Repair of broken Nao robot battery pack

The battery pack for our Aldebaran / SoftBank Robotics Nao V6 robot broke and we are currently not able to find a reseller that ships to our country. Even contacting SoftBank Robotics directly did not result in any response. The official specifications are available here. Since the battery pack was clearly broken we decided to open it up to be able to find a replacement battery ourselves.

Opening the casing is difficult, since it is not only kept in place with latches, but is also glued together. We used a soldering iron at the seams to open open the case.

The battery back seems to consist of six Sony US18650NC1 2900mAh batteries. They are connected with seven wires to a PCB board. The power supply connects with two cables to the PCB board. In addition, the case has two contacts next the charger plug that could be used for detecting if the battery cover is closed. Five contacts connect the battery pack to the robot of which the first two bigger ones seem to carry the power. The four smaller contacts are probably to communicate with between the robot and the battery PCB board.

We ordered some new batteries and will keep you updated on the developments.

LEGO Resin Casting Brick in a Brick

This video will show you how to create your own LEGO bricks that enclose other LEGO bricks. I used the polyester resin pouring method to create the brick by utilising a silicon based mould. These step by step instructions help you to create your own LEGO brick. This is an ideal present for all your AFOL friends.

Here are some more photos of the models I made:

Raspberry C64 Pi Audio and Cooling Update

It was time to improve the performance of this Raspberry C64 Pi computer by adding the official regulated fan to the case. I also added a USB audio adapter to improve the sound quality. With these two inexpensive upgrades, the Raspberry Pi performs much better and the audio quality is much improved.

Invited Talk At The HumanTech Meetings

I will be giving an invited talk at the HumanTech Meetings on December 2nd. This event will be in English with Polish live translations. You can join the meeting for free. The title of my talk will be “Same same but different”. Here is the abstract:

The idea of robots have inspired humans for generations. The Bank of Asia, for example, had commissioned a building that looks like robot to host its headquarters in Bangkok. This profound interest in creating artificial entities is a blessing and a curse for the study of human-robot interaction. On the one hand it almost guarantees a headline in newspapers, but on the other hand it biases all participants in the study. Still, almost all robots that made it out of the research labs and into the market failed. This talk with try to shine some light on why robots are so (un)popular.


Not so long ago, robots were the subject of sci-fi movies or production lines in some industries. Nowadays, the use of robots in hospitals, hotels or coffee shops has been gradually increasing. All over the world, cases of robot-related anxiety have been noted. Specialists even talk about robophobia – a strong fear of robots.

During the upcoming event in the HumanTech Meetings series, organized by SWPS University’s HumanTech Center for Social and Technological Innovation, two world-renowned scientists, Professor Christoph Bartneck, University of Canterbury, New Zeland, and Professor Agnieszka Wykowska, the Italian Institute of Technology, in Genoa, Italy, will tell us about their own experience of building difficult relations with robots. The meeting will be hosted by Dr. Konrad Maj.