UPDATE 11 p.m. ET: MegaBots has just uploaded video of the fight to YouTube. We won’t spoil it for you. Watch to find out who won:
In 2015, two American engineers, Gui Cavalcanti and Matt Oehrlein, set out to build a giant human-piloted combat robot called Mk. II MegaBot, which could drive on tank tracks and fire 3-pound projectiles. The robot was pretty cool, they thought, but who would they fight? They decided to challenge the only other giant piloted robot in the world to a duel. That robot was a 4.5-metric-ton mech known as Kuratas and built by Suidobashi Heavy Industry, in Japan. The Japanese accepted the challenge. The fight was on.
The U.S. and Japan teams have since spent two years fortifying and weaponizing their robots, and now the duel will finally happen. Well, technically, it’s already happened: It appears that showing the fight live wasn’t feasible (there would be too much downtime for repairs and resets), so over the course of several days the robots battled each other at an undisclosed location in Japan, with cameras rolling to capture all the action.
Is this the start of a giant robot fighting league of the future? That’s the plan, according to Cavalcanti and Oehrlein, who founded MegaBots in Hayward, Calif. They recently said they’ve already started working on their next robot, and there are discussions about forming an official league.
We spoke with Cavalcanti about their new robot (a 5-meter-tall, 430-horsepower robot named Eagle Prime), how they control it, and what lessons they have to share with other robot makers.
Gui Cavalcanti: This fight is for real. We’ve spent the past year and a half building Eagle Prime to be genuinely capable of getting into a giant robot fistfight while keeping us safe. We showed our old robot shooting us in Eagle Prime with a 3-pound paint cannonball at 120 miles per hour in our debut video, we ripped the face of our old robot off, and we actually collected a ton of data from early tests on the kinds of impacts we could expect. You’ll see some terrifying, real damage to all the robots involved on Tuesday.
Spectrum: So was there a chance you could, like, die?
Cavalcanti: There definitely was a chance for injury, even with all our precautions. Ultimately, just like racing, monster trucks, and all sorts of professional sports, this is not a fundamentally safe activity. But at the end of the day, we’ve been dreaming about this since we were kids, and we decided to go for it anyway! It helps that neither team was trying to murder the other pilot—we were just trying to break their robot.
The MegaBots team with Eagle Prime.Image: MegaBots
Spectrum: How do the controls work—one of you is driving the robot and the other is controlling the arms and weapons?
Cavalcanti: Our robots have a driver in back (driving via monitors, with Eagle Prime equipped with seven different monitors), and the gunner in front. The driver controls the base and legs with two joysticks, which have a few different control mappings and modes. The gunner controls the torso twist actuation and the arms. The gunner has the ability to switch modes between aiming, play back eight different animations (like punches and grabs), and enter into “task space control,” where the gunner can translate the location of the claw through space or rotate it through different orientations. If absolutely necessary, the driver can control the entire robot, but in our experience it’s way too much information to process and act on successfully.
Spectrum: What is the hardest part of piloting the robot?
Cavalcanti: The hardest part of driving the robot is just practicing enough to get good and smooth at it. The robot has 26 degrees of freedom, controlled by two people who have to work together to accomplish tasks. Even just getting your regular driver’s license requires a few years on a learner’s permit, and here we are building a gigantic robot from scratch and then trying to make it do what we want with relatively little practice.
Spectrum: What weapons does the robot have, and what’s your favorite?
Cavalcanti: The Eagle Prime robot has modular weapons systems and can mount a 40-horsepower chainsaw, a 2-foot-diameter drill auger, two multipurpose grapple arms, and a two-barrel cannon. The chainsaw is absolutely my favorite. I had no idea it could do as much damage as it does... but it’s out of this world. If we had to do it again it would’ve been longer, larger, and even more powerful.
The Kuratas robot built by Suidobashi Heavy Industry, of Japan.Image: MegaBots
Spectrum: What was your overall strategy for the fight?
Cavalcanti: Our strategy going in to the fight is to control the battlefield. Our “default” weapon is the grapple claw, which can punch, grab, and lift elements of the playing field and the other robot. It’s proven to be one of the best choices we’ve ever made. Kuratas is faster than us, and our strategy is to negate that advantage!
Spectrum:After two years working on this project, what is one big lesson you’d like to share with your fellow roboticists?
Cavalcanti: The only way this project was possible was by using as many COTS [commercial off-the-shelf] parts as possible, and by verifying each part’s functionality as it came in. As best we could, we tested each part as it arrived, made sure it worked, and tested each subsystem before it was assembled into the full system. This let us catch errors like suppliers sending us the wrong part, suppliers sending us parts that didn’t work as advertised (for example, we lost a month of controls work by debugging a firmware issue with one of our sensors), and manufacturing errors. If I had to pass on a piece of advice, it would be to assemble in small pieces and test early and often.
Erico Guizzo is the digital product manager at IEEE Spectrum. He oversees the operation, integration, and new feature development for all digital properties and platforms, including the Spectrum website, newsletters, CMS, editorial workflow systems, and analytics and AI tools. He’s the cofounder of the IEEE Robots Guide, an award-winning interactive site about robotics. An IEEE Member, he is an electrical engineer by training and has a master’s degree in science writing from MIT.