Hardware engineer Mike Choi’s love for tinkering comes from his love for Nintendo products. His appreciation for everything the publisher creates inspired his ludicrous, but fully functional, multipart device dubbed the “Labo Fit Adventure Kart Kit.” The Kart Kit lets players use a stationary exercise bike and Ring Fit controller to play the Nintendo Switch video game “Mario Kart 8 Deluxe.”

“I grew up playing video games,” Choi said. “A big formative part of my identity as an engineer and as a professional is how much Nintendo has influenced me. They’re always doing weird things with their hardware and interesting things that are totally out of left field.”

Choi, 27, who resides in the San Francisco Bay area, doesn’t consider himself an “exercise conscious” person, but he nonetheless has a fascination with fitness games. Most aren’t compelling, he says, never keeping his attention for more than a few weeks, leading him to create something of his own.

“I think at the core of it is, how can you exercise without feeling like you’re exercising?” Choi said.

His creation — which is shown in a 24-minute YouTube parody of a Nintendo commercial — involves holding a Ring-Con like a steering wheel (it can also be squeezed to shoot at enemies) while pedaling on a stationary bike to accelerate an in-game Kart.

Everything that you see in the video is real,” he said. “It works the way that I described it. I’ve been using it.”

The lengthy video breaks down how Choi built his “Labo Fit Adventure Kart Kit.” The heart of his creation is TAPBO, a small robotic device he engineered that holds the Joy-Con in place and has motorized arms that press down on two of the controller’s buttons for accelerating and slowing down in “Mario Kart 8 Deluxe.” To play, you sit on the bike (which he comically calls the Bike-Con and covered in cardboard to resemble Nintendo Labo’s line of products), hold the Ring-Con in both hands like a steering wheel, and pedal to move forward.

I didn’t want to mod any software,” he said. “I didn’t want to emulate a Joy-Con or have to do any of that kind of thing. None of the hardware is modded. It’s pretty primitive in the sense that it’s just a robot pressing buttons.”

The robot, TAPBO, is inspired by a Nintendo product from the mid-1980s called “R.O.B. the Robot,” a toy robot that, just like TAPBO, essentially presses buttons on a controller in lieu of the player.

For the “Labo Fit Adventure Kart Kit,” the TAPBO communicates with the bike, which has its own custom circuit inside to properly communicate with both the Ring-Con and the Nintendo Switch. For example, once you reach a specific speed threshold by pedaling, it activates the TAPBO to press on the acceleration button on the Joy-Con to move your Kart forward. For the Ring-Con, Choi added his own sensor to the controller, which translates the player’s movements to in-game actions.

The Ring-Con looks just like a steering wheel, just like the Wii Wheel,” he said. “That was a pretty easy solution to get the tilt controls to work. Getting the squeezing to translate to shooting items was a lot more difficult, but felt like that was the key to make it like a full-body workout.”

At one point, he considered programming the TAPBO to completely turn off the Nintendo Switch, essentially acting as a power button, if the player is unable to maintain a certain speed. In the end, though, he felt it would be too punishing.

One of the reasons Choi decided not to personally mod any software or hardware was because of Nintendo’s strict stance against fan-made mods of their products, often firing off cease and desists to fan-made projects. He’s feared his own YouTube video may be removed, despite its explicit mention that it contains no modded content.

It’s no secret, especially right now, that Nintendo has not been a huge fan of fans creating their own projects,” Choi said.

It’s not the first time Choi adapted a Nintendo product or engineered third-party accessories. He engineered the Flip Grip, a popular, third-party handheld accessory that flips the screen 90 degrees. This is incredibly helpful for dozens of Switch games that are best played vertically, including arcade ports for “Punch-Out” and “Donkey Kong.”

Although “Labo Fit Adventure Kart Kit” has no modded hardware or software, it can still be considered part of an online community subset dedicated to adapting video game controllers. Choi points to other creations, including a mod that allows users to play “Legend of Zelda: Breath of the Wild” with a Ring-Con, which Choi believes is “wicked cool.” Most recently, he was sent a video showing someone on an exercise bike that was designed to control a GameCube.

Choi grew up not just on Nintendo games as a whole but has long been a fan of “Mario Kart.” His creation took six months of tireless work to build, but he feels the result was worth the time and effort, giving him a new way to interact with the game and offering a new way to get fit.

I think attaching exercise to that, for me, it definitely makes sense,” he said. “If anything is going to get me to exercise, it’s going to be that.”

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