The HH-30D Hybrid Hexapod was developed by ALIO Industries to address the inherent performance limitations of conventional hexapods. ALIO’s patented 6-degree-of-freedom (6-DOF) design seamlessly blends and takes advantage of the strengths of serial and parallel kinematic structures while avoiding their weaknesses.
The Hybrid Hexapod offers greater functional versatility, nanometer-level accuracy, repeatability and superior 6-DOF trajectories than is possible with any traditional hexapod or stacked stage configuration. The unique design is comprised of a parallel kinematic tripod to deliver Z plane and tip/tilt motion. This tripod is integrated with a monolithic serial kinematic stage for XY planar motion. A rotary stage integrated into the top of the tripod (or beneath depending on application needs) provides 360-degree continuous yaw (Theta-Z) rotation. In this hybrid design, individual axes can be customized to provide XY travel ranges from millimeters to virtually unlimited ranges while maintaining nanometer-levels of precision. Novel forward and inverse controller kinematics provide an unlimited number of programmable tool center point (TCP) locations.
The HH-30D’s +/-30 degree tip/tilt travel is the most angular travel range available from any 6-DOF positioner on the market, and offers the same unmatched positioning performance found in any of ALIO’s full-line of Hybrid Hexapod systems. Such a large travel range is unprecedented, and it must also be appreciated that this 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.
Furthermore — and as is the case on any Hybrid Hexapod and completely the opposite of any legacy six-legged Hexapod — this large angular range does not consume any notable XY travel when the TCP is set at the default 0,0,0 location (top center). Compare this with any alternative traditional hexapod design, and users of the ALIO solution have at least double the amount of tip and tilt range while still having the full XY and Theta-Z travel available.
The new HH-30D Tripod design leverages ALIO’s experience from the field proven Mini Hybrid Hexapod by using precision ballscrews driven by frameless servo motors. What makes this travel possible is an all-new upper joint design that provides the exceptional travel range in an innovative self-nesting package which keeps the profile extremely low and stiffness very high. Future iterations with this innovative joint can easily incorporate ALIO’s linear motor driven/pneumatically counter balanced links.
The travel range of the tripod is 62 mm, which for applications where only a few degrees of tip/tilt are needed would provide a significant amount of remaining pure vertical (Z) travel. Applications that would directly benefit from the large tip/tilt angle include freeform and aspheric optics metrology, taper angle control in laser micro processing, and additive manufacturing. ALIO has also recognized some precision assembly/packaging applications where large offset angles are needed to “reach” into or around complex spaces.
The HH-30D Tripod can be supplied with virtually any ALIO XY stage to provide a wide range of XY travel options – again, something that is not possible with a standard hexapod. While any XY stage can be used, the company has currently released models for three configurations, including the 60mm XY ballscrew-driven XY from the Mini Hybrid Hexapod, the LM100XY monolithic stage, and the CM200XY low-profile monolithic stage. The two latter configurations come with an umbilical cable management system.
The HH-30D with 60mm XY, 62mm Z and unlimited Theta Z starts at $44,900 (€40,000) with controller, which means the unit is comparably priced with industry alternatives but with features and performance they cannot match. The larger (LM) linear motor-driven version starts at $50,950 (with controller). With 100mm XY travel range and the throughput available from linear motor drives this unit essentially has no meaningful competition.
Related Glossary Terms
- linear motor
Functionally the same as a rotary motor in a machine tool, a linear motor can be thought of as a standard permanent-magnet, rotary-style motor slit axially to the center and then peeled back and laid flat. The major advantage of using a linear motor to drive the axis motion is that it eliminates the inefficiency and mechanical variance caused by the ballscrew assembly system used in most CNC machines.
Science of measurement; the principles on which precision machining, quality control and inspection are based. See precision machining, measurement.
Strip or block of precision-ground stock used to elevate a workpiece, while keeping it parallel to the worktable, to prevent cutter/table contact.
1. On a saw blade, the number of teeth per inch. 2. In threading, the number of threads per inch.
1. Ability of a material or part to resist elastic deflection. 2. The rate of stress with respect to strain; the greater the stress required to produce a given strain, the stiffer the material is said to be. See dynamic stiffness; static stiffness.