- webserver & intuitive sensor alignment
- targets & materials
- selected measurements
- selected applications
- PTB calibration
With its slim size, the IDS can be directly integrated into machines for free-beam operation and is the product of choice for challenging OEM & synchrotron applications. A passively cooled housing prevents contamination of optical and electrical components. For even more confined applications, sensor heads can be remotely operated and interconnected via glass fibers. Due to an integrated webserver, the sensor can be aligned, initialized and (re-) configured remotely at any time.
A broad spectrum of digital and analog real-time interfaces and protocols enables the simple transmission of position data to the receiver such as CNC controllers or RTOS computers. The further support of the most common industrial networks such as CANopen, Profinet, Profinet RT, EtherCAT, and Biss-C enable the integration into broader industrial and synchrotron networks.
Due to the fast adjustment and precise sub-nanometer resolution of the sensor, we are able to easily identify trajectories and eigen frequencies for the optimization of flexure based components. The combination of the digital interfaces with our motion control system allows most accurate closed-loop control for scanning applications With the closed-loop integration of the IDS3010 in our X-ray microscope by the end of this year, we feel confident to get the first 3-D tomographic pictures of biological samples with a resolution of 20nm within the beginning of 2016.
(DESY/suna-precision GmbH, Hamburg, Germany)
An intense and ongoing scientific exchange with the attocube-development team permitted us to obtain new functionalities and highest precision. Our system, being inherently non-standard, profits greatly from the compactness and modularity of the sensorheads. We rapidly managed to file a patent application implying interferometric metrology.
(Synchrotron Soleil St. Aubin, France)
|number of axes||3|
|working distance||0…5000 mm (depending on sensor head)|
|sensor resolution||1 pm|
|sensor repeatability||2 nm1)|
|max. target velocity||2 m/s|
|measurement bandwidth||10 MHz|
|signal stability (WD: 77 mm)||0.110 nm (2σ)|
|Modes of Operation|
|remote operation||integrated webserver|
|output signal: electronics||sin/cos, AquadB, HSSL, field bus systems (opt.)|
|output signal: displacement measurement||laser light (IR)|
|output signal: alignment laser||laser light (VIS)|
|sensor alignment||via integrated webserver or DLLS|
|sensor initialization||via integrated webserver or DLLS|
|analog interfaces||sin/cos (real-time)|
|digital interfaces||AquadB, HSSL (real-time)|
|field bus interfaces (on request)||EtherCAT, CANopen, Profinet, Profinet RT|
|interface bandwidth BiSS-C||up to 10 MHz (master clock frequency)|
|external master clock||up to 10 MHz|
|clock interferometers axes||independent clock input|
|number of position bits||32 bit|
|chassis||50 x 55 x 195 mm³|
|power supply||12 V DC|
|power consumption||8 W|
|laser source||DFB laser (class 1)|
|laser power||max. 400 µW|
|laser wavelength||1530 nm|
|wavelength stability||50 ppb|
1) at 10 mm working distance in vacuum conditions, +/-1ppm in ambient conditions with ECU.
real-time digital and industrial connectivity
The IDS3010 is delivered with a standard set of high-speed interfaces for real-time data communication with FPGA-based or RTOS receivers. These interfaces consist of an incremental AquadB, a proprietary serial word (HSSL), and a synthetic analog sin/cos signal. All signals can be outputted as either single-ended (LVTTL) or differential (LVDS). Interface parameters can be configured in the web interface section of the IDS.
Alternatively, the IDS can optionally be upgraded with BiSS-C, an open standard sensor interface optimized for multi-device usage. All interfaces provide maximum bandwidth at highest resolution. For OEM customers, interconnectivity with other industrial networks such as Ethernet (TCP/IP), EtherCAT, CanOPEN, Profinet, and Profinet RT can be implemented on request.
HSSL (digital; bandwith up to 25 MHz and 8-48 bit resolution): attocube's proprietary serial word protocol provides absolute position information - both in terms of the protocol and the measurement itself. The HSSL interface consists of one data and one clock signal (single ended or differential); position information is packed into one container of user-defineable bit-length, synchronization with the receiver is accomplished using the clock signal. The HSSL protocol is preferential if absolute displacement position data (i.e. sensor-target separation) is required or if incremental position counting is inacceptable.
|AquadB (digital; bandwith up to 25 MHz; resolution freely assignable): The AquadB interface provides incremental displacement information on target displacement. Position resolution and (maximum) clock rate can be user defined using the software interface. For maximum data bandwidth, the AquadB interface is best used with differential signaling.|
|Sin/cos (analog; bandwith up to 25 MHz; resolution freely assignable, 1pm - 224 pm): The sin/cos signal is a digitally synthesized analog signal which provides incremental position information. As with the digital AquadB signal, the increment (i.e. resolution) is user-definable in the system's web interface. For maximum data bandwidth, the sin/cos signal is best used with differential signaling.
