The model BGM200PP features a worm mounted rotary encoder for improved accuracy and repeatability. The encoder also provides a method for detecting motor stalling, an important feature for applications with high loads or torques. BG Series goniometric cradles rotate on a transverse axis above the platform. Compared to full 360 ° rotation stages, they offer maximum free access to the rotating part and allow construction of very compact multi-axis rotation assemblies. BG cradles are designed so that orthogonal mounting of two adjacent-size cradles (e.g., BGS50 and BGS80) provides two perpendicular rotational axes intersecting at about the same point in space. Mounting a rotation stage under the assembly adds a third orthogonal rotation axis through the same point. Precision rotation is ensured by a precision ground, hardened worm gear drive. Single row ball bearings and precision ground tool-steel races ensure smooth rotation with minimal wobble and eccentricity. A home switch, conveniently located at the center of travel, facilitates the return of the platform to a level position.