The BGM120BPP is a motorized goniometric cradle offering ±45° of transverse axis rotation with a micro-step drive for high angular speeds up to 20°/s. It features a precision ground worm gear drive with 0.002° minimum incremental motion, a worm-mounted rotary encoder for improved repeatability, and mechanical limit switches at ±45°. The stage uses single-row ball bearings with hardened tool-steel races for smooth motion and stability, and has a normal centered load capacity of 200 N. Its base material is stainless steel with an aluminum body, and it supports direct orthogonal stacking with adjacent-sized cradles. The encoder provides an index pulse for precision homing, and the maximum torque is 6 Nm. The unit includes a 3 m cable.
The BGM120BPP Goniometer 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. This PP mini-step drive version enables high angular speeds up to 20°/sec .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.
Precision Multi-Axis Assemblies
BG goniometers are designed so that two adjacent-sized models can be directly mounted orthogonally to each other (for example, BGS80 with BGM120) to pivot about the same point in space. The direct mounting capability saves set-up time, design time, and adapter plate costs. For additional rotation axes, a rotation stage can be mounted under the assembly or on the top BG platform. The video demonstrates an open access, multi-axis tip, tilt and rotation assembly with two BG goniometers and two rotation stages.
Open Rotation Platform
The BG series stages provide up to ±45° of transverse axis rotation enforced with mechanical limit switches. The stage is designed for maximum free access to the rotating platform, allowing for simplified stacking and mounting.
Precision Worm Gear Drive
Precise rotation is ensured by a precision ground, hardened worm gear drive. In addition to being non-backdrivable, the worm gear drive's advantages include higher MIM, repeatability, and overall accuracy.
Ball Bearings with Tool-Steel Races
Single-row ball bearings and precision-ground, hardened tool-steel races ensure smooth rotation with minimal wobble and eccentricity. This allows for higher load capacities, stiffness, and stability.
Stepper Motor Versions
The PP and BPP mini-step drive versions are for applications that require higher speeds. For higher torque and vacuum applications, the PE and BPE full-step drive versions are recommended.
Basic working principle of a stepper motor
| Newport MKS | |
|---|---|
| Product Category | Rotary Stages |
| Product Number | BGM120BPP |
| Product Name | Motorized Goniometer, ±45° Travel Range, Micro-step Drive, BGM120 |
| Stage Type | Cradle Positioning / Goniometer |
