- ProductsProductsPI is a worldwide leading supplier of solutions in the fields of motion and positioning. PI does not only develop and produce a broad range of positioning stages and actuators for linear, rotary and vertical motion or combinations of different axes. PI also adapts those solutions to customer-specific applications or supplies finished subsystems for motion and positioning.
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- Product FinderProduct FinderSelect the product type specified by the axes of motion required. Selection of more criteria expands or shortens the list of results. Select more than one filter at a time, for example, to find positioning stages designed for higher load capacity, too.
- Customized ProductsCustomized ProductsPI is fully at home where unconventional solutions are in demand. This is no longer limited to fields of research. Today, nanotechnology is also present in standardized industrial processes.
- Nanopositioning Piezo Flexure StagesNanopositioning Piezo Flexure StagesPI's piezo flexure stages combine sub-nanometer resolution and guiding precision with minimum crosstalk.
- Multi-Axis Piezo Flexure StagesMulti-Axis Piezo Flexure Stages
- PIFOC® Objective & PInano® Sample Scanners for MicroscopyPIFOC® Objective & PInano® Sample Scanners for Microscopy
- Linear Piezo Flexure StagesLinear Piezo Flexure Stages
- XY Piezo Flexure StagesXY Piezo Flexure Stages
- XYZ Piezo Flexure ScannersXYZ Piezo Flexure Scanners3-Axis Nanopositioning Scanners of Maximum Precision
- Piezo Flexure Tilting MirrorsPiezo Flexure Tilting Mirrors
- Multi-Axis Piezo Flexure Stages
- Miniature StagesMiniature StagesMiniaturized stages and manipulators are essential in mobile applications for measuring and medical devices, in industrial microassembly or use for research, e.g. in UHV and non-magnetic environments.
- Miniature Linear StagesMiniature Linear Stages
- Miniature Rotation StagesMiniature Rotation Stages
- Miniature HexapodsMiniature Hexapods
- Miniature Linear Stages
- Linear StagesLinear StagesPI offers a wide range of motorized linear stages to supply high-precision industrial markets like semiconductor and photonics, as well as high-end research. Vacuum versions are available for a large number of different models. Multi-axis compositions can be set up with adapter brackets or specialized vertical stages and compatible rotation stages.
- Stages with Magnetic Direct-Drive Linear MotorStages with Magnetic Direct-Drive Linear Motor
- Stages with Stepper, DC & Brushless DC (BLDC) MotorsStages with Stepper, DC & Brushless DC (BLDC) Motors
- Vertical Stages with Stepper, DC & Brushless DC (BLDC) MotorsVertical Stages with Stepper, DC & Brushless DC (BLDC) Motors
- Miniature Linear StagesMiniature Linear Stages
- Stages with Magnetic Direct-Drive Linear Motor
- Linear ActuatorsLinear ActuatorsChoose from the widest range of technologies the optimum for your special demands: Set-and-forget applications benefit from the specific features of piezomotors that provide excellent long-term stability, also for vacuum or nonmagnetic environments. Stepper and DC motor solutions are well-established and reliable for both industrial and research use.
- PiezoMike for Long-Term StabilityPiezoMike for Long-Term Stability
- Linear Actuators with Stepper & DC Servo MotorsLinear Actuators with Stepper & DC Servo Motors
- Voice Coil Actuators with High Dynamics & Force Control OptionVoice Coil Actuators with High Dynamics & Force Control Option
- PiezoMove Lever ActuatorsPiezoMove Lever Actuators
- Nanopositioning Piezo ActuatorsNanopositioning Piezo Actuators
- PiezoWalk® Actuators with High Force & StabilityPiezoWalk® Actuators with High Force & Stability
- PIRest Active Piezo ShimsPIRest Active Piezo Shims
- PiezoMike for Long-Term Stability
- Rotation StagesRotation StagesPI offers stages with all kinds of motorization and guiding options: air-bearing, torque motor driven, motorized worm-gear coupled, tiny piezomotor stages and specialized goniometer stages with orthogonal tip-tilt mounting option.
