Nanopositioner’s Tip-and-Tilt Travel Is a Game-Changer

The only 6-Degree-Of-Freedom (6-DOF) nanopositioning device with +/-30 degrees tip-and-tilt travel, the HH-30D Hybrid Hexapod from Alio Industries (Arvada, CO) provides greater functional versatility, accuracy, repeatability, and 6-DOF trajectories than a traditional hexapod or stacked stage configuration.

The hybrid design comprises a parallel kinematic tripod to deliver Z plane and tip/tilt motion that’s integrated with a monolithic serial kinematic stage for XY planar motion. Then, a rotary stage that’s integrated into the top of (or under, depending on application needs) the tripod provides 360-degree continuous yaw (Theta-Z) rotation.

In this way, individual axes can be customized to provide XY travel ranges from millimeters to virtually unlimited ranges while maintaining nanometer-level  precision. Thanks to novel forward and inverse controller kinematics, users can program an unlimited number of tool center point (TCP) locations.

The large travel range is not only unprecedented; the angular range is the full conical motion of the device and not just the available angles from the primary pitch (Theta-Y) and roll (Theta-X) axes. Unlike other six-legged hexapods, the large angular range doesn’t consume any notable XY travel when the TCP is set at the default 0,0,0 location (top center). Compared with traditional hexapod designs, the solution at least doubles the amount of tip and tilt range while still making the full XY and Theta-Z travel available.

The HH-30D Tripod design leverages features from Alio’s field-proven Mini Hybrid Hexapod, including precision ballscrews driven by frameless servo motors. New upper joint design provides exceptional travel range in a self-nesting package that keeps the profile extremely low and stiffness very high. Future iterations with this joint can easily incorporate Alio’s linear motor-driven, pneumatically counterbalanced links.

Applications that would benefit from the large tip/tilt angle include freeform and aspheric optics metrology, taper angle control in laser microprocessing, additive manufacturing, and assembly/packaging applications where large offset angles are needed to “reach” into or around complex spaces. With a 62-mm travel range, a significant amount of pure vertical (Z) travel remains for applications where only a few degrees of tip/tilt are needed.

The tripod can be supplied with virtually any Alio XY stage to provide a wide range of XY travel options, but models for three configurations have been released: the 60-mm ballscrew-driven XY from the Mini Hybrid Hexapod, the LM100XY monolithic stage, and the CM200XY low-profile monolithic stage. The latter two come with an umbilical cable management system.

The HH-30D with 60mm XY, 62mm Z, and unlimited Theta Z starts at $44,900 with controller. The larger (LM) linear motor-driven version with controller and  featuring100mm XY travel range starts at $50,950.

www.alioindustries.com