Posted to News on 25th Jun 2011, 12:35
Aerotech AXR series two-axis rotary micropositioning units
Aerotech's new AXR series two-axis rotary micropositioning units combine yaw and tilt axes for high-speed, high-throughput micromachining of complex 3D structures such as MEMS components. As part of the enabling technology for many microfabrication techniques, the rotary assembly provides an accurate platform for positioning and manipulation from a precision-aligned hemispherical surface.
With two standard module sizes offering nominal system loads of 15kg or 30kg, the AXR includes a direct-drive yaw (B) axis capable of unlimited rotation up to 1000rpm with a sub-arc-sec position resolution. The second tilt (A) axis offers a fixed rotation over -10 to +100 degrees and is available with brushless servomotor direct-drive for high-speed positioning to 720degrees/s, or for the larger sized version as a servomotor-driven geared option with an anti-backlash harmonic gearbox that offers a much higher continuous torque that will suit heavier load applications where slower operation and reduced overall accuracy are acceptable.
As with all of Aerotech's precision mechanics, customers have a choice of calibrated and uncalibrated versions to match their application requirements, thereby ensuring competitive and economical system costs. Throughout the range, high line-count optical encoders offer angular resolution to 0.04arc-sec and, with multiplier and advanced amplifier technologies, help to ensure smooth motion and excellent position stability for exacting micromachining. With HALAR calibration, the all-direct-drive version of the AXR can provide a +/-3arc-sec positional accuracy while the geared version has a +/-5arc-sec accuracy. Bi-directional repeatability across the direct-drive versions is +/-1arc-sec, compared with geared versions' +/-5arc-sec. Uncalibrated specifications for accuracy are +/-30arc-sec for the direct-drive version and +/-50arc-sec for the geared version.
Workholding options
The AXR series features an integral pneumatic rotary union for vacuum or air-activated work holding, and the ready-to-run assembly includes motor and feedback cables and connectors. Both module sizes may be ordered in a choice of configurations where the yaw axis tabletop is either at the centre of rotation of the tilt axis or offset at 100mm below the centre of rotation for the smaller assembly or 125mm for the larger version. The orthogonal mounting accuracy is within 10arc-sec.
All configurations are offered with a sealing option for increased protection against dust and dirt. Further options include a counterweight attachment to help balance offset loads, a manual three-jaw chuck for the yaw axis for workpiece clamping, and a pneumatic locking brake fitted to the tilt axis that limits stage motion during micromachining.
The durable black-anodised aluminium construction includes a yaw axis tabletop with a matrix of M5 Helicoil inserts for mounting fixtures. Heavy-duty, high-precision bearings help to ensure units enjoy a long operating life with low maintenance; an MTBF of 20,000 hours is quoted for the non-contacting, direct-drive version, and 15,000 hours for the geared version.
Aerotech developed the AXR series as part of its laser and medical industry offering. This includes a wide range of micropositioning mechanics that combine with advanced motion controls to help produce complex components at fast production throughput without compromising quality or accuracy. The AXR joins linear/rotary axis configuration designs such as the LaserTurn and Vasculathe for the manufacture of stents and other cylindrical components.
AXR series two-axis rotary micropositioning assemblies are typically supplied as a part of a complete motion control subsystem with Aerotech's advanced motion controls and servo amplifiers. HALAR-calibrated versions include an error compensation lookup chart that is stored within the controller to ensure optimum accuracy performance.
Aerotech's motion controls include the PC-based A3200 Digital Automation Platform , the MotionPAC programmable automation controller, and the Ensemble and Soloist standalone motion controllers. Throughout the range, PC-based software-only control or standalone systems are available in rack- or desk-mounted versions. Aerotech's wide choice of machine controls and sophisticated motion commands include IEC 61131-3, Microsoft .NET Framework and LabVIEW programming capability, with advanced software and analytical functions that are designed to optimise machine performance, increase precision and improve throughput. Contact Aerotech now for more information about the AXR series two-axis rotary micropositioning units.
