- OEM / SystemsOEM Systems | Precision Components | Automation Sub-SystemsPI offers 1000’s of proven, off-the-shelf precision motion products that can be quickly modified for the OEM or into a custom automation sub-system.
- Meeting the Demands of OEMsOEM Systems | Precision Components | Automation Sub-SystemsPI has a long track record of working with OEMs in the most demanding industries from Semiconductor Technology to Medical Design – industries where product performance, quality, and the ability to ramp up quickly are not the only parameters required to satisfy the customer's demands. Working with technology leaders all around the world forces you to continuously improve your yield, process, and product performance. And unless your quality is outstanding, you cannot become a key supplier to major US, European, and Japanese companies in the Optics, Photonics, Semiconductor, and Automotive industry.
- Engineered Motion / Automation Sub-SystemsPrecision Automation Solutions | Engineered SystemsPI is a supplier of high-end precision motion systems and makes use of own drive components and high-precision positioners to build customized positioning and automation sub-systems —“motion engines”—for our customers. With the largest portfolio of precision motion technologies in the industry, PI engineers have the best foundation to find a solution that matches your requirements in terms of precision, quality and budget – in a timeframe that works for you.
- Meeting the Demands of OEMs
- ProductsPrecision Motion Technologies | Positioning SystemsOverview of the Broadest & Deepest Portfolio of Precision Motion and Automation Technologies from Piezo to Air Bearings and Linear Motors
- Products: Overview, New, Finder, ShopFind Precision Positioning Solutions Quickly - Product Finder | PI USAWith thousands of standard products and customization available, PI has the motion control positioning product solution for your application.
- Products OverviewProducts OverviewOverview of the Broadest & Deepest Portfolio of Precision Motion and Automation Technologies from Piezo to Air Bearings and Linear Motors
- New ProductsNew Motion Control & Precision Positioning Products | PI USALearn about the latest innovations in motion control and nanopositioning components and systems.
- Product FinderUse the PI Product Finder - it's fast and easy!Select 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 at time, for example, to find positioning stages designed for higher load capacity, too.
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- Air Bearings & Ultra High Precision StagesAir Bearing Stages | Motorized | Linear | RotaryAir bearings provide advantages over mechanical bearings when vibration-free motion is required, highly constant velocity control is crucial, and when angular repeatability and geometric performance must be optimal. Air bearing stages (linear, rotary, and spherical) replace mechanical contact by a thin air film, avoiding wear, friction, vibration, and hysteresis effects.
- Miniature Positioning StagesMiniature Positioning Stages | Supplier | ManufacturerCompact positioning stages are crucial for the miniaturization process in cutting-edge research and industrial applications, for test & measurement, optical and opto-mechanical alignment, and component assembly. PI provides the largest portfolio of miniature stages, including high-speed linear motor stages, economical stepper motor units, and ultra-compact piezo motor positioners.
- Motorized Stages: Linear, Rotary, XYMotorized Stages | Positioning | ManufacturerPI offers the broadest and deepest range of precision motion technologies for micro and nano precision applications. Our engineers work with our customers to find the best drive and bearing technology for each individual application. Having access to multiple drive and positioning technologies allows an open discussion with a better outcome for the customer.
- Overview - Motorized Linear/Rotary StagesOverview - Motorized Linear/Rotary Stages
- Linear StagesLinear Stages - Precision Positioning Solutions | PI USASeveral types of motorized precision linear translation stages | PI USA
- Fast Linear Motor Stages and ActuatorsOverview: Linear Stage, Linear Motor Driven, Fast Brushless Motor Positioning Stages | PI USABrushless linear motor-driven stages provide high speed, precision and long life.
