- 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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- 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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- 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
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- 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
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- 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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- 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.
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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.
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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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Electrical Requirements for Piezo Operation
General When operated far below the resonant frequency a Piezo behaves as a capacitor where displacement is proportional to charge (first order estimation).
Piezo stack actuators are assembled with thin wafers of electroactive ceramic material electrically connected in parallel.
Design of a Piezo stack actuator. The (small signal) capacitance of a stack actuator can be estimated by
C ≈ n*ε0*ε33*A/ds (4-14)
Where
n = number of layersε0 = dielectric constant in vacuum [As/Vm]
ε33 = relative dielectric constant [without Dimensions]
A = electrode surface area [m²]
ds = distance between the individual electrodes (layer-thickness) [m]
The above equation shows that for a given actuator length l0 and a given disk thickness d0 capacitance is a quadratic function of the ratio d0 / d1 where d1 < d0. Therefore, the capacitance of a piezo actuator constructed of 100 µm thick layers is 100 times the capacitance of an actuator with 1 mm thick layers if the two actuators are the same length.
Static Operation
When electrically charged, the energy E = 1/2 CU2 is stored in a piezo actuator. Every change in the charge (and therefore in the displacement) of the Piezo requires a current i:i= dQ/dt = C * (dU/dt) (4-15)
Relationship of current and voltage for the piezo actuator
Where
i = current [A]
Q = charge [Coulomb; As]
C = capacitance [Farad; As/V]
U = voltage [V]
t = time [s]
For static operation only the leakage current has to be supplied. The high internal resistance reduces leakage currents to micro-amp or sub-micro-amp range. Even when disconnected from the electrical source, the charged actuator will not make a sudden move but return to its uncharged Dimensionss very slowly (> 1 hour).
For slow position changes, very low current is required. For example an amplifier with an output current of 20 µA fully expands a 20 nF actuator within one second.
Low Voltage PZTs (100 µm layers, 100 V operating voltage, high capacitance) require 10 times the driving current of High Voltage PZTs of similar size (1 mm layers, 1000 V operating voltage, low capacitance). Power requirements are similar. PI High/Low Voltage amplifiers are specially designed to meet the different requirements for driving High/Low Voltage actuators.
Dynamic Operation (Analog)
PZTs can provide accelerations of thousands of g's and are perfectly suited for dynamic applications.Several parameters influence the dynamics of a Piezo positioning system:
Mechanical considerations:
- If the piezo element is installed in a positioning mechanism (and sufficient electrical power from the amplifier is available), the maximum drive frequency can be limited by dynamic forces.
- The maximum operating frequency is also limited by the phase and amplitude response of the system (especially in closed loop systems). Rule of thumb: the higher the system resonant frequency the better the phase and amplitude response and the higher the usable frequency.
Electrical considerations:
- The amplifier output current and rise time determine the maximum operating frequency of a piezoelectric system.
- In closed loop operation other parameters such as sensor bandwidth, phase margins and control algorithms determine the performance of a positioning system.
The following equations describe the relationship between amplifier output current, voltage and operating frequency. They help determine the minimum specifications of a Piezo amplifier for dynamic operation.
iA ≈ f * C * Up-p (4-16)
Average current required for sinusoidal operation
imax ≈ f * p * C * Up-p (4-17)
Peak current required for sinusoidal operation
fmax ≈ imax/(2 * C * Up-p) (4-18)
Maximum operating frequency with triangular ave form as a function of the amplifier output current limit
Where
iA = average amplifier source/sink current [A]
imax = peak amplifier source/sink current [A]
fmax = maximum operating frequency [Hz]
C = Piezo actuator capacitance [Farad (As/V)]
Up-p = peak-peak drive voltage [V]
f = operating frequency [Hz]
The average current and maximum current for each PI Piezo amplifier can be found in the technical data.
Example:
Q: What peak current is required to operate a HVPZT actuator with a nominal displacement of 40 µm @ 1000 V and capacitance of 40 nF with a sinusoidal wave form of 1000 Hz at 20 mm displacement?
A: With a nominal displacement of 40 mm @ 1000 volts, approximately 500 Vp-p are required to expand the actuator by 20 mm. With equation 4-17 the peak current is calculated to be » 63 mA. (Matching amplifiers can be found in the "Piezo Control Electronics" section of this catalog).
The following equations describe the relationship between (reactive) drive power, actuator capacitance, operating frequency and drive voltage.
The average power a piezo driver has to be able to provide for sinusoidal operation is
Pa ≈ C * Umax * Up-p * f (4-19)
Peak power for sinusoidal operation is:
Pmax ≈ p * C * Umax * Up-p * f (4-20)
Where
Pa = average power [W]
Pmax = peak power [W]
C = Piezo actuator capacitance [Farad (As/V)]
f = operating frequency [Hz]
Up-p = peak-peak drive voltage [V]
Umax = maximum output voltage swing of the amplifier [V]
The Piezo capacitance values indicated in the technical data tables are small signal values (measured at 1 V, 1000 Hz, 20° C, no load). The capacitance of Piezo ceramics changes with amplitude, temperature, and load, up to 200% of the unloaded, small signal capacitance at room temperature. For detailed information on power requirements, refer to the amplifier frequency response graphs in the "Piezo Control Electronics" section of this catalog.Instead of calculating the required drive power for a given application, it is easier to calculate the drive current because it grows linearly with both frequency and voltage (displacement). Output current capability for all PI High Voltage and Low Voltage amplifiers is given in the technical data tables (section "Piezo Control Electronics").
If you have any questions, ask a PI engineer for help.
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