BiSS-C is available as an upgrade option. The sensor interface offers synchronous, real-time-capable data transmission. It provides point-to-point topology for data communication with motion controllers and is especially suitable for the easy integration of several IDS sensors to the master clock at multi device facilities such as synchrotrons and spallation sources. BiSS-C signals are routed through the 14 pin GPIO connector (all other real-time interfaces are disabled in this mode).
Interfaces on request
Other industrial interfaces can be implemented on request. For detailed information, please contact email@example.com
EtherCAT (Ethernet for Control Automation Technology) is an open, real-time Ethernet-based fieldbus network originally developed by Beckhoff. The EtherCAT protocol is most typically used for machine control and regulation as well as for multi-channel, synchronous measurement devices.
|Profinet is a protocol based on industrial Ethernet according to IEEE 802. It connects devices, systems, and cells, facilitating faster, safer, less costly and higher quality manufacturing.
Profinet RT is the real-time derivative of Profinet.
|CANopen is a communication protocol based on CAN (Controller Area Network) which is most typically used for the interconnection of complex, embedded systems used in automation. Apart from communication, the CANopen protocol also provides device specification.|
|target velocity [m/s]||0.00001||0.001||0.01||1||2|
|resolution HSSL (abs.) 8-48 bit, up to 25 MHz [nm]||0.001||0.001||0.001||0.001||0.001|
|resolution AquadB (inc.) at 25 MHz [nm]||0.004||0.04||4||
|resolution Sin/Cos (inc.) at 25 MHz [nm]||0.004||0.04||4||
Integrated Web Server
& Pilot Laser
simple sensor alignment
and remote configuration
All IDS sensors are delivered with an integrated webserver, allowing the end-user to configure and align the device at ease after physical connection with the local area network (LAN). An integrated, software-controllable visible pilot laser greatly simplifies the alignment process (see below). In addition to the intial setup process, the web interface of the IDS further enables the remote upgrade of device specific software/firmware and the readback of absolute position values (sensor-target separation).
Setting up your Measurement
align & initialize your sensor within minutes
Step 1 | Pilot Laser for
The IDS contains a visible pilot laser for coarse adjustment of the target with respect to the sensor head. The pilot laser can be switched on/off at any time.
Step 2 | Signal Strength Indicator
for Fine Alignment
The IDS indicates the actual signal strength via a simple signal bar. This way, the sensor head can be fine aligned within seconds on almost any target – ranging from a 4% reflective glass surface to a 99% reflective mirror or retroreflector.
Step 3 | Initializing the Sensor
After mechanical sensor alignment, the IDS is initialized by pushing a single button in the webinterface. Once initialized, it displays the absolute distance between sensor head(s) and target(s) and is ready to measure any displacement changes from this point on.
Step 4 | Setting Real-time
If any position or displacement data need to be real-time transmitted to an external control unit, there are incremental and absolute position protocols to choose from (optional). Protocol parameters can be preset in the web interface to best fit your needs.
Optical Targets and Materials
measurements down to 4% surface reflectivity
The FPS & IDS sensors are compatible with a variety of targets, target materials, and technical surfaces
(such as drive shafts, end mills etc.). Most frequently, plane mirrors are being used in constrained (uniaxial) or xy-measurement applications (bi-axial).
For long range sensing applications with reduced requiremets on alignment, retroreflectors are most typically used. Depending on sensor head type and sensor-target separation, the alignment tolerances range from 0.1° (glass, single pass) up to several degrees (retroreflectors). Please contact firstname.lastname@example.org for further details.
Proven sub-nanometer signal stability
The intrinsic signal stability of the IDS sensor – equivalent to its positional repeatabilty - is unheard of in industrial position sensing. While being specified to achieve a repeatability of 2 nm at 20 mm working distance and 100Hz measurement bandwidth (in vacuum), IDS sensors routinely achieve significantly better performance. The actual measurement above shows positional stability as measured with an IDS3010 on a titanium cavity cooled to liquid helium temperature (-269 °C), temperature stabilized to few milli-degrees. The plot shows position sensing data recorded on a 77 mm long cavity during a 20 hour period of time, measured at 100 Hz bandwidth. The standard deviation of the above shown measurement is 55 picometer!
Compliant with high-bandwidth & high-velocity applications
Along with exceptional signal stability and picometer resolution, the IDS sensor family is designed to measure target position variations at very high pace. With a measurement bandwidth of 10 MHz, IDS sensors are able to master target displacement velocities of up to 2 m/s. This capability enables applications where objects are moved over macroscopic ranges at high speed while the target’s final location needs to be recorded with nanometer resolution. A typical application is shown in the graph above where the target has been mounted onto a linear drive, providing travel velocities of up to 2 m/s over 1 m range.
Real-time stage guiding accuracy analysis
Monitor your stage guiding accuracy in real time. With an angular tolerance exceeding several degrees, the IDS3010 can sense erratic pitch and yaw motions. A simple closed loop regulation may then control the carrier displacement within 6 degrees of freedom. The IDS3010 cost-effectiveness and compact design allow integration in industrial systems as a set-and-forget sensor. Indeed, interferometry intrinsically eliminates the need for time-consuming system recalibration.