- XY StagesXY StagesStability, precision and dynamics are crucial in the application fields of PI’s XY stages. They are the basis of high throughput rates and reliable operation. PI makes use of own developments in the fields of PIMag® magnetic linear motors and PIglide air bearings. Industrial production and quality control benefit from PI’s high-load XY stages and planar scanners.
- HexapodsHexapodsHexapods provide six degrees of freedom in the most compact package. In combination with absolute measuring sensors, software and motion controllers that make the most complicated motion profiles easy to command, PI hexapods answer industrial requirements.
- Engineered Subsystems for AutomationEngineered Subsystems for AutomationPrecision components, stable control and a great deal of experience in engineering are essential for high-precision complex motion and positioning solutions. PI is a supplier of technologically sophisticated drive components and high-precision positioners and also offers all levels of integration for engineered subsystems.
- Fast Multi-Channel Photonics AlignmentFast Multi-Channel Photonics Alignment SystemsPiezo scanners take care of fast, continuous scanning tasks, where durability, dynamics, and precision matter. The larger travel ranges are realized with XYZ combinations or 6-axis hexapods. Integrated routines make it possible to perform single-axis alignments up to complex, multi-axis fiber array positioning within the shortest possible time.
- Motion Control SoftwareMotion Control SoftwareAll digital controllers made by PI are accompanied by an extensive software package.
- User Programs and Their FunctionsUser Programs and Their Functions
- Software Tools for HexapodsSoftware Tools for Hexapods
- Third Party SupportThird Party Support
- Software Products for Special ApplicationsSoftware Products for Special Applications
- Controllers & DriversControllers & DriversThe decision for a motion controller depends on the specific application situation. Various criteria, such as limited installation space, the number of axes or the type of control, determine which controller is the right one. PI offers a broad spectrum of controls and regulation concepts.
- Nanopositioning Piezo ControllersNanopositioning Piezo Controllers
- Piezo Drivers for Open-Loop Operation of Piezo ActuatorsPiezo Drivers for Open-Loop Operation of Piezo Actuators
- Motion Controllers & Drivers for Linear, Torque, Stepper & DC Servo MotorsMotion Controllers & Drivers for Linear, Torque, Stepper & DC Servo Motors
- Controllers & Drivers for PiezomotorsControllers & Drivers for Piezomotors
- Controller Systems for Multiple Axes & Mixed Drive TypesController Systems for Multiple Axes & Mixed Drive Types
- Hexapod Motion ControllersHexapod Motion Controllers
- ACS Motion ControlACS Motion Control for Industrial Automation
- Nanopositioning Piezo Controllers
- Piezoelectric Transducers & ActuatorsPiezoelectric Transducers & ActuatorsPiezoelectric ultrasonic transducers are available in a wide range of shapes like disks, plates or tubes, and different performance levels. They can be adapted to application requirements by using different piezoceramic materials, electrodes, and assembling technology.
- Discs, Rods and CylindersPiezoceramic Discs, Rods & Cylinders
- Plates and BlocksPiezoceramic Plates & Blocks
- RingsPiezoceramic Rings
- TubesPiezoceramic Tubes
- Spheres and HemispheresPiezoceramic Spheres & Hemispheres
- Bending ElementsPiezoceramic Bending Elements
- Tube ActuatorsPiezo Tube Actuators
- PICMA® Piezo Linear ActuatorsPICMA® Piezo Linear Actuators
- PICMA® Piezo Bender ActuatorsPICMA® Piezo Bender Actuators
- PICA Piezoelectric Stack ActuatorsPICA Piezoelectric Stack Actuators
- PICA Shear ActuatorsPICA Shear Actuators
- DuraAct Patch TransducersDuraAct Patch Transducers
- Picoactuator® Piezoelectric CrystalPicoactuator® Piezoelectric Crystal
- Discs, Rods and Cylinders
- Air Bearings & StagesAir Bearings & StagesAir bearing stages are used where vibration-free motion is required, velocity needs to be highly constant, and optimum angular repeatability is requested.
