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BattleBots: Behind the Scenes With Ghost Raptor

The inside take on making dangerous robots fight for fun and glory

4 min read
A woman and four men surround a gleaming tracked robot on a push cart. They are standing in a brightly lit entrance to an  arena. The woman is wearing a black bodycon dress and the men are wearing black t-shirts all with a stylized animal skull logo
Courtesy of BattleBots/Discovery Channel

As a fashiontech designer, I spend a lot of time making sure my designs are safe, whether it's a robotic spider dress or a prosthetic leg with a built-in Tesla coil and spark gaps. So when I got invited to help update a robot designed to kill other robots in a televised death-match arena, I thought: Oki-doki, that sounds like a chance to do something different. And smash things.

I was in. Our first match airs tonight at 8 p.m. eastern, but the road to the arena began months before the contest began filming in Las Vegas last autumn. My team is Raptor, and our robot is Ghost Raptor, a veteran of many battles from earlier seasons of the BattleBots show, which is currently running on the Discovery Channel in the United States.

Captained by Chuck Pitzer, principal engineer at Fetch Robotics, and with Eric Diehr, Xo Wang, Sabri Sansoy, and myself, our team's first task was to decide how to upgrade Ghost Raptor. Every year both the rules and the arena design changes, both to keep things fresh for viewers and to discourage teams from converging on very similar optimized designs over time. We decided to add a flamethrower, in the hopes of scorching the electronics of our robot's opponents, or better yet, causing their batteries to explode. We also added a horn that could be triggered to flip up and right Ghost Raptor if it found itself on its back, which borrowed from some of my experience incorporating unicorn-horn-style designs.

The contest is held in a cluster of semipermanent tents in a parking lot behind Caesar's Palace on the Las Vegas strip. One large tent housed the arena, and another large tent was the Pit, where all the teams finish preparing—and later repairing—their robots. A corner was given over to the "Haaspital," where Haas provided CNC mills and staff alongside folks from Autodesk Fusion 360, who together made parts for teams right there in the Pit. Smaller surrounding tents were dedicated to specific functions that were separated from the Pit for safety: For example, there was a tent for welding, with rigs and experts provided by Lincoln Electric; a tent with two small test arenas; a tent that housed all the teams' lithium batteries (robots are not allowed to be energized until a battle or if they are using a test arena because of the risk of fire); and my favorite outside area, the pyrotechnic test zone. As we were incorporating a flamethrower, Ghost Raptor had to pass a safety check by BattleBots' in-house expert, the legendary "Pyro" Pete Cappadocia. Pyro Pete was beloved in the Pit because he didn't just do checks, but also gave ample advice to teams, drawing on his decades of experience of making spectacular live effects without getting anyone scorched in the process, and we learned a great deal from him.

The vibe in the Pit was very friendly, with teams frequently swapping tools and advice. Unless there's a last-minute change due to a dropout, you usually know a few days ahead of time whom you will be battling against, so the teams would take the opportunity to check each other's robot out and tweak their own strategies in response. Ghost Raptor is an old chassis, but it can be customized by adding on things like extra bars or lifters to try to flip opponents. While this work is all going on, there are camera and production teams wandering around, doing interviews and so on.

When it came time for a match, you bring your robot to the battery tent and put in your power pack, with another safety check by the BattleBots people. Then your robot is weighed: If you exceed the limit of 113 kilograms, something's gotta come off! Then the robot is placed on a cart and brought into the arena—you aren't allowed to drive a robot there under its own power. When it's finally time for the match, the team captain is responsible for turning the key and activating the robot.

This year the arena featured two new wrinkles: There was an upper deck—if you were thrown up onto this deck and couldn't leave before a countdown finished, you lost the match. There were also grinding wheels, called KillSaws, set into the floor which could rip open the underside of a robot, normally its weakest area. As before, the arena also featured "Pulverisers," also known as hammers, that were controlled by opposing teams and could be used to smash up any robot that got too close. The dangers of the arena can matter as much as the characteristics of your opponent. If you are too aggressive in combat, you might find yourself moving so fast that you unexpectedly get knocked under a hammer or into the KillSaws.

For our first match, we were paired against a badass (and very sweet!) team called Combat Robotics at Berkeley and their robot, Glitch. As a rookie team, they had some difficulty getting ready for the match, which caused a seven-day delay, so in the end, Chuck went over and helped them out. During the match, control of Ghost Raptor was spread over the team. Chuck was driving, while other members controlled the flamethrower and lifting bar. My job was to control two of the arena hammers, which was really fun. Smash, smash, yay! Points are awarded based on how much damage you inflict, but of course completely destroying your opponent is always a win.

So how did we do in our first match? Tune in and find out! We'll be giving a breakdown of the fight, along with more technical details of how Ghost Raptor protects itself and dishes out punishment in our next guest blog, and in the meantime, check out more behind-the-scenes photos on our Instagram!

An empty U-shaped set of metal workbenches in a large tent crowded with workspaces


In The Pit, teams had to bring their own equipment, but teams often shared equipment and advice

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