Motion Tracking for Mechanical Load Tests of Gear Boxesand Drive Power-Trains
The components in drive engineering industries need to be tested for numerous mechanical characteristics, e.g. gear boxes need to be checked for long-term smoothness, synchronization, backlash, torsional stiffness, tribological behavior, and/or mechanical resilience. WITTENSTEIN alpha develops and produces mechanical and mechatronic servo drive systems for applications that require maximum precision. The testing facilities of WITTENSTEIN are fitted with vertical, linear motion gearbox test benches.
Since the integrated glass scale is limited in measurement accuracy and bandwidth, WITTENSTEIN uses attocube´s fiber-based interferometer IDS3010, which provides picometer resolution and up to 10 MHz real-time data output. Furthermore, the laser based measurement and the miniaturized components allow to measure as close as possible to the point of interest, without influencing the setups behavior. This enables test and development engineers to determine mechanical and tribological phenomena that could not be detected using conventional glass scales.
This measurement was realized with the Displacement Measuring Interferometer.
High resolution FMCW Radar System
Several industrial progresses, e.g. security or automotive applications, require reliable and high-resolution distance measurements. The group of Nils Pohl at the Fraunhofer Institute for High Frequency Physics and Radar Techniques (Wachtberg, D) and Ruhr-University Bochum (Bochum, D) presented now a fully integrated silicon-germanium based frequency-modulated continuous-wave radar sensor working at 224 GHz with a tuning frequency of 52 GHz. By correcting systematic errors, the outstanding accuracy of the measurement system between -3.9 to +2.8 µm is demonstrated using attocube's laser interferometer FPS1010, a former version of the IDS3010. This high accuracy recommends the radar sensor for multiple applications where radar sensors were not usable before.
This measurement was realized with the Displacement Measuring Interferometer.
Deformation Detection of Satellite Flight Instruments
The space environment imposes extremely stringent design constrains on observation spacecrafts, especially in terms of thermo-elastic stability, leading to the use of advanced materials and thermal architectures. These constrains also translate into demanding validation processes including accurate characterizations and thermo-mechanical models correlations by means of ambient and high vacuum test campaigns.
OHB system AG used attocube’s interferometric displacement sensor, IDS3010, for an opto-thermo-mechanical model correlation test in high vacuum for the Meteosat Third Generation (MTG) Flexible Combined Imager instrument.
The test consisted in injecting controlled thermal fluxes in different zones of the instrument and monitor its subsequent optical elements relative displacements measured with a Shack-Hartmann sensor. With the precise measurement of the IDS3010 the stability of the relative position of a flat reference mirror and the IRS instrument was continuously monitored with an accuracy of less than 1 arcsecond during the whole duration of the test which lasted more than a week in vacuum in total.
This measurement was realized with the Displacement Measuring Interferometer.
Fiber based laser interferometry stimulating the development of highly precise micro manufacturing
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.
This measurement was realized with the Displacement Measuring Interferometer.
Ultra-precise contactless detection of bearing errors
To monitor the health status of a gear or machine, attocube’s IDS3010 can be used to track machine vibrations. To improve the vibration behavior of a machine, its motor was rotated at different speed levels and the motor’s vibrations were measured on the outer shell of the motor. Conducting a live Fast-Fourier