- Z-Stages (Vertical Motion)Vertical Linear Stages – Precision Motorized Z-Positioners | PI USA
- XY StagesXY Stages – 2-Axis Motorized Precision Positioning Stages | PI USASeveral types of planar XY stages: Direct-driven stages, ball-screw stages and air bearing planar XY stages
- XYZ StagesXYZ Stage - Multi-Axis Precision Motorized Stages
- Rotary Stages / GoniometersPrecision Rotation Stage, High Resolution Rotary Positioners, Rotation Tables, Goniometers, by PI USASeveral types of motorized rotation stages: Direct-driven stages, ball-bearing stages and air bearing stages
- Heavy Duty Stages / Industrial AutomationHigh Speed / Performance Positioning Stages for Automation - Linear Stages | Rotary Stages | PI USAHigh performance motorized stages, designed for heavy duty applications in industrial precison automation.
- Sub-Systems for AutomationSYS > Engineered Motion/Automation Sub-SystemsThe PI group employs over 1,200 people in 15 countries and runs engineering and manufacturing centers on 3 continents. Select from the broadest portfolio of precision motion technologies, including piezoelectric and air bearing systems, with 1,000’s of standard products or have our engineers provide you with a custom solution.
- Overview - Motorized Linear/Rotary Stages
- Linear ActuatorsActuators | Precision | Linear | Actuator SystemA precision linear actuator is a positioning device that provides motion in 1 degree of freedom. PI designs and manufactures a variety of precision linear actuators (pushers) including economical stepper-motor driven actuators, high-speed linear motor types for automation and nanometer precise piezo-motor actuators.
- Gantries / Cartesian RobotsGantry Stages | Gantries | Cartesian RobotA gantry precision positioning stage is sometimes called a linear robot or Cartesian robot. Gantries typically provide motion in 2 or 3 linear degrees of freedom (X-Y and X-Y-Z) and are often used for pick and place applications, 3D printing or laser machining, and welding applications.
- 6-Axis Hexapods / Parallel PositionersHexapod Positioner | Six DOF | Stewart PlatformsHexapod positioners are often referred to as Stewart Platforms. A hexapod is based on a 6-axis (XYZ, Pitch, Roll, Yaw) actuator system arranged in parallel between a top and bottom platform. PI parallel kinematics (PKM) precision positioning systems have many advantages over serial kinematics stages, such as lower inertia, improved dynamics, smaller package size and higher stiffness. In addition hexapods are more flexible than conventional 6 axis positioners.
- 6-Axis Hexapods / Parallel Positioners6-Axis Hexapods / Parallel Positioners
- Control of Hexapod / Stewart Platforms: Hexapod Motion Controllers & Simulation Software6DOF Motion Platforms | Hexapod Controllers & Simulation Software | Stewart Platform | ManufacturerControllers, software and accessories for Hexapod Stewart platforms and parallel kinematic motion systems | PI USA
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- Piezo Flexure Nanopositioning StagesNanometer Precision: Piezo Stages for Nanopositioning, Piezo Nanopositioners, Piezo Flexure Scanning Stages | PI USAPI offers the broadest and deepest portfolio of nanometer precision motion technologies, from piezo-driven nanopositioning and scanning stages to motorized 6-axis hexapod positioning systems.
- Overview - Piezo Flexure StagesOverview - Piezo Flexure Stages
- Linear Piezo Flexure StagesLinear Piezo Stages for Nanopositioning – Flexure-Guided Precision NanoPositioners | PI USALargest selection of frictionless, high performance piezo-stack-driven flexure linear nanopositioning stages | PI USA
- Vertical & Tip/Tilt Piezo StagesPiezo Z-Stage, Piezo Z-Tip-Tilt Platform. Flexure Guided Nanopositioning Stages| PI USALarge selection of Piezo Z-Stages and Tip/Tilt scanners with nanometer precision | PI USA
- Fast Steering Mirrors & Tip/Tilt PlatformsPiezo Steering Mirrors | Active Optics
- Nanofocus Lens ScannersFast Piezo Focus Lens Positioners and Scanners – Piezo Flexure Guided Precision Positioners | PI USALargest Selection of Nano-Focus drives for microscope lenses – flexure-guided precision positioners
- XY Piezo Flexure StagesPiezo Stages | XY | Nanopositioning StagesLargest selection of integrated XY piezo flexure stages with nanometer precision.
