Czech Technical University students design robot that plays Beethoven’s Für Elise

Photo: archive of Czech Technical University

Two Masters students from the Faculty of Electrical Engineering at the Czech Technical University in Prague have designed a robot called RHPv2. Made out of Lego pieces, it can play Ludwig van Beethoven’s famous Für Elise piano composition. I spoke to one of the authors, Matěj Štětka, who told me that the entire idea started after the famous American pay television network HBO commissioned the university to come up with a robot that would play the tune to the next season of television show Westworlds.

“We got an order from HBO to make some kind of robot to play their anthem during the spring or summer of 2020. Due to the coronavirus the project was never realised. However, at our school we decided to continue with the project and finish it for our own purposes.”

The Czech Technical University designs many robots. Why did you decide to use Lego pieces for this one?

Of course we have many different kinds of robots here. I do not want to sound harsh, but when you put a typical robot in front of most people who do not know much about engineering, they are not usually very interested. Even though it may be capable of incredible things, they are not that interested in how it works.

“However, they know what Lego is. They know that they can build small things from Lego and that their children play with it. They have an interest in Lego and a robot made out of it can amaze them.”

How many pieces of Lego is your robot made out of?

“I am not sure, because we were not counting, but I would say that between 2,000 to 3,000 pieces.”

What is it like to build a robot out of Lego, a toy which is made out of easy to put together pieces?

“There is your problem. Lego is designed to be really easy to build with. It is really nice and designed for smaller kids to play with, potentially for older kids to programm.

“However, when you design something bigger than it is supposed to be, like this piano playing robot, the lego starts collapsing and crashing, because it is not made for this kind of large stuff.”

Why did you choose Beethoven’s “Für Elise” as the tune?

“It was actually a question put to us by our mentor Martin Hlinovský, who leads the Lego projects at our faculty. Martin Šrámek and I decided to use this sound not just because he wanted us to, but because everyone knows it and, because while it sounds fast it really is not.

“The problem that robots face when playing instruments is the speed, the beats per minute, and how many notes need to be pressed at the same time while also being close to each other.

“We chose this sound because the delay between each note is quite long, but it sounds fast. It is therefore easy to test the robot on it, while the tune itself still sounds nice and clean.”

I heard that RHPv2 will have a concert in the future. When exactly will this be?

“The plan is to have a concert, but we need to still work on the speed of playing. Right now the robot can play medium speed songs, but I would like it to be able to play the Pirates of the Carribean theme, which is really fast and hard to play. The reason behind this is that it is one tone repeated all of the time. We are working on that now.

“As far as the concert is concerned it should take place at the Czech Technical University at the end of this school year, or at the start of the new semester. That means either the end of June or the end of August.”