Parallel Kinematic Piezoelectric Stage

The PKA-ZPR-200 nanopositioning stage was developed for active alignment correction.  It uses a parallel kinematic architecture for high stiffness and high resonant frequency with one translational degree of freedom and two rotational degrees of freedom. It features flexure-guided motion over a nominal 200 um displacement range.  Rotational range of motion is greater than 4 mrad.  The stage’s stable and stiff kinematic design promotes dynamic responsiveness for excellent position stability and control.  It is designed to include high-resolution metrology that, when combined with a suitable 3 channel low-noise piezoelectric amplifier, can deliver position resolution of 10 nm or better.

Specifications 

Open-Loop Travel: 200 micron linear in Z; > 4 mrad rotary X & Y
Closed-Loop Resolution: Metrology dependent 10 nanometers typical with capacitive probe
Unloaded Resonant Freq: >590 Hz
Resonant Freq with 50g: >280 Hz
Electrical Capacitance: 8 µF per channel
Operating Temp Range: 25 to 50 degrees Celsius
Dimensions: 72 mm diameter by 44 mm tall
Material: Stainless steel or titanium
Ultra-High Vacuum Compatible

Highlights of the PKA Stage Design

  • Flexure-guided for smooth, parallel motion
  • Option for integrated metrology
  • High natural frequencies and rapid response
  • Linear displacement range of 200 µm
  • Angular displacement > 4 milliradians
  • Customizable and scalable for new applications

Applications

Parallel kinematic mechanisms are recommended for applications where high natural frequency and stiffness are needed with multiple degrees of freedom.  Control of parallel kinematics is more complicated than stacked serial stages, so parallel kinematic designs are generally reserved for high performance systems.