- XYZ Piezo Flexure StagesXYZ Piezo Nanopositioning Stages – Flexure Guided 3-Axis Precision Positioners | PI USALargest selection of integrated XYZ piezo flexure stages with nanometer precision.
- 6-Axis Piezo Flexure Stages6-Axis Piezo Nanopositioning Stages – Flexure Guided Precision Positioners | PI USAPiezo-driven fast steering mirrors (FSM) achieve nanoradian resolution and high bandwidth.
- Tutorial - Piezo NanopositioningNanometer Precision: Nanopositioning Basics Tutorial. Piezo Nanopositioners, Scanning Stages, Flexure Guided Positioners | PI USAThere are several ways to achieve nanometer precision motion. The best positioning systems avoid friction all together, in both the drive system (motor) and in the guiding system (bearings). Frictionless bearings also avoid the bearing rumble caused by balls and rollers and provide vibration-free motion with highly constant velocity.
- Overview - Piezo Flexure Stages
- Piezo Motors: Stages & ActuatorsPiezo Motors | Linear Motor Positioners | ManufacturerPiezo Motors are intrinsically vacuum compatible, non-magnetic and self locking at rest, providing long travel compared to traditional piezo mechanisms. The individual drive concepts are optimized for different applications, they differ in their design, size, cost, force & speed and other performance parameters.
- Overview - Piezo Motors (Stages/Actuators)Overview - Piezo Motors (Stages/Actuators)
- Actuators with Piezo MotorsCompact precision linear actuators stages with several types of piezo motor drives – ultrasonic, stick-slip, piezo-walk, piezo-ratchet. | PI USA
- Linear Stages with Piezo MotorsPrecision linear stages with several types of piezo motor drives – ultrasonic, stick-slip, piezo-walk, piezo-ratchet. | PI USA
- XY Stages with Piezo MotorsXY piezo motor linear stages with several types of precision piezo motor drives – ultrasonic, stick-slip, piezo-walk | PI USA
- XY Piezo Flexure StagesXY Piezo Flexure StagesHigh-precision 2-axis nanopositioning systems integrate PICMA® piezo actuators for maximum reliability. Repeatable, drift-free positioning with optimal stability is possible by the use of high-quality nanometrology sensors.
- Rotary Stages with Piezo MotorsRotary piezo motor stages with several types of precision piezo motors– ultrasonic, stick-slip (inertia), | PI USA
- Tutorial - Piezo Motion ControlWhy All Piezo Motors are NOT Created Equal: The piezoelectric effect for precision motion control - PI Physik Instrumente.The demand for higher speed and/or precision in fields such as bio-nanotechnology, semiconductors, metrology, data comm, and photonics keep pushing manufacturers to come up with innovative drive technologies.
- Overview - Piezo Motors (Stages/Actuators)
- Piezo Transducers & ActuatorsPiezo Actuator | Piezo Transducer | ManufacturerPiezoelectric translators (transducers) are precision ceramic actuators which convert electrical energy directly into linear motion with high speed, force and virtually unlimited resolution. These actuators are used in every modern high tech field from semiconductor test & inspection to super-resolution microscopy, bio-nanotechnology and astronomy/aerospace technology.
- Piezo Actuators & Transducers: Stacks, Chips, Benders, Tubes, Spheres, Shear…Piezo Actuators & Transducers: Stacks, Chips, Benders, Tubes, Spheres, Shear…
- Value-Added Piezo Transducers & Piezo AssembliesValue Added Piezo Assemblies: Transducers, Actuators, Sensors, Manufactured by PI CeramicDeveloping and manufacturing piezo ceramic materials and components are complex processes. PI Ceramic - PI’s piezo material design and manufacturing facility - boasts several decades of experience as well as the right tools for rapid prototyping of custom engineered piezo components and assemblies. From the formulation of advanced piezo materials to the processing steps such as cutting, milling, grinding, and the precision assembly, every stage is controlled by our engineers and product specialists.
