This Crazy YouTuber Built a Real-Life, Fully-Functional Motorized Grappling Gun

Grappling guns are a hallmark of action-themed fiction — practically a requirement when the commando-hacker-spy protagonist needs to infiltrate the baddies’ stronghold. Grappling guns are also real things that actually exist, though they definitely aren’t the kind of everyday tactical gear that movies and video games pretend they are. At their simplest, you just have a grappling hook attached to a rope that you can throw and then climb. But doing so requires physical exertion and nobody wants that. To ascend to fortress rooftops with ease, YouTuber JT Jameson built a real-life, fully-functional motorized grappling gun that really works in the real-world, for real.

Unless you have your own personal Q or access to wherever Navy SEALs do their shopping, you probably can’t just go purchase a grappling gun like this. There are commercial motorized ascenders on the market, but those are intended for recreational or commercial climbing and don’t fire grappling hooks in the way you picture when you hear the term “grappling gun.” This unfortunate reality forced Jameson to build his own and the results are very impressive. The grappling gun attaches to Jameson’s forearm and it is surprisingly compact. All he has to do is point and shoot, which causes the grappling hook to fly up several yards. Once it is properly anchored, Jameson can use a thumb-operated throttle to winch himself up. He can either hang from the built-in handle or attach the device to a conventional climbing harness to zip upward in comfort.

As you would imagine, it takes quite a lot of torque to lift a full-grown man up. To handle that, Jameson’s grappling gun uses a beefy 14-pole brushless outrunner motor that is intended for driving electric skateboards. It is geared down 9:1 to increase the torque. The motor is controlled by a huge 200A ESC through an Arduino Nano on a custom PCB. The ESC even supports regen, so the battery can be partially recharged during descent. That is very useful since the battery pack is fairly small, with just two LiPo batteries providing a total capacity of 1800mAh setup at 12s. The grappling hook is attached to the rest of the device by a spool of paracord and is fired pneumatically with 800 PSI of pressure from the same kind of small CO2 cartridges that you would use for airsoft guns.

The frame of the grappling gun needed to be strong, so Jameson constructed it from a combination of custom-fabricated aluminum and steel parts. The grappling gun was tested in both a climbing gym with very accommodating management and on park trees with spectacular results. Jameson was able to ascend 10 meters in just three seconds, which is incredibly impressive performance. He may not be the first person to build this kind of grappling gun, but his is the best that we’ve seen and it is safe to assume that Batman will be getting in touch with Jameson to place some discrete orders soon.