SHARPER SENSE OF DIRECTION FOR LEARNING ROBOT
Two TechPeople consultants with expertise in low-level embedded systems and Digital Signal Processing were tasked with giving the educational mini-robot from Kubo Robotics a sharper sense of place.

KUBO Robotics started as a master project for two students at the University of Southern Denmark. They wanted to do something to give children between the ages of 4 and 10 an understanding of coding and computers - what is known in the trade as Computational Thinking. The result was KUBO, an innovative programming language that uses Tag Tiles to connect coding with the physical world. Tag Tiles are plastic pieces that represent different commands with different symbols and can be combined like puzzle pieces.

The tiles teach a small two-wheeled robot to drive along a certain track. In addition to the tiles, it can also drive on a map, for example a picture of the floor of a sports hall. The Kubo robot can then be programmed to roll onto the pitch, score a goal, take a rest on the substitutes' bench and return to the pitch.  

Continuously expanded

Since its launch in 2015, KUBO has received a host of awards and is now sold almost worldwide. The system has been continuously expanded and is now available in four different versions with accompanying teacher guides, lesson plans, inspirational videos and many other accessories. 

On the technological front, the developers behind KUBO have also invested in development, including an updated version of the small, self-propelled robot. The first generation of the robot found its route by reading the system's Tag Tiles via RFID, a technology also used for contactless payment with e.g. Dankort. An RFID chip in the robot communicates with a corresponding chip in the tile, which tells the robot to go straight, right or left.

New robot with a sense of place

Educational Concept Engineer Anton Mikkonen Møllegaard-Schroll explains:

"We wanted to give the new generation robot a sharper sense of direction. The first generation ran 'blind' in the sense that it was programmed to run a certain distance per Tag Tile. The RFID technology worked similarly to a GPS, indicating a route towards a destination. When the robot read a TagTile, it knew whether to go straight or turn. It also knew how far to go per TagTile."

"We wanted the new generation robot to also be able to see exactly where it was in relation to the start point of the route. To do this, we integrated an accelerometer and a gyroscope into the robot's electronics. An accelerometer measures acceleration on three axes, while a gyroscope measures inclination on three axes. We then asked the consultants from TechPeople to clarify how to integrate the two sensors into the control of the robot's movements."

Integrated gyroscope

It turned out that it was possible to integrate data from the gyroscope in such a way that the robot could use it to adjust its route. This made it more adept at driving the specified route accurately, compared to before when it was not possible for it to detect if, for example, one of its wheels started to slip. However, the gyroscope could detect this disturbance. The robot could then adjust its course to get back on track and follow the route it had set.

Registers when lifted

On the other hand, it was not possible to integrate data from the accelerometer. The signal from the accelerometer contained so much noise that, even after extensive filtering and cleaning, it was impossible to convert the data into meaningful information that the robot could use to navigate.

However, it was possible to combine data from the gyroscope and accelerometer so that the robot can now detect when it is being lifted, for example. When this happens, the wheels automatically stop turning.

In addition, TechPeople consultants performed a partial integration of a small operating system, FreeRTOS, for possible further development at a later stage. FreeRTOS is a real-time operating system for embedded systems, which allows for automatic prioritisation of computational tasks in relation to each other and offers multitasking advantages.

On target despite tight deadline

Daniel Lindegaard, CTO at KUBO Robotics, talks about the collaboration with TechPeople:

"At KUBO we focus on our core competence, learning technology. That's why we have only a few technology-specific specialists in the company. This means that we occasionally need specialist consultants to solve some of the technical challenges we face."
"When we contacted TechPeople we were faced with an emergency. We needed to solve some technical issues in a hurry so that we were not forced to postpone the launch of generation 2 of our learning robot. TechPeople was good at quickly finding consultants who could help us finish within a tight deadline, so we could go to market with the robot on schedule."