- Piezo Ceramic ComponentsPiezo Ceramic Components
- Piezo Actuators & Transducers: Stacks, Chips, Benders, Tubes, Spheres, Shear…
- Microscopy, Bio-Imaging, Life SciencesHigh Precision Microscope Stages, Piezo Lens Scanners, Tools for Bio-Imaging | PI-USAPiezo nano-positioning stages are essential tools for high-resolution microscopy, such as Super Resolution Microscopy or AFM. Their sub-atomic resolution and extremely fast response allow researchers to create higher-quality images faster. PI provides a large variety of fast Z-Stages and collar piezo objective positioners for 3D imaging (Z-stack acquisition), deconvolution, and fast focusing applications.
- Stages for Microscopy & Bio-ImagingStages for Microscopy & Bio-Imaging
- Applications: Life Sciences / MedicalPrecision motion control for medical engineering and life sciences applications | PI USA
- Stages for Microscopy & Bio-Imaging
- Photonics Alignment SolutionsActive Photonics Alignment | Optics Alignment | SolutionsPI provides a variety of innovative fiber alignment systems from motorized fiber positioners to automated optic and photonic alignment such as used in telecommunication, data commumication and for packaging / automation. In addition to fiber-based applications, fast steering systems for free-space-optical communication are also available. Products range from motorized 6D micromotion alignment systems for industrial photonics automation, through ultra-fast piezoelectric scanning & alignment modules to modular devices with manual control for laboratory test setups. All motorized systems come with extensive software for easy setup and integration.
- Vacuum Positioning Stages & ActuatorsVacuum / UHV Compatible Stages - Linear & Rotary Positioners for Vacuum, Wide Temperature Ranges | PI USAPI miCos has extensive experience in the design and manufacturing of vacuum and high vacuum compatible precision optomechanical positioning equipment for low temperature and wide temperature ranges. We provide translation stages, vertical linear stages, rotation stages, XY stages and complex multi-axis positioning systems in vacuum spec.
- 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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- Controllers, Drivers, Motion SoftwareMotion Controllers, Piezo Drivers-High Voltage Amplifiers, and Motion Software Overview | PI USA
- Overview - Controllers & Motion SoftwareOverview - Controllers & Motion Software
- Piezo Controller, Driver, Nanopositioning Controller, High-Voltage Amplifier, Piezo Power Supply by PI USAPiezo Drivers | Piezo Motion Controllers | ManufacturerA piezo controller or driver is used to control the motion of a piezo positioning device. There are open and closed loop controllers. Open-loop controllers are often referred to as piezo driver or even piezo power supply. Closed-loop controllers are divided in two basic types: analog-servo and digital servo controllers.
- Controllers/Drivers for Motorized StagesMotion Controller | Drivers | Positioning SystemsPI provides a large variety of hardware & software solutions for high precision motion control. Our portfolio spans from integrated compact single axis servo controllers / drivers, such as popular Mercury-class motion controllers, to complex multi-axis systems for parallel-kinematics positioners, such as hexapods.
- ACS Motion ControlACS Motion Control for Industrial AutomationWe recommend the controllers of our partner, ACS Motion Control especially for automation with industrial standards. Ask us about your integrated solution!
- Software - Motion Control SoftwareMotion Control Software | Software Tools | Positioning SolutionsFor LabView, C++, VB, Matlab, Image Acquisitiong Packages, NI DAC Cards, ..... PI provides high-level, robust, easy-to-use software tools for fast, seamless integration of motion systems into application control software.
- Overview - Controllers & Motion Software
- Capacitive SensorsNanometer Resolution: Capacitance Sensors for Nano-Measuring, Nano-Metrology | PIA capacitive sensor is a proximity sensor that detects nearby objects by their effect on the electrical field created by the sensor.
