David Aguilar's mission to help others after building his own prosthetic arm from LEGO
There’s no denying that David Aguilar is an inspiration, and quite frankly, a genius.
The Andorran inventor was born with Poland syndrome, a congenital disease that stopped his right forearm from fully developing.
At the age of nine, his engineering skills were already strong enough that he built himself a prosthetic arm with the LEGO® bricks he found in his toy box.
Named MK I (Mark I) – a nod to the suit worn by Iron Man – the prosthesis was revolutionary, but not totally fit for daily use.
By 18, he had improved on his design enough to create the first functional LEGO prosthetic arm and become a record breaker.
Now aged 26 and up to MK V, David – aka “Hand Solo” – has built LEGO arms for others, given a talk at NASA, and even written a book and created a videogame alongside his supportive dad Ferran.
Let’s take a look at David’s extraordinary life so far…
It was 2017 when David claimed his first world record.
That prosthesis was purely mechanical and featured a moveable elbow joint and a grabber for picking things up, which worked by David bending the elbow.
Eventually, his design evolved to be fully motorized and have five fingers that he can control through subtle movements of his arm.
And he hasn’t just worked on his own prosthesis.
In 2021, and then a bioengineering student, David created the first functional foot-controlled LEGO prosthetic arm, also the first functional LEGO prosthetic arm with a stylus, for eight-year-old Beknur Zhanibekuly (Kazakhstan), who was born with undeveloped arms.
The arm featured a grappling pincer which was controlled by a cord connected to one foot.
In the heartwarming video above, David is seen presenting a very excited Beknur with his prosthetic.
David broke these records with the help of his dad, who had built custom prosthetics to help his son ride a bike, swim and ride an electric scooter without receiving negative attention from his peers.
Beknur with his LEGO arm
For Beknur, they built a LEGO prosthetic with a pen tip – the “eMK-Beknur” – so he could use his tablet with ease.
Read about more amazing record breakers like David in our Human Body section.
Explaining how he even got into making prosthetics from LEGO in the first place, David said at the time: “Four years ago, I was lying in my bed and I was pretty bored so I took a look at my room and I saw this LEGO helicopter that was lying on my desk and decided to dismantle it.
“Every single brick was used to make my first prosthetic out of LEGO Technic.”
David as a child
When it came to MK V, David did the original design on a computer before ordering the pieces he needed, rather than using an existing set.
LEGO donated the pieces to him and even invited him to their headquarters in Billund, Denmark, for a week to participate in the development of the SPIKE Prime sets.
David was later invited to Mexico for the global launch of those sets and was also asked to be the face of a campaign called #rebuildtheworld.
His inspirational work also saw him invited to NASA in 2019. He attended the US space agency’s Cross-Industry Innovation Summit to present MK V to staff.
David and his dad are also passionate anti-bullying advocates, so much so that they’ve built a videogame called Bullying Pursuit with the help of Daniel Sánchez Mateo from Dojo System.
The game is a fun tool designed to help children, teenagers and families learn about how to deal with bullying and how to show more empathy to others.
It’ll be available as a mobile and PC game in November, on PlayStation and other consoles early next year and as a physical board game soon.
Speaking previously about his experiences growing up, David told us: “When I was young, I suffered from bullying from some of my classmates, and I can say it was pretty hard being the different one.”
Ferran added: “His mother, Nathalie, and I spent years enduring the pain of watching our son suffer from school bullying, mockery, and insults. Driven by a commitment to fight this scourge, we have reimagined the ancient game known as Ludo, or Pachisi in some countries.
“In the original game, people have to harass their opponent along the path to the finish line, knocking them out and sending them back to the start, and to be rewarded for doing so.
“To counter this negative competitiveness, I transformed the rules to foster positive collaboration by introducing a fifth player driven by chance: the ‘Bullying Monster’. We replaced negative competition with positive collaboration and fun rules for defeating the four monsters that emerge from each player's starting squares.
“Once the monsters are eliminated, a second phase begins - positive competition to reach the centre, without the need to destroy one another. This game is a joint project between father and son - a continuation of a lifelong partnership.”
The duo’s dream is to launch a school-based competition to promote their anti-bullying message further.
David and Ferran have also penned a book together, Piece by Piece: How I Built My Life (No Instructions Required).
It’s described as a heartfelt and funny memoir about David’s journey with LEGO prosthetics and is available to buy on Amazon.
It’s already been translated into seven different languages and has even sparked some interest in a film adaptation.
David and Ferran have also been busy launching their own leisure and entertainment business in Andorra called PEW-PEW, in partnership with Ferran’s best friend, Ferran Jerez, who is like an uncle to David.
The company hosts birthday parties, corporate events and groups of families and friends, with ambassador David playing an essential role in their key message of inclusiveness.
Visitors can play a unique laser tag game created by the father and son. It’s set in a post-apocalyptic Andorra where aliens are invading and players need to defend their territory.
David’s nickname Hand Solo is both a nod to Star Wars character Han Solo and his homeland of Andorra.
Find out more about him on his website or follow him on Instagram.