29
Dec
2017

Victory in the Robotex Competition Came from Thinking Outside of the Box

A bad result in Robotex last year does not mean that you should give up and not try again. We wrote previously about how the Italian team beat the other LEGO line-ups by a long way, using the old style, but faster LEGO robot. Now the Saku team, supported by Uptime, used their own weapon – old-school LEGO – and won the battle.

Let’s remember that last year the Italians won the race in 6-7 seconds with results that were far better than the others. The Italians took a slightly different approach, and instead used LEGO’s first RCX kit, which was nearly 20-year-old, but had a significant advantage thanks to its more powerful engine.

Toomas Jõgi, a supervisor of the Saku team, talks about how the preparations for this year’s Robotex went and how they learned from last year’s lessons: “The older version of the LEGO robot was, of course, found on the Internet. The choice of robots to buy was surprisingly wide. The components we used were mostly bought from a Slovenian guy who did not need them anymore. Although everyone saw last year, what success this approach brought to the Italians, nobody apart from the Saku Hobby Center team followed their example this year.”

Three Italian teams also competed with older LEGO, as in the previous year.

“We assumed that after the victory of the Italians in 2016, quite a lot of old sets would come out to battle in Robotex,” commented Toomas Jõgi, “we have even shown our kit in a few smaller local competitions in the spring, but no one has taken it as an example.”

What brought the victory?

Saku team members Jan Hendrik Jõgi (12), Karl-Johan Paste (17) and supervisor Toomas Jõgi have no clue what exactly ensured their success. “There are some hypotheses, but we won’t comment on them ourselves ;)”. The supervisor remains mysterious, “but it is clear that at such a speed, 10 mm in size or 10 grams in mass has a great significance.”

Old LEGO is much harder to code than new EV3 and NXT devices, where many things are already done, you have only to adapt them. Also, the old sensors are not so precise and high quality, giving more false information and noise. This meant that creating the software was more difficult, and the code had to work hard to distinguish the correct data from the false information.

Good line tracking software is much more difficult to write than, for example, good Sumo robot software, because it needs to be strong in mathematics. “During this process, a 6th grade schoolboy was forced to learn which is an integral and a derivative,” adds Toomas Jõgi.

The result: a 15% better time!

The Saku Hobby Center team won the Lego RCX line with a time 15% faster than the Italians, who remained in second place. The winning time was 6.79 seconds, with the second placed team coming in at 8.04 seconds.

Last year, Italian teams took all three first places, with almost twice as fast times than the Saku team which finished in fourth place.

If most competitors used the latest LEGO robot technology – the NXT that arrived in the past decade or the EV3 set started from 2013, then Italian teams had old generation (1990s) technology, now used by the Saku team, too. “We moved to LEGO’s first RCX robotic platform from 1998, and also used the Hitachi H8 / 300 8-bit microcontroller and 32 kB of memory to complete it,” supervisor Toomas Jõgi said, disclosing some technical details. “This older technology with its lightweight “brain”, with smaller engines and sensors gives you an obvious advantage in the run-up – you can build a much lighter robot with significantly higher end speed and significantly lower inertia curves.”

In a surprising devevlopment, the organizers of the competition last night decided that old and new LEGO would compete in different classes. So, two first places were announced.

“Next year, we plan to take part in the usual Robotex line-up (which is not LEGO robots),” says Toomas Jõgi.

The Competition goes into the Guinness Book of Records

More than 25,000 visitors visited Robotex in November. 3195 robot enthusiasts participated in the competition. On Sunday afternoon,  Minister of Education and Science Mailis Reps and EV100 representative Jaanus Rohumaa announced the number of robots involved – 1332, which will allow Robotex to apply for the Guinness record, becoming the world’s largest robotic event.