- Products ProductsPI 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 Finder Product 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 Products Customized 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 Stages Nanopositioning Piezo Flexure StagesPI's piezo flexure stages combine sub-nanometer resolution and guiding precision with minimum crosstalk.
- Multi-Axis Piezo Flexure Stages Multi-Axis Piezo Flexure Stages
- PIFOC® Objective & PInano® Sample Scanners for Microscopy PIFOC® Objective & PInano® Sample Scanners for Microscopy
- Linear Piezo Flexure Stages Linear Piezo Flexure Stages
- XY Piezo Flexure Stages XY Piezo Flexure Stages
- XYZ Piezo Flexure Scanners XYZ Piezo Flexure Scanners3-Axis Nanopositioning Scanners of Maximum Precision
- Piezo Flexure Tilting Mirrors Piezo Flexure Tilting Mirrors
- Multi-Axis Piezo Flexure Stages
- Miniature Stages Miniature 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 Stages Miniature Linear Stages
- Miniature Rotation Stages Miniature Rotation Stages
- Miniature Hexapods Miniature Hexapods
- Miniature Linear Stages
- Linear Stages Linear 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 PIMag® Magnetic Direct-Drive Linear Motor Stages with PIMag® Magnetic Direct-Drive Linear Motor
- Stages with Stepper, DC & Brushless DC (BLDC) Motors Stages with Stepper, DC & Brushless DC (BLDC) Motors
- Vertical Stages with Stepper, DC & Brushless DC (BLDC) Motors Vertical Stages with Stepper, DC & Brushless DC (BLDC) Motors
- Miniature Linear Stages Miniature Linear Stages
- Stages with PIMag® Magnetic Direct-Drive Linear Motor
- Linear Actuators Linear 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 Stability PiezoMike for Long-Term Stability
- Linear Actuators with Stepper & DC Servo Motors Linear Actuators with Stepper & DC Servo Motors
- PIMag® VC Voice Coil Actuators with High Dynamics & Force Control Option PIMag® VC Voice Coil Actuators with High Dynamics & Force Control Option
- PiezoMove Lever Actuators PiezoMove Lever Actuators
- Nanopositioning Piezo Actuators Nanopositioning Piezo Actuators
- PiezoWalk® Actuators with High Force & Stability PiezoWalk® Actuators with High Force & Stability
- PIRest Active Piezo Shims PIRest Active Piezo Shims
- PiezoMike for Long-Term Stability
- Rotation Stages Rotation 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 Stages XY 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.
- Hexapods HexapodsHexapods provide 6 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 Automation Engineered 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 Alignment Fast 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 Software Motion Control SoftwareAll digital controllers made by PI are accompanied by an extensive software package.
- Concepts Concepts
- User Programs and Their Functions User Programs and Their Functions
- Software Tools for Hexapods Software Tools for Hexapods
- Programming Programming
- Third Party Support Third Party Support
- Controllers & Drivers Controllers & 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 Controllers Nanopositioning Piezo Controllers
- Piezo Drivers for Open-Loop Operation of Piezo Actuators Piezo Drivers for Open-Loop Operation of Piezo Actuators
- Motion Controllers & Drivers for Linear, Torque, Stepper & DC Servo Motors Motion Controllers & Drivers for Linear, Torque, Stepper & DC Servo Motors
- Controllers & Drivers for Piezomotors Controllers & Drivers for Piezomotors
- Controller Systems for Multiple Axes & Mixed Drive Types Controller Systems for Multiple Axes & Mixed Drive Types
- Hexapod Motion Controllers Hexapod Motion Controllers
- Nanopositioning Piezo Controllers
- Piezoelectric Transducers & Actuators Piezoelectric 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 Cylinders Piezoceramic Discs, Rods & Cylinders
- Plates and Blocks Piezoceramic Plates & Blocks
- Rings Piezoceramic Rings
- Tubes Piezoceramic Tubes
- Spheres and Hemispheres Piezoceramic Spheres & Hemispheres
- Bending Elements Piezoceramic Bending Elements
- Tube Actuators Piezo Tube Actuators
- PICMA® Piezo Linear Actuators PICMA® Piezo Linear Actuators
- PICMA® Piezo Bender Actuators PICMA® Piezo Bender Actuators
