- 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.
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- 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.
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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.
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- 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.
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- 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
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- 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
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- 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.
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- 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.
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- 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.
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- 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.
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- 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.
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- 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.
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- 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.
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- 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
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- 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.
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- 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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Precision Positioning: Difference between Micropositioning and Nanopositioning
Micropositioning refers to mechanical movements with positioning accuracy and resolution in the micron or sub-micron range. Nanopositioning refers to positioning with nanometer or sub-nanometer resolution.
Design rules for motion systems with millimeter or sub-millimeter resolution do not always apply for the micron and sub-micron range. Resolution in the sub-micron realm cannot always be increased by simple means such as reducing the pitch of a leadscrew or increasing the gear ratio of motor/ gearhead unit. Stiction/friction, play, backlash, wind up effects, tilt, temperature effects, etc. will also limit accuracy and resolution. Sub-micron positioning systems require a great deal of attention in the design, manufacturing and selection of materials.
PI has several decades of experience in designing micropositioning and nanopositioning equipment for a wide range of applications, including piezo flexure nanopositioning systems, air bearing systems, linear, rotation and tilting stages, driven by piezo motors, servo motors, linear motors, rotary motors and stepper motors.Quality Management at PI
PI has been ISO9001 certified since 1994. PI’s capabilities include a state-of-the-art vibration isolated and 0.1 degree temperature controlled sub-nanometer metrology lab to certify the performance of our products. Interferometers, auto collimators and several other ultra-high resolution metrology systems are employed to measure the Guiding and Position Accuracy of our micropositioning and nanopositioning products.
Micropositioning Terms
Definition of Axes and Angles
X: Linear motion in positioning direction
Y: Linear motion perpendicular to positioning direction
Z: Vertical linear motion
θX: Angular motion around X (roll)
θY: Angular motion around Y (pitch)
θZ: Angular motion around Z (yaw)Glossary
Absolute Accuracy
For any given input this is the maximum difference between the commanded (ideal) position and the actual position. Absolute accuracy is often confused with resolution. For real systems, resolution is usually a great deal higher than absolute accuracy which is affected by backlash, hysteresis, drift, linearity, and repeatability. Absolute accuracy in the range of 1 µm or better over more than a few mm of travel, can usually only be achieved with external measuring systems such as laser interferometers or linear glass scales. Leadscrew mounted encoders or stepper motors cannot achieve this kind of accuracy.
Backlash
Lost motion after reversing direction. This can be due to play in screw/nut fittings, gearheads, bearings, etc. Some manufacturers promote controllers with automatic backlash compensation adding the estimated amount of lost motion upon each reversal. A good solution in theory which is limited in practice because backlash varies with load, leadscrew position, temperature, deceleration, direction, wear etc. Backlash can lead to oscillation in closed loop set ups where the position sensor is directly attached to the part to be controlled. Backlash is not to be confused with hysteresis.
Bi-directional repeatability
The accuracy of returning to a position A from any position, regardless of direction. Effects such as hysteresis and backlash affect bi-directional repeatability. See Unidirectional Repeatability.
Cosine Error
A cumulative error that occurs when a drive system is misaligned in regard to the driven part. The error equals 1 – the cosine of the angle between the ideal drive axis and the actual drive axis times the moved distance.
DC Servo Motor
A direct current motor that is operated in a closed loop system (servo circuit). Vibrationless, smooth running, broad speed range and very good low speed torque are characteristics of DC servo motors. For optimum performance a good motor controller with PID (Proportional, Integral, Derivative) filter settings is mandatory.
Guiding Accuracy
See runout
Hysteresis
Hysteresis occurs when reversing direction. Unlike backlash which is lost motion at the beginning of a reversed motion, hysteresis contributes to position error by the relaxation of elastic forces in the drivetrain components. Hysteresis is highly variable based on different load and acceleration values.Micropositioning Terms
Glossary
Design Resolution The theoretical minimum movement that can be made based on the selection of the mechanical drive components (drive screw pitch, gear ratio, angular motor resolution etc.). Design resolution is usually higher than the practical position resolution (minimum incremental motion). Examples where design resolution is higher than position resolution are motor/gear box driven systems with very high gear reduction ratio, or microstepped motors. A linear stage driven by such a motor can require an input of 1,000,000 steps (encoder counts) to move a distance of one mm. In this case one step performed and displayed by the motor controller is equal to 1 nanometer. In reality the stage may not be able to respond to motion input less than 50 steps due to play, windup, friction, backlash etc.
Minimum Incremental Motion
The minimum motion that can be repeatedly executed for a given input, which is sometimes referred to as practical or operational resolution. For systems with microstepped motors or motor / gearbox combinations design resolution and practical resolution have to be distinguished. Design resolutions of 1 nm or better can be achieved with many motor, gearbox and leadscrew combinations. In practical applications, however, stiction/ friction, windup, and elastic deformation limit resolution to fractions of a micron.
