he finally struck upon an 81:1 ratio gearbox. It has six gears: five stepped gears and one drive gear on the input shaft. First tests are accomplished with a 3D-printed handle, similar to a hand ...

there are 60 teeth on the input side and 62 on the output, giving a gear ratio of 30:1. The flexible spline is deformed using a set of bearing balls and an elliptical plug on the shaft of the motor.