Bookmark this site
 Deutsch

Download / Support
Technotes
NanoInnovation Grant™

 
500 page PI Catalog

Get the hardbound, 500
    page PI Catalog



M-850 Hexapod shown in
different positions.
Parallel Kinematics (PKM) In Precision Motion Control Applications

>> White Paper Parallel Kinematics With Sub-µm Precision
>> White Paper Parallel Kinematics With Extremely Small Hysteresis


Advantages of Parallel Kinematics (PKM)
Micro- and Nanopositioning Systems:
Example: 6-Axis Parallel-Kinematics Micropositioning Systems
vs. Serial Kinematics (Stacked) Systems
  • Lower Inertia
  • Better Dynamic Behavior
  • Smaller Package Size
  • Higher Stiffness
  • No Accumulation of Position Errors
  • Reduced Runout Errors
  • No Moving Cables: Better Repeatability and
    Reliability
>> More Information on Hexapods
Watch In-Plane Tripod Animation below.

Watch M-840 Hexapod in Motion Video below.
>> More Information on Hexapods


Parallel Kinematics Hexapod Robot 6-Axis MicroPositioning System.

  • Six actuators support only one lightweight platform. 
  • Much higher stiffnes, reduced inertia 
  • No accumulation of runout errors. 
  • Virtual center of rotation, set by one software command. 
  • No dragged cables, no cable tension/ management issues: better reliability & higher repeatability  
>> Download Hexapod Brochure

Serial-Kinematics "Stacked" 6-Axis Stage.

  • The bottom stage supports its own moving platform plus all stages above. 
  • Runout errors and tilt errors accumulate. 
  • Up to 5 moving cables cause friction and cable management problems. 

Tripod and Bipod Parallel-Kinematic Piezo-Systems (Nanopositioning Stages)

Serial Kinematics vs. Parallel Kinematics in Nanopositioning Systems


Parallel Kinematic Flexure Nanopositioning System
(In-Plane Tripod)
  • Same ultra-low inertia for X and Y motion, providing higher responsiveness and axis-independent performance. 
  • Excellent, mounting independent orthogonality. 
  • Reduced runout: X sensor (PI uses non-contact two plate capacitance sensors) can monitor and correct for Y runout and vice versa (Active Trajectory Control). 
  • Additional rotation axis (Theta Z) feasible with 3 actuators / sensors and digital controller.
Stacked Serial Kinematics Flexure Nanopositioning System
  • Simple Design, but: 
  • Slower response (lower stage carries inertial mass of upper stage);
  • Non-symmetric resonant frequencies (lower stage is slower than upper stage, requires different servo settings).
  • Orthogonality error is mounting-angle dependant.
  • Runout in Y cannot be monitored/compensated by the sensor in the X stage or vice versa. 
Nested Serial Kinematics Flexure Nanopositioning System
  • Thinner and better response than Stacked Serial Kinematics, but no other advantages

Examples of Parallel Kinematics Nanopositioning Systems


Tripod  Nanoposititioning Stage P-587 Nanopositioning Stage P-733 XY Nanopositioning Stage
Tripod Z/Tip/Tilt Stage,
Clear Aperture.
P-587 6-DOF Most Advanced
    Six-Axis Nanopositioning Stage.
    Travel to 800 µm and 10 mrad.
P-733 XY Nanopositioning
   Stage. Capacitive Feedback,
   Clear Aperture.

P-734 Nanopositioning Stage 541 Piezo Scanning Stage P-714 Low-Profile XY Scanner
P-734 Ultra-High Flatness XY
    Nanopositioning Stage. Capacitive
    Feedback, Clear Aperture.
P-541 Low-Profile, Z/Tip/Tilt
    Tripod Piezo Scanning Stages for
    Microscopy. To 200µm
    Travel Range. Clear Aperture
P-714 Low-Profile XY Scanners for
    Imaging.Compact Size, Highly Cost-
    Efficient Design, Clear Aperture.



Examples of Parallel Kinematic Steering Mirrors (Active Optics)

Parallel Kinematics Differential DriveTriple-Piezo-Drive Active Optics Platform
Parallel Kinematics
    Differential Drive
Tripod-Piezo-Drive Active Optics Platform Featuring
    3 Actuators (Tripod) and 4 Sensors

S-330 Piezo Tip/Tilt Platforms S-316 3-Axis Steering Mirror Active Tip/Tilt mirror for Subaru Telescope
S-330 Ultra-Fast Piezo
    Tip/Tilt Platforms
S-316 High-Speed, Tripod Tip/Tilt
    Steering Mirror
Active Tip/Tilt mirror for Subaru
    Telescope (Mauna Kea, Hawaii).







Micro-Hexapod · Piezo-Motor Hexapod · Piezo · Nanopositioning Catalog · Piezo Nano-Positioning and Parallel Kinematics · PI USA · Capacitance Sensors ·Nanoautomation ·Micropositioners ·Hexapod Datasheets · ·Parallel-Kinematics Stage · ·Piezo Stage · PI Ceramic Piezoceramic Materials ·PIFOC® Piezo-Z Focus Scanner ·Ultrasonic Piezo- Motor ·Multilayer Piezo