Repeatable nanometer or sub-nanometer resolution can only be provided by solid state actuators (PZTs) and PZT flexure stages (see "PZT Flexure NanoPositioners" and "PZT Actuators" sections for details). See also Design Resolution.Orthogonality
The deviation from the ideal 90° angle between the X and Y axis.Precision
An undefined term used differently by different manufacturers. Precision sometimes refers to absolute accuracy, repeatability, even to resolution.Resolution
See Design Resolution and Minimum Incremental Motion. Resolution is often confused with accuracy.Runout (Tracking Accuracy, Guiding Accuracy)
Deviation from a straight line. For linear stages, the runout describes unwanted motion in all 5 degrees of freedom (off-axes) other than the intended linear motion in the commanded direction. For a translation in X, linear runout occurs in Y and Z, tilt occurs in theta X (roll), theta Y (pitch) and theta Z (yaw). Runout is caused by the guiding system itself, by the way the stage is mounted (tension!) and the load conditions.Stepper motor
An electric motor designed for open loop operation providing motion in discrete steps. Stepper motors provide limited dynamic properties compared to DC servo motors of equal size. They also dissipate more heat at steady state operation and produce noise and vibration during motion. Modern, 5 phase designs have mostly overcome these problems. Stepper controller design (open loop) is simple compared to DC servo controller design (closed loop). Stepper motors yield good results in predictable applications.Stick/Slip Effect
Limits resolution. Caused by the fact that the coefficient of static friction is greater than the coefficient of dynamic friction. When a drive force is applied to a positioner the start of motion is out of phase with the build up of force. In the beginning no motion occurs and when a threshold is reached a sudden jump occurs. Only frictionless devices such as solid state actuators (piezo actuators) do not exhibit stiction and therefore provide superior resolution to "classical mechanical positioners" in the sub-micron to sub-nanometer realm.Tracking Accuracy
See runoutUnidirectional Repeatability
The accuracy of returning to a given position from any other position, but always from one direction. Unidirectional repeatability is not affected by backlash. See Bi-directional Repeatability.Guiding Principles and Drive Principles for Motorized Precision Positioning Systems
Magnetic-Kinematic Ball Bearings
Straightness of travel, symmetrical movement and absence of backlash are especially important for precision mechanical positioning.
Magnetically coupled stages use the force of integrated magnets to preload the stage. Although not as good as
Air Bearings and flexure guides, they provide better straightness than is achieved with cross roller bearings.
This magnetic preload results in extremely uniform and smooth motion with minimum friction. To guarantee optimum straightness of travel only one of the two linear bearings guide the stage (V-grooves) while the second bearing only supports (U-grooves) the top platform. Straightness and flatness is better than 0.2 µm over 25 mm. Resolution with the optional PZT drive is better than 10 nm.
Due to the limited magnetic force only small loads can be handled in vertical applications. The same applies to lateral forces.Linear Guiding Rods with Ball Bearings
Precision ground rods of hardened steel and linear ball bearings are used for the M-311 translation stages. A brass tube serves as ball cage. To reduce backlash and guarantee low friction the rods and ball bearings have to be matched with very tight tolerances.
Linear Rails with Double Row Recirculating Ball Bearings
Several types of motorized translation stages are equipped with precision double linear rails. The moving carriage is supported by a total of four preloaded linear bearings with two rows of recirculating balls each. The rails are bolted to the precision machined stage base by several screws. Precision assembly allows these bearings to yield excellent results in terms of straightness, smoothness and load capacity.
Leadscrews
A drive system consisting of a screw and a nut coupled to the carrier. Leadscrews are self-locking but exhibit higher friction (motor output power, max. velocity) than recirculating ballscrews. M-125, and M-400 stages are equipped with leadscrews. Standard PI leadscrews have a pitch of 0.5 mm/revolution.
Recirculating Ballscrews
Recirculating ballscrews reduce the sliding friction of leadscrews to rolling friction. They consist of a screw, a nut (ball housing) and a number of balls riding between the screw and the nut. When the screw rotates, the revolving balls transmit an axial movement to the housing attached to the carriage. Before the balls reach the end of the thread they recirculate to their original position through a channel in the housing. By selecting a certain ratio of ball diameter and thread diameter a backlash eliminating preload is generated.
Ballscrews show significantly reduced friction, wear and longer lifetime than leadscrews. They reach higher velocities than leadscrews with efficiencies up to 90 %. Ballscrews are not self-locking. M-500 stages are equipped with recirculating ball-screws. Standard PI ball-screws have pitches of 1 and 2 mm/revolution.
Almost any PI translation or rotation stage is available with a motor drive. Three different drives are available:DC Motor Direct Drives
Advantages of DC motor direct drives are high speed, acceleration and absence of vibration. Low heat dissipation at rest and fast response (ideal for tracking and contouring applications) are further advantages.
Standard shaft mounted optical encoders provide resolution down to then anometer range. Highest positioning accuracy is achieved with integrated linear encoders.
DC Motor/Gearhead Drive
Advantages of DC motor/gearhead drives are very high angular resolution and low power consumption (can be operated by PC controller boards without external amplifier). 3 Watt DC motors with gearheads and motor shaft mounted encoders are used. Encoders provide 2000 and 60 counts/revolution, respectively. Zero backlash motor/gearhead combinations are available for improved repeatability.
5 Phase Stepper Motor Drives
High resolution 5-phase stepper motors with 2000 steps/rev. are used. Low vibration, high angular stiffness and exceptional angular accuracy are the benefits of 5-phase stepper motors. These factors provide considerable advantages over conventional 2/4-phase stepper motors, which must use electronic micro stepping techniques (with several disadvantages) to achieve comparable resolution. Compared to DC servo motors stepper motors are especially suited in applications where predictable point to point positioning is required rather than fast response and extreme acceleration.
DC-Mike Motorized Micrometer Drive Options
These micrometer replacement actuators have non rotating tip constructions driven by a 2 Watt DC servo motor/ gearhead with motor shaft mounted encoder. The units are used on some of our translation and rotation stages and feature sub-micron resolution.
PZT Piezoelectric Drive Options
Resolution on the order of 1 nm and better can be achieved with piezo actuators. Drive options are available for several of our translation and rotation stages. Piezo translators can move very fast and do not exhibit stiction/friction or backlash. See "PZT Actuators" for further information.
This is a legacy product that may have limited availability or may have been replaced. Ask a PI engineer for an equivalent new model.
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