- Sensors, Components & AccessoriesSensors, Components & Accessories
- VacuumProduct Series with Vacuum-Ready ItemsPI offers specific catalogue items for selected product series that are already suitable for high vacuum (HV) or ultra-high vacuum (UHV).
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- OEMOEMCustomer- and application-specific product developments form the basis for success at PI. To this purpose, requirements have to be understood and a technological solution has to be found.
- ApplicationsApplications & MarketsPI positioning systems are employed where technology is pushed forward in industry and research. This is done, for example, in semiconductor manufacturing, in medical engineering, in biotechnology, in plant engineering, in surface metrology, or in astronomy.
- Hexapods Support Industrial RobotsHexapods Support Industrial Robots
- Scientific InstrumentationScientific Instrumentation
- Hexapod Systems for ALMAHexapod Systems for ALMA
- Double-Crystal MonochromatorDouble-Crystal Monochromator for an X-Ray Spectrometer
- Materials Research in High VacuumMaterials Research in High Vacuum
- Active Vibration Isolation with Piezo ActuatorsActive Vibration Isolation with Piezo Actuators
- Drive Technology for the ELTDrive Technology for the ELT
- Hexapod Systems for ALMA
- Semiconductor TechnologySemiconductor Technology
- Confocal MicroscopyAdjustment of the Focal Planes in Confocal Microscopy
- Positioning Solutions for Total Internal Reflection Fluorescence Microscopy (TIRFM)Positioning Solutions for Total Internal Reflection Fluorescence Microscopy (TIRFM)
- High-Speed MicroscopyHigh-Speed Microscopy for Quality Control
- Atomic Force MicroscopyAFM Scanner for Atomic Force Microscopy
- White Light Interferometry3-D Surface Inspection With Piezo-Based Positioning Systems from PI
- Flamingo Lightsheet Fluorescence MicroscopyFlamingo Lightsheet Fluorescence Microscopy
- IsoView Light Sheet MicroscopeIsoView Light Sheet Microscope
- Confocal Microscopy
- Silicon PhotonicsSilicon Photonics
- Photonics PackagingAutomated Photonics Packaging
- Optical Fiber AlignmentSimultaneous Testing of Optical Components in Silicon Photonics
- Photonics Packaging
- Medical TechnologyMedical Technology
- EndoscopyVariable Focusing and Sharp Focus for Endoscopic Applications
- Surgical Robots for OphthalmologySurgical Robots for Ophthalmology
- Magnetic Resonance ImagingNonsensitive Drives for Magnetic Resonance Tomography
- Optical Coherence TomographyPiezo Technology and Optical Coherence Tomography (OCT)
- PipettingPiezomotors for Pipetting and Nanodispensing
- Precision DosingDynamic Drives for Precision Dosing with Nanodispensers
- MicropumpsPiezoelectric Micropumps – Compact Design and High Performance
- Image StabilizationImage Stabilization and Microscanning with Piezo Scanners
- Adaptive Diaphragm PositioningAdaptive Diaphragm Positioning
- Positioning Solutions for Whole Genome SequencingPositioning Solutions for Whole Genome Sequencing
- Materials ResearchMaterials Research
- Parallel Kinematics for Materials ResearchHigh-Load Parallel Kinematics for Materials Research
- Laser Beam ControlPiezo Drives for Laser Beam Control
- Parallel Kinematics for Materials Research
- Mechanical EngineeringMechanical Engineering
- Electrical Discharge MachiningPiezo Actuators Accelerate Electrical Discharge Machining
- Hexapods in Mechanical EngineeringHexapods in Mechanical Engineering
- Electrical Discharge Machining
- Smarter Motion PositioningSmarter Motion Positioning
- Hexapods in MicroproductionHexapods in Microproduction
- Hexapods for Quality AssuranceHexapods for Quality Assurance
- Magnetic Direct DrivesMagnetic Direct Drives
- Motion Simulation with HexapodsMotion Simulation with Hexapods
- Flexibility in Dimensional MeasuringHexapod Systems in Automation
- Motion Compensation with HexapodsMotion Compensation with HexapodsDynamic hexapods with piezo drives: Best conditions for motion compensation.
