- 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.
- New ProductsNew Products
- 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 PIMag® Magnetic Direct-Drive Linear MotorStages with PIMag® 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 PIMag® 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
- PIMag® VC Voice Coil Actuators with High Dynamics & Force Control OptionPIMag® VC Voice 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 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 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).
- New Products
- 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
- 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
- OphthalmologyHigh-Precision Drives in Ophthalmic Surgery
- 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
- PIMag® Magnetic Direct DrivesPIMag® Magnetic 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
- 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.
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- About PIAbout PIPI stands for technical excellence and continuous advance in precision positioning – driven by the passion for technology and its use in customer applications. The target of the PI Group is to develop this market and technological leadership even further and therefore secure a decisive competitive advantage for its customers.
- Technology CenterTechnology CenterThe technology center provides space not only for offices but also for application labs, metrology labs, and cleanrooms for vacuum or cryogenic chambers.
- Fractal Manufacturing Structure at PIFractal Manufacturing Structure at PIPI manufactures in autonomous organization fractals. Each unit is responsible for its own product line, has all the necessary skills and production equipment.
- MetrologyMetrologyPI qualifies its products with external measuring equipment. These are calibrated in part and traceable to a national standard. Using the PIOne incremental encoder and capacitive sensors, PI manufactures own metrology for inclusion in PI products.
- Manufacturing in Cleanrooms at PIManufacturing in Cleanrooms at PIPI has the capability to manufacture and qualify products under cleanroom conditions, which is extended and improved continually according to market needs.
- Heavy Load HallHeavy Duty Hall for Positioning Systems Weighing Several TonsThe product range from a two-ton hexapod to a ten-gram nanopositioner requires that PI can both manufacture and qualify these systems. For this reason, PI operates a heavy duty hall at its location in Karlsruhe for the assembly and measurement of masses up to five tons.
- Certified QualityCertified QualityPI aims to apply the same high quality, safety and environmental protection standards worldwide. The Integrated Management System reflects this commitment.
- The PI GroupThe PI GroupPI stands for technical excellence and continuous advance in precision positioning – driven by the passion for technology and its use in customer applications.
- About PI miCosPI miCos GmbH, GermanyAs a member of the PI Group, PI miCos makes a strong contribution in the field engineered systems and is the center of expertise for positioning systems with magnetic drives.
- About ACS Motion ControlAbout ACS Motion ControlACS Motion Control is an OEM-focused supplier of motion controller and drive solutions for high-tech systems in fields such as semiconductor manufacturing, laser processing, additive manufacturing, flat panel display manufacturing, electronic assembly, life sciences, and more. Headquartered in Israel, ACS has technical sales and support offices in the USA, Germany, China, and South Korea. ACS joined the PI Group in January 2017, when PI became a majority shareholder of ACS Motion Control.
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A DC motor with position measurement is called servo motor. The typical characteristics of DC servo motors are uniform, vibration-free operation, a large velocity range, and high torques at low velocity. To benefit in a best possible way from these properties, a motor controller with proportional, integral, and differential control (PID) and suitable filters is required. The servo motor has numerous advantages, such as good dynamics, fast addressing, high torques at low velocities, reduced heat generation, and low vibration.
DC servo motors require an oprating voltage up to 12 VDC. The rotational velocity of the motor is directly proportional to the voltage; the prefix determines the direction. Repeatable positioning requires an additional measuring system.
Brushless DC Motor
PI increasingly uses electronically commuted, brushless DC motors, whereby optimized hollow shaft or torque motors achieve high torques. At the same time, the drive train can be made shorter for the same travel range as the drive shaft is located inside the motor.
