sense.

Raspberry Pi

It’s possible to expand Rapiro’s capabilities by adding different components, such as:

  • Raspberry Pi and Pi Camera
  • Speakers
  • PSD distance sensor

These components do not come with the Rapiro Kit by default and Rapiro is able to function without them.

I installed the Raspberry Pi and Pi Camera as those were kindly provided by element14.

It’s important to prepare your SD card in advance, as once the head is closed, there is no access to the SD card slot or HDMI port.
I installed the latest Raspbian, enabled camera support, wifi and ssh, in order to be able to control Rapiro remotely.

IMG_3308 IMG_3314 IMG_3317
The Raspberry Pi and camera are installed in Rapiro’s head. The Pi is powered and connected to the Rapiro board via the GPIO pins. The Wi-Pi dongle is connected in the back of Rapiro’s head.


Arduino Sketch

The Arduino sketch for Rapiro can be modified and uploaded using the Arduino IDE and the micro USB connection.

It’s very useful to update the sketch to:

  • modify the initial position of the servos to properly align feet, arms, etc … in case they weren’t during installation
  • program new moves
  • etc …

In my case for example, both feet weren’t exactly sitting flat on the table and the waist was not propery aligned. So instead of taking everything apart to correct this, I modified the starting position of the feet’s and waist’s servos and uploaded the updated sketch.

// Fine angle adjustments (degrees)
int trim[MAXSN] = { 0,  // Head yaw
                    -5,  // Waist yaw
                    0,  // R Sholder roll
                    0,  // R Sholder pitch
                    0,  // R Hand grip
                    0,  // L Sholder roll
                    0,  // L Sholder pitch
                    0,  // L Hand grip
                    0,  // R Foot yaw
                    10,  // R Foot pitch
                    0,  // L Foot yaw
                    5}; // L Foot pitch

Commands via Pi

The Arduino sketch comes with some predefined movement sequences and positions. They can be called via the serial interface of the Pi.

I installed minicom:

pi@rapiro ~ $ sudo apt-get install minicom

I couldn’t find an actual list of sequences documented anywhere, so I derived some from the Arduino code.
To execute them, you pass the sequence’s number via the serial interface:

pi@rapiro ~ $ echo "#M6" | sudo minicom -b 57600 -o -D /dev/ttyAMA0

Thank you

Our cats do not necessarily like our new robot friend, but we love him!

Thank you again for this awesome prize, and stay tuned for more adventures with Rapiro.

© Frederick Vandenbosch, 2014-2021. Unauthorised use and/or duplication of this material without express and written permission from this blog’s author and owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Frederick Vandenbosch with appropriate and specific direction to the original content.