- Fast Piezo Ultrasonic Drives Advance TechnologyFast Piezo Ultrasonic Drives Advance Technology
- Laser Material ProcessingLaser Material Processing
- Hexapods for Optical MetrologyHexapods Support Precise Measurement of Aspheres
- Smarter Motion Positioning
- Beamline InstrumentationBeamline Instrumentation
- Tomography EquipmentTomography Equipment
- Synchrotron Spectroscopy in VacuumSynchrotron Spectroscopy in Vacuum
- Beam PreparationBeam Preparation
- Sample Positioning for TomographySample Positioning for Tomography
- Accelerator TechnologyAccelerator Technology
- Tomography Equipment
- Additive ManufacturingAdditive Manufacturing
- Active AlignmentActive Alignment
- TechnologyKnow-How & TechnologyPI combines its long-term experience in micro and nanopositioning technology with in-depth knowledge in the fields of mechanics, electronics, sensor engineering, and software. Thus, PI is able to offer its customers the most advanced drive technologies and system solutions.
- Piezo TechnologyPiezo TechnologyPI Ceramic offers a wealth of experience in the manufacturing of piezoceramic materials, components, and actuators. The piezoceramic materials can be adapted individually to perfectly fit the later use of the piezo components.
- Fundamentals of Piezo TechnologyFundamentals of Piezo TechnologyPhysical basics and explanations of piezo electricity and electromechanics.
- Properties of Piezo ActuatorsProperties of Piezo Actuators
- Piezoceramic MaterialsPiezoceramic MaterialsPI Ceramic offers a variety of different piezoelectric materials including lead-free materials.
- Manufacturing TechnologyManufacturing Technology
- PICMA® TechnologyPICMA® Technology
- Integrated Piezo ActuatorsIntegrated Piezo Actuators
- DuraAct Patch Transducer TechnologyDuraAct Patch Transducer Technology
- PIRest ActuatorsPIRest ActuatorsActive shims with long-term stability and nanometer resolution.
- Fundamentals of Piezo Technology
- Piezoelectric DrivesPiezoelectric DrivesDepending on the configuration and control, piezoceramic actuators can be used to create translational motions or as motors with a virtually unlimited travel range. The choice of drive depends on the requirements of the application.
- Piezo ActuatorsPiezo Actuators with and without Guiding
- PiezoWalk® Walking DrivesPiezoWalk® Walking Drives
- PILine® Ultrasonic PiezomotorsPILine® Ultrasonic Piezomotors
- Piezo Inertia DrivesPiezo Inertia Drives
- PiezoMike Linear ActuatorsPiezoMike Linear Actuators
- Comparison: Piezo Motors & Drive TechnologiesComparison: Piezo Motors & Drive Technologies
- Piezo Actuators
- Electromagnetic DrivesElectromagnetic DrivesRotating electric motors such as DC or stepper motors are used in connection with screw or worm drives. Stepper motor systems with high-resolution encoders can perform minimum incremental motions of 10 nm with high reliability and repeatability.
- Rotating Electric MotorsRotating Electric Motors from PI
- Magnetic Direct DrivesMagnetic Direct Drives
- PIMag® 6-D Magnetic LevitationPIMag® 6-D Magnetic Levitation at Six Levels of Freedom
- Hybrid ConceptPiezo & Motor Hybrid Concept
- Rotating Electric Motors
- Parallel KinematicsParallel KinematicsIn a parallel-kinematic, multi-axis system, all actuators act directly on a single moving platform. This means that all axes can be designed with identical dynamic properties, thus reducing the moved mass considerably. Hexapods are used for moving and precision positioning, aligning and displacing loads in all six degrees of freedom, i.e., three linear and three rotational axes.