Bearing errors detection with contact-less probe
Characterize the error motions of your bearings. Depending on the probe in use, the IDS3010 tolerates even curved and milled surfaces as target. Therefore, users can monitor the motion at the exact location of interest. For example, it can directly measure the actual runout of a rotating shaft and avoids any in between errors sources such as stage bearing imperfection (Abbe error) or slight angular encoder misalignment.
In-situ live machine vibrometry
Diagnose your parts' vibrations instantaneously. The IDS3010 enables accurate, non-contact frequency analysis with a bandwidth from DC to 10 MHz. Its modular and portable design perfectly fits quality control applications and allow on-the-fly diagnosis of a machine directly in the production line. Moreover, its interface uses industry standards for easy integration.
High velocity & ultra precision motion tracking
Track fast stage displacement with ultimate accuracy. In standard operation, the IDS3010 detects a target's relative displacement over range exceeding 5 m with sub-nanometer resolution. Its real-time electronics outputs linear stage motion with velocities up to 2 m/s. The sensor's compact and ergonomic design eases integration in OEM setups and grants use of this state of the art device even to non-specialists in interferometry.
In-situ live workpiece vibration analysisAnalyse directly your workpiece vibrations. The IDS3010 can recover in-plane motion of a rotating milling machine workpiece. For example, users can measure the difference in vibration spectra arising when the milling process takes place as compared to the idle state. This crucial information enables fine control of the machine tool in order to eliminate contour errors or bad surface finish. This in turn improves part quality and higher production throughput.
Profilometry on Micron-sized Objects
The left figure shows the experimental setup including three sensor heads and a stack of attocube`s positioners and scanners for measuring metallic cylinder. The shown three dimensional color plot on the right side reflects the surface morphology of a 200 μm diameter cylinder. Each color represents a 100 nm height step in z-direction.
Ultra-precise and contactless surface analyses are of major interest in order to guarantee the quality of the material in many research and industrial applications. The large acceptance angle is one of the main strong benefits of attocube’s Industrial Displacement Sensor (IDS). Due to its proprietary patented techniques, the system allows for measurements on surfaces with more than 10° inclination with respect to the measurement direction.
The actual measurement shows nanometer precise 3D profilometry data of micron-sized metal cylinders.Several deformations can be seen: In the center position the object profile clearly shows a dent on its surface with a depth of around 400 nm. In addition the diameter contour in the front part near x = 0 has a plateau over a length of approximately 10 μm.
Measuring Brownian Motion of Commercial Micro-Cantilevers
The shown plot depicts the fast Fourier transform (FFT) analysis between 100 and 400 kHz of a commercial cantilever. The cantilever under investigation has the following dimensions: 225 µm x 38 µm x 7 µm (L x W x T). The resonant frequencies of this cantilever can be seen at 165.6 kHz and the noise floor in the presented frequency range is around 2 pmRMS/sqrt(Hz).
The resolution capability of the IDS was demonstrated by measuring the Brownian motion of micro cantilevers. Measuring the tiny vibrations of objects excited only by its thermal energy is typically challenging the resolution capabilities of a measurement system. The cantilever was placed on attocube positioners and measured with the focusing sensor head (D12/F2.8). This sensor head has a shot diameter of smaller 2 µm. The figure clearly shows an individual resonance peak at 165.6 kHz excited due to Brownian motion.
Figure 1 shows the experimental set-up, figure 2 shows the diagrams of the displacements measured by the IDS after stimulating the optical table: While the optical table oscillates within a range of 2 µm, the maximum amplitude of the water surface is 20 m.
Besides measuring displacements of solid materials, the IDS sensor is also capable of detecting displacements of liquids: the IDS can be used as a water level sensor to detect the displacement of water (and other liquids) levels. This facilitates a broad variety of new applications, e.g. measuring vibrations, analysing hydraulic systems, detecting the liquid level in falling film reactors, or liquid levels in a hydrostatic leveling system.
The following experiment shows the potential of this feature: the IDS was used to measure the one-dimensional displacement in z-axis of an optical table and of the water surface of a cup standing on the optical table. After stimulating the optical table with a light vibration (blow of a hammer), the IDS detected displacements of both the optical table and the water surface (see figure 1 on the left for the experimental setting).
Accuracy of the IDS officially confirmed by PTB
highest accuracy over long distances
The IDS3010 has been tested by the National Metrology Institute of Germany (PTB) over 10 meters with an absolute distance travel range between 1.2 and 11.2 meters. The accuracy of the IDS has been confirmed at various pressure, humidity and temperature conditions over several days, thus also confirming the high performance and reliability of attocube's ECU (environmental compensation unit).
The figure below shows the displacement with an absolute distance offset of 1.2 m, while the y-axis represents the difference between the interferometer of the PTB and the IDS3010. As indicated below, the PTB and the IDS3010 do not show any difference up to a displacement of 3 m.