- PICA Piezoelectric Stack Actuators PICA Piezoelectric Stack Actuators
- PICA Shear Actuators PICA Shear Actuators
- DuraAct Piezoelectric Transducers DuraAct Piezoelectric Transducers
- Picoactuator® Piezoelectric Crystal Picoactuator® Piezoelectric Crystal
- Discs, Rods and Cylinders
- Air Bearings & Stages Air 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 & Accessories Sensors, Components & Accessories
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- OEM OEMCustomer- 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 Robots Hexapods Support Industrial Robots
- Scientific Instrumentation Scientific Instrumentation
- Hexapod Systems for ALMA Hexapod Systems for ALMA
- Double-Crystal Monochromator Double-Crystal Monochromator for an X-Ray Spectrometer
- Materials Research in High Vacuum Materials Research in High Vacuum
- Active Vibration Isolation with Piezo Actuators Active Vibration Isolation with Piezo Actuators
- Drive Technology for the ELT Drive Technology for the ELT
- Hexapod Systems for ALMA
- Semiconductor Technology Semiconductor Technology
- Microscopy Microscopy
- Confocal Microscopy Adjustment 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 Microscopy High-Speed Microscopy for Quality Control
- Atomic Force Microscopy AFM Scanner for Atomic Force Microscopy
- White Light Interferometry 3-D Surface Inspection With Piezo-Based Positioning Systems from PI
- Confocal Microscopy
- Silicon Photonics Silicon Photonics
- Photonics Packaging Automated Photonics Packaging
- Optical Fiber Alignment Simultaneous Testing of Optical Components in Silicon Photonics
- Photonics Packaging
- Medical Technology Medical Technology
- Endoscopy Chip-on-the-Tip Video Endoscopes with Miniature Drives
- Ophthalmology High-Precision Drives in Ophthalmic Surgery
- Magnetic Resonance Imaging Nonsensitive Drives for Magnetic Resonance Tomography
- Optical Coherence Tomography Piezo Technology and Optical Coherence Tomography (OCT)
- Pipetting Piezomotors for Pipetting and Nanodispensing
- Precision Dosing Dynamic Drives for Precision Dosing with Nanodispensers
- Micropumps Piezoelectric Micropumps – Compact Design and High Performance
- Image Stabilization Image Stabilization and Microscanning with Piezo Scanners
- Adaptive Diaphragm Positioning Adaptive Diaphragm Positioning
- Materials Research Materials Research
- Parallel Kinematics for Materials Research High-Load Parallel Kinematics for Materials Research
- Laser Beam Control Piezo Drives for Laser Beam Control
- Parallel Kinematics for Materials Research
- Mechanical Engineering Mechanical Engineering
- Electrical Discharge Machining Piezo Actuators Accelerate Electrical Discharge Machining
- Hexapods in Mechanical Engineering Hexapods in Mechanical Engineering
- Electrical Discharge Machining
- Automation Automation
- Smarter Motion Positioning Smarter Motion Positioning
- Hexapods in Microproduction Hexapods in Microproduction
- Hexapods for Quality Assurance Hexapods for Quality Assurance
- Magnetic Direct Drives Magnetic Direct Drives
- Motion Simulation with Hexapods Motion Simulation with Hexapods
- Flexibility in Dimensional Measuring Hexapod Systems in Automation
- Motion Compensation with Hexapods Motion Compensation with HexapodsDynamic hexapods with piezo drives: Best conditions for motion compensation.
- Fast Piezo Ultrasonic Drives Advance Technology Fast Piezo Ultrasonic Drives Advance Technology
- Laser Material Processing Laser Material Processing
- Hexapods for Optical Metrology Hexapods Support Precise Measurement of Aspheres
- Smarter Motion Positioning
- Beamline Instrumentation Beamline Instrumentation
- Tomography Equipment Tomography Equipment
- Synchrotron Spectroscopy in Vacuum Synchrotron Spectroscopy in Vacuum
- Beam Preparation Beam Preparation
- Sample Positioning for Tomography Sample Positioning for Tomography
- Microscopy Microscopy
- Accelerator Technology Accelerator Technology
- Tomography Equipment
- Vacuum Vacuum Compatible Linear & Rotary Stages, UHV Positioners
- Additive Manufacturing Additive Manufacturing
- TechnologyKnow-How & TechnologyPhysik Instrumente (PI) provides several linear motor techologies, e.g., ironless linear motors for applications requiring high dynamics and accuracy.