- Accessories: Plates, Brackets, CablesAdapters and Cables for PI Precision Motion ComponentsStandardization is common with adapter plates and brackets, but we can create a custom accessory to fit your application system. PI products ship with the required cables. Customization is always an option.
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- Tech BlogPI Blog / Tech Articles on Advancements in Precision Motion Control, Automation and Piezo Technology | PI USAPI’s tech blog offers 50 years of insight into innovative applications of precision motion control, nanopositioning, and micropositioning in industry, science, and research. We hope the PI blog is an enjoyable and informative resource, and a starting-point for innovation across disciplines.
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Drives such as voice coil, linear, or torque motors are electromagnetic direct drives. In direct drives, the force of the drive element is transmitted directly to the load to be moved (e.g., to a linear or rotary table, without mechanical transmission elements such as coupling, drive screw, or gearhead). Electromagnetic direct drives consist of a winding body (coil) in which a magnetic field is formed when current runs through it and a carrier or magnet assembly on which the magnets are mounted.
The force or torque for the acceleration of the load is generated by the Lorentz force. This force is proportional to the magnetic field strength and the current passing through the current-carrying conductor. The electrical energy is converted here into mechanical energy. The generated force acts bidirectionally depending on the direction of the current. In principle, either the winding body (“moving coil”) or the magnet assembly (“moving magnet”) can be moved. The moving part is referred to as the secondary part, the static part as the primary part.
PI has many standard and customer-specific positioning solutions on offer that are equipped with magnetic direct drives; the company has also many years of experience in the design, construction, and manufacture of the necessary system components such as guides, sensors, control technology, and software. PI can also develop proprietary magnetic motors if positioning systems need to achieve specific performance characteristics that cannot be reached by using drive components currently available on the market, for example, to achieve a high force density or a compact design. These proprietary motors, developed in-house, are identified by the PIMag® brand name and positioning systems using these PI motors are identified by the Driven by PIMag® logo.
Voice coil drives are single phase motors consisting of a permanent magnet and a winding body that are located in the air gap of the magnetic field. When current flows through the winding body, it moves in the magnetic field of the permanent magnet. Particularly compact dimensions can be achieved when rectangular or flat shapes are built.
Cylindrical voice coils are constructed according to the plunger coil principle (i.e., the coil sits in a field assembly). Either the winding body or the field assembly can be moved. With the so-called multi-coil principle, the motor constant of cylindrical voice coil motors can be optimized in compact installation spaces and even solutions with hollow shafts can be realized, for example. Voice coil drives are suitable for scanning applications that require high precision, high dynamics, and high velocities at travel ranges up to ten millimeters.
Voice coils can also be optimized for force or motor constant. The motor constant denotes the ratio of force to power loss. The higher the motor constant, the less heat is produced when a certain force is generated. It describes the efficiency of the motor in regard to converting electrical into kinetic energy. As the temperature rises, the winding resistance and, therefore, also the power loss increase, which is why the motor constant is temperature-dependent.
The force depends on the position since the coils move in relation to the permanent magnets along the travel range. In order to drive the force into the motor as quickly as possible, the voltage can be increased since the current is then made available correspondingly faster. The acceleration increases in the same ratio. Highly dynamic applications are, therefore, possible through a fast increase in acceleration (jerk). Cylindrical motors are used, for example, in positioning solutions for focusing tasks in order to dynamically move a measuring head or an optical system vertically, or in endoscopes.
Linear Motors
A classical 3-phase linear motor is basically a series of at least three (or a multiple of three) voice coil motors. The individual coils can be controlled according to a position-dependent, fixed pattern (i.e., commutated). Linear motors are used both for very high and for very low feed velocities. They work precisely in a range from below 0.1 µm/s to more than 5 m/s. If combined with air or magnetic bearings, a position resolution down to a few nanometers is possible.
