This awesome bit of gearing has appeared on HowStuffWorks just before. You could possibly identify it from the electric screwdriver article. An automatic transmission is made up of two total planetary gearsets folded alongside one another into a single ingredient. See How Gear Ratios Do the job for an introduction https://charlierchjo.elbloglibre.com/34123616/not-known-facts-about-gearbox-auto