English: Not of very good quality, but illustrates the gimbal lock article quite well.

This is the second of a set of two pictures. This picture shows a plane and a set of gimbals (enlarged for visibility) at the end, where one of the gimbals has moved so to be in the same plane as another one. If the plane rotates along the yaw axis, this won't be reflected anymore on the set of gimbals ("gimbal lock").

Any offer to redraw it is welcome.