- Parallel KinematicsPiezo Positioning Systems with Parallel KinematicsIn a parallel-kinematic, multi-axis system, all actuators act directly on a single moving platform.
- Multi-Axis PositionersMulti-Axis Positioners and Stewart Platforms
- Hexapod as Motion SimulatorHexapod as Motion SimulatorMotion simulators have higher motion dynamics requirements (shakers).
- Parallel Kinematics
- Sensor TechnologiesSensor TechnologiesThe linearity and repeatability achieved are not possible without highest-resolution measuring devices. Accuracies in the range of a few nanometers and below require a position measurement method that can also detect motion in this range.
- Capacitive SensorsCapacitance Nanosensors
- Incremental SensorsLinear Scale Encoders for Nanometrology & Nanopositioning
- PIOne Optical Nanometrology EncoderPIOne Optical Nanometrology Encoder
- Comparison: Position Sensor TechnologiesComparison: Nanopositioning Sensor Technologies
- Capacitive Sensors
- Controllers & SoftwareControllers & SoftwareFast settling or extremely smooth low speed motion, high positional stability, high resolution and high dynamics – the requirements placed on piezo systems vary greatly and need drivers and controllers with a high degree of flexibility.
- Digital & Analog InterfacesDigital & Analog Interfaces
- EtherCAT Connectivity of PI ProductsEtherCAT Connectivity of PI Products
- Control of Piezo ActuatorsPiezo Controllers & Drivers for Nanopositioning Systems
- Digital Motion ControllersDigital Motion Controllers
- SoftwareMotion Control Software from PI
- Active AlignmentActive Alignment
- Digital & Analog Interfaces
- Guiding Systems & Force TransmissionGuiding Systems & Force TransmissionFlexure joints, mechanical guide components or magnetic bearings? Which kind of guiding system PI uses in its products depends on parameters such as travel range, required precision, load, lifetime, and ambient conditions.
- Classical Guiding SystemsComparison: Classical Guiding Systems and Force Transmission
- Flexure Guiding SystemsFlexure Guiding Systems for Nanopositioning & Piezo Actuators
- Magnetic BearingsMagnetic Levitation & Precision Bearings for NanopositioningMagnetic levitation allows excellent guiding accuracy in a plane, both linear and rotational.
- PIglide Air Bearing TechnologyPIglide Air Bearing TechnologyMulti-axis motion with nanometer precision and without friction.
- Classical Guiding Systems
- VacuumPositioning in High Vacuum (HV) and Ultrahigh Vacuum (UHV)Careful handling, adequate premises: PI does not only have the necessary equipment for the qualification of materials, components and final products, but also has many years of experience with regard to HV und UHV positioning systems.
- GlossaryPI Glossary for Technical TermsFind useful explanations of technical terms in the PI Glossary.
- BlogBlogLearn from our experts in the field of motion and positioning, who share their knowledge and their passion for technology.
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Displacement Modes of Piezoelectric Actuators
In addition to the expansion in the direction of polarization, which is utilized with longitudinal actuators, a contraction always occurs in the piezo actuator that is orthogonal to its polarization when it is operated with an electric field parallel to the direction of polarization.
This so-called transverse piezoelectric effect is used by contracting actuators, tube actuators, or bending actuators.
In piezoelectric shear actuators, the electric field in the ceramic layer is applied orthogonally to the direction of polarization and the displacement in the direction of polarization is utilized. The displacements of the individual layers add up in stacked actuators here as well (fig. 2).
The shear deformation coefficients d15 are normally the largest piezoelectric coefficients. When controlled with nominal voltages, the piezo ceramics achieve d15(GS) values of up to 2000 pm/V. The permissible controlling field strength is limited in order to prevent a reversal of the vertically oriented polarization.
When lateral forces act on the actuator, the shear motion is additionally superimposed by a bending. The same effect occurs in dynamic operation near the resonant frequency.
Furthermore, shear stresses cannot be compensated by a mechanical preload. Both limit the practical stacking height of shear stacks. Shear actuators combined with longitudinal actuators yield very compact XYZ stacks with high resonant frequencies.
A typical application for shear actuators are drive elements for stick-slip motors.
Estimation of the displacement of a shear actuator where:
Tube actuators are radially polarized. The electrodes are applied to the outer surfaces, so that the field parallel to the polarization also runs in a radial direction. Tube actuators use the transverse piezoelectric effect to generate displacements. Axial displacements or changes in length (fig. 3), lateral motions such as changes in the radius (fig. 4), as well as bending (fig. 5) are possible.
In order to cause a tube to bend, the outer electrode is segmented into several sections. When the respectively opposite electrodes are driven, the tube bends in a lateral direction.
Undesirable tilting or axial motions that occur during this process can be prevented by more complex electrode arrangements. For example, an eight-electrode arrangement creates a counter bending and overall achieves a lateral displacement without tilting.
Tube actuators are often used in scanning probe microscopes to provide dynamic scanning motions in open-loop operation, and as fiber stretchers. Further application examples are microdosing in the construction of nanoliter pumps or in inkjet printers.
For all tube dimensions, see data sheet >> PT120 – PT140.
ΔLaxial Axial tube displacement [m] ΔLradial Radial tube displacement [m] ΔLlateral Lateral tube displacement [m] d31(GS) Transverse piezoelectric large-signal deformation coefficient [m/V] l Tube length [m] ID Internal tube diameter [m] t Tube wall thickness (=(OD-ID)/2) [m] V Operating voltage [V] GND Ground P Direction of polarization E Electric field strength
Typically, piezo contractors are flat components. Their displacement occurs perpendicularly to the polarization direction and to the electric field. The displacement of contracting actuators is based on the transverse piezoelectric effect whereby up to approx. 20 µm is nominally achieved.
Multilayer elements offer decisive advantages over single-layer piezo elements regarding their technical realization: Due to the larger cross-sectional area, they generate higher forces and can be operated at a lower voltage (Fig. 6).
As a result of the contraction, tensile stresses occur that can cause damage to the brittle piezo ceramic. A preload is therefore recommended.
Estimation of the transverse displacement of a contracting actuator where:
Attached to a substrate, contracting actuators act as bending actuators (fig. 7). For the construction of all-ceramic benders, two active piezoceramic elements are joined and electrically driven. If a passive substrate made of metal or ceramic material, for example, is used, the substrate is referred to as composite bender. The piezoceramic elements can be designed as individual layers or as multilayer elements. Piezoelectric bending actuators function according to the principle of thermostatic bimetals. When a flat piezo contracting actuator is coupled to a substrate, the driving and contraction of the ceramic creates a bending moment, which converts the small transverse change in length into a large bending displacement vertical to the contraction. Depending on the geometry, translation factors of 30 to 40 are attainable, although at the cost of the conversion efficiency and the force generation. With piezoelectric bending actuators, displacements of up to several millimeters can be achieved with response times in the millisecond range. The blocking forces, however, are relatively low. They are typically in the range of millinewtons to a few newtons.
ΔLbend Bending displacement [m] d31(GS) Transverse piezoelectric large-signal deformation coefficient [m/V] n Number of stacked ceramic layers V Operating voltage [V] lf Free bender length [m] hp Height of the piezoceramic element [m] Rh Ratio of substrat height (hs) and piezoceramic element height (hp) in a composite bender (Rh=hs/hp) RE Ratio of the moduli of elasticity of substrate (Es) and piezoceramic element (Ep) in a composite bender (RE=Es/Ep) VF The fixed voltage for bender control [V] (V and VF can be superimposed by an offset voltage) GND Ground P Direction of polarization E Electric field strength
Estimation of the bending displacement of an all-ceramic bending actuator (parallel circuiting) where:
Estimation of the bending displacement of a two-layer composite
bending actuator (one-sided displacement) where: