The Car Flip Mechanism is Wild

How does a piece of fishing line make this car roll?
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One crank runs the whole stunt through a 9:1 gear train. Two cam grooves in the back plate control the car. One tilts it to match the ramp, and the other is a timer that swings a small rocker right after the car leaves the ramp.
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That swing becomes the roll through a capstan. A loop of braided fishing line runs from a drum on the rocker, up the tube, and around the car’s axle. The drum is 2.4 times bigger, so 75° of swing turns into exactly 180° of roll.
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The full breakdown, with a 3D model you can crank yourself, is at https://engineezy.com/blogs/project-details/how-the-roadster-ramp-flip-works
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