ActiveDrive DC Motors
DC motor drives have numerous advantages, including good dynamic performance with a large control range, high torque at low revolutions, low heat dissipation, and low vibration at high position resolution. The cost of a high-performance linear amplifier, however, is generally higher than that for a stepper motor. The ActiveDrive system reduces this cost considerably by integrating a PWM (pulse width modulation) servo amplifier in the motor housing. The operating voltage of normally 24 V for ActiveDrive motors is supplied by a separate power supply included in the scope of delivery. The ActiveDrive concept provides several advantages:
Stepper Motor Drives
Contrary to DC motors, stepper motors only take up discrete positions in a revolution. As these steps have a constant distance, a position may be commanded using the number of steps without any need of a position sensor. Normally, there are 200 to 1000 full steps in each revolution. The actually achievable step width is determined by the stepper motor control, which electronically interpolates up to several hundred thousand microsteps in between the full steps depending on the version PI uses smoothly running 2-phase stepper motors. Stepper motors have a very long service life and, compared to DC motors, are especially suited for applications with reduced dynamics and in a vacuum. A mechanical damper on the motor shaft, which also serves as a handwheel, ensures running smoothness. To maintain a position, stepper motors without self-locking gearhead need to be energized continually. This may cause a position jitter between the steps and generate heat.
System Management Controller Technology for Controlled Stepper Motor Stages
The control technology of the System Management Controller (SMC) stepper motor controls guarantees particularly smooth running of the motors. The result is a very high position resolution, smooth feed, and a large dynamic range of velocity and acceleration. The efficiency of the System Management Controller is very high so that heating of the motors is avoided. System Management Controllers are based on a 32-bit processor with high-resolution amplifiers enabling a position resolution down to the nanometer range. In combination with high-precision mechanical systems, uniform feed velocities of less than 1 μm/s can be achieved. Instead of a linear acceleration profile, a sin2 profile can be chosen so that smooth acceleration and deceleration phases are possible. If stable long-term positioning is required, System Management Controller stepper motor controllers also evaluate position measurement systems and control precisely. Processing of an analog 1 V peak-to-peak value allows setting the position very accurately and infinitely without limitation by bit-depending digital transformation.
System Management Controllers are available in different versions, from a one-channel compact unit to multi-axis control in a 19" housing.
Fig. 1 shows 100 nm steps of a PLS-85 linear stage with two-phase stepper motor without additional position feedback. The stage carries out these steps with great precision. When commanding 25 nm steps (see Fig. 2), there are more variations in the individual steps. On average, these deviations are only ±5 nm.
The position behavior for small steps can be further improved by using a position control, in particular, if the analog output signal of a high-resolution sensor is used for processing. System Management Controllers can process sensor resolutions down to 2 nm, position resolution then only depends on the sensor. However, the environmental effects should not be neglected: variations in ambient temperature of only 0.01 °C already cause thermally induced expansion of the stage by approx. 10 nm. If required, ultra-precision stages or specific developments, such as stages with a granite base and corresponding high-resolution linear encoders, are used.
Fig. 3 shows the measured minimum incremental motion of an LS-110 stage with linear encoder. The 50 nm resolution can be clearly seen with precisely separated steps. Even changes in load do not affect this accuracy.
One decisive parameter for selecting a positioning system is velocity. More often than not this relates to the maximum achievable velocity, but some applications require a particularly slow and even feed motion. This is a major challenge for both stepper motors and DC motors. The velocity control of System Management Controllers guarantees an excellent stability of the stage velocity in the range of << 1 µm/s.
Fig. 4 shows the measuring results of a PLS-85 stage with integrated linear encoder with 10 nm resolution. The velocity was set to 100 nm/s, which equates to a feed of 360 µm/h or approx. 10 mm/d. The motion is very even. The individual steps shown here are due to the interferometer resolution of 5 nm.
The quality of the guides and the drive train normally limits the positioning accuracy that can be achieved. A nonlinearity of the spindle pitch, for example, causes a deviation from the commanded position. In some applications it is important to improve the absolute positioning accuracy while bidirectional repeatability is less relevant. The error correction in the System Management Controller saves the measured deviation and then corrects the target position correspondingly.
Fig. 5 shows the deviation in position of 32 µm between target and actual position of an LS-180 over the travel range of 100 mm. The measurement includes both directions of motion; the average bidirectional repeatability is 1.78 µm.
The result is shown in Fig. 6: the deviation is considerably smaller, only about ±1.5 µm. Repeatability can be improved further by means of position control.
Performance of Stepper Motor AxesOptimization of Precision, Stability, and RepeatabilityWP4004E 2016-06WP4004D 2016-06Whitepaper
Rotating Electric Motors for Precision PositioningAn application-related comparison of different motor typesWP4016 R1 2020-03-25WP4016 R1 2020-03-25