- Piezo Technology Piezo 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 Technology Fundamentals of Piezo TechnologyPhysical basics and explanations of piezo electricity and electromechanics.
- Properties of Piezo Actuators Properties of Piezo Actuators
- Piezoceramic Materials Piezoceramic MaterialsPI Ceramic offers a variety of different piezoelectric materials including lead-free materials.
- Manufacturing Technology Manufacturing Technology
- PICMA® Technology PICMA® Technology
- Integrated Piezo Actuators Integrated Piezo Actuators
- DuraAct Patch Transducer Technology DuraAct Patch Transducer Technology
- PIRest Actuators PIRest ActuatorsActive shims with long-term stability and nanometer resolution.
- Fundamentals of Piezo Technology
- Piezoelectric Drives Piezoelectric 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 Actuators Piezo Actuators with and without Guiding
- PiezoWalk® Walking Drives PiezoWalk® Walking Drives
- PILine® Ultrasonic Piezomotors PILine® Ultrasonic Piezomotors
- Piezo Inertia Drives Piezo Inertia Drives
- PiezoMike Linear Actuators PiezoMike Linear Actuators
- Comparison: Piezo Motors & Drive Technologies Comparison: Piezo Motors & Drive Technologies
- Piezo Actuators
- Electromagnetic Drives Electromagnetic 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 Motors Rotating Electric Motors from PI
- PIMag® Magnetic Direct Drives PIMag® Magnetic Direct Drives
- PIMag® 6-D Magnetic Levitation PIMag® 6-D Magnetic Levitation at Six Levels of Freedom
- Hybrid Concept Piezo & Motor Hybrid Concept
- Rotating Electric Motors
- Parallel Kinematics Parallel 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 Kinematics Piezo Positioning Systems with Parallel KinematicsIn a parallel-kinematic, multi-axis system, all actuators act directly on a single moving platform.
- Multi-Axis Positioners Multi-Axis Positioners and Stewart Platforms
- Hexapod as Motion Simulator Hexapod as Motion SimulatorMotion simulators have higher motion dynamics requirements (shakers).
- Parallel Kinematics
- Sensor Technologies Sensor 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 Sensors Capacitance Nanosensors
- Incremental Sensors Linear Scale Encoders for Nanometrology & Nanopositioning
- PIOne Optical Nanometrology Encoder PIOne Optical Nanometrology Encoder
- Comparison: Position Sensor Technologies Comparison: Nanopositioning Sensor Technologies
- Capacitive Sensors
- Controllers & Software Controllers & 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 Interfaces Digital & Analog Interfaces
- EtherCAT Connectivity of PI Products EtherCAT Connectivity of PI Products
- Control of Piezo Actuators Piezo Controllers & Drivers for Nanopositioning Systems
- Digital Motion Controllers Digital Motion Controllers
- Active Alignment Active Alignment
- Digital & Analog Interfaces
- Guiding Systems & Force Transmission Guiding 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 Systems Comparison: Classical Guiding Systems and Force Transmission
- Flexure Guiding Systems Flexure Guiding Systems for Nanopositioning & Piezo Actuators
- Magnetic Bearings Magnetic Levitation & Precision Bearings for NanopositioningMagnetic levitation allows excellent guiding accuracy in a plane, both linear and rotational.
- PIglide Air Bearing Technology PIglide Air Bearing TechnologyMulti-axis motion with nanometer precision and without friction.
- Classical Guiding Systems
- Vacuum Vacuum Compatible Linear & Rotary Stages, UHV PositionersCareful 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.
- Glossary PI Glossary for Technical TermsFind useful explanations of technical terms in the PI Glossary.
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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: