Planetary Gear - Educational model

My Educational Mechanical Examples SeriesThis model is one of my educational mechanical mechanism examples on 80mm x 80mm base plates.You can find all models of the series in this collection => [Mechanical Mechanism Examples]The present modelThis is an educational model of the Planetary Gear.Brief DescriptionA planetary gear can achieve a high reduction ratio in a compact, coaxial configuration. In this model, the small central spur gear—the sun gear—serves as the input, while the planetary carrier, the rotatable table on the backside that holds the three larger spur gears (the planet gears), serves as the output. The surrounding internal gear is fixed to the base plate. When the sun gear rotates, the planet gears rotate on their own axes (self-rotation) while simultaneously revolving around the sun gear. This revolution corresponds to the rotation of the backside table, which becomes the output motion. In this model, the sun gear has 9 teeth, each planet gear has 15 teeth, and the int