Optionally, under vacuum, PI can apply a special epoxy resin to its linear motors. This results in an improved heat dissipation, whereby higher nominal forces can be achieved. In addition, the sealing compound ensures that the motor is encapsulated and therefore protected against external damage (e.g., during assembly). For applications that require high velocities or fast current rise times, PI can design motors for very high operating voltages of up to 600 VDC.
The magnetic tracks used in PI linear motors are available in various lengths, they can be connected in series in order to realize any desired travel range. Single-sided or U-shaped magnetic tracks are available.
U-shaped magnetic tracks achieve higher magnetic field strengths and thus higher forces than single-sided magnetic tracks. If the magnets are additionally arranged as a Halbach array, the magnetic field strength can be increased by about 10% compared to a North Pole to South Pole arrangement. In addition, the iron counterplate can be omitted in a Halbach array, making these magnetic tracks significantly lighter. The advantages of using a Halbach array also apply to single-sided magnetic tracks. In this case, the use of Halbach arrays minimizes stray fields on the rear side. PI offers carbon supports for applications that require ultra-light magnetic tracks.In iron-core motors, the core of the coil unit consists of iron. The iron maximizes the magnetic forces and contributes to a high force density and a high thermal stability. To reduce eddy current losses, the iron is laminated and it is mostly made of stacked and insulated transformer plates.
The iron in the coil unit causes attraction forces between the coil unit and the magnet assembly, leading to the occurrence of cogging and therefore to a fluctuation of the feed force over the travel range. Specially designed marginal teeth optimize the cogging. Iron-core linear motors are suitable for applications requiring high forces and accelerations while having a limited installation space.The winding body of ironless linear motors does not have an iron core. This means that there are no attracting forces between the coil and the magnet assembly and cogging does not occur. The lack of an iron core also reduces the weight of the motor itself. Since there is no cogging that affects the guides and feed velocity, and the winding body is lighter, ironless motors are characterized by high travel accuracy, high velocity stability, and high accelerations. Power and dynamics requirements can be met by increasing the number or the dimension of the motor coils. In most cases, ironless motors achieve lower nominal and peak forces than iron-core motors. This is due to the lack of thermally conductive metals in the design and the resulting limited heat dissipation from the coils. The motors are, therefore, protected against overload by means of temperature sensors.
Ironless linear motors are suitable for applications requiring high dynamics in a compact installation space, while having the highest demands on precision.In principle, a torque motor is a linear motor that is arranged radially. The stator of the torque motor contains coils and is firmly mounted; the rotor contains the magnet assembly. While the magnet length scales linearly, the torque scales quadratically with the diameter. Therefore, large torques are generated on a large diameter. In addition, large radial dimensions make it possible to create apertures for the passage of laser beams or cables.
Because of the direct drive principle, torque motors are backlash free. The zero-play allows high positioning accuracy and high drive rigidity, resulting in high repeatability. The high drive torque enables high acceleration and therefore high dynamics. Additional features include high torsional rigidity, high peak torques, high degrees of efficiency, as well as very smooth running.
Among others, torque motors are suitable for high load rotation stages on single or multi-axis assemblies thanks to their compact design with respect to torque and rotational symmetry.
Position, Velocity, and Force Control
Because they are current-controlled, with the driving force being linearly dependent on the current, magnetic direct drives cannot only be operated based on position or velocity control, but also force control.
The force control allows operation with a defined holding or feed force. The force and position sensors can be read individually or simultaneously in a double control loop. In addition to pure force control, subordinate position and velocity control is also an option. The auto-zero function defines the holding current at which the drive produces a force of 0 N during open-loop operation.Weight Force Compensation
Magnetic direct drives installed vertically must hold both the motion platform and the load of the application against gravity. This is possible thanks to weight force compensation. It is adapted to the load and keeps the components to be moved in position even without motor forces. This allows the motor force to be used exclusively for the positioning task. The weight force can be compensated magnetically, pneumatically, or mechanically. PI uses different methods depending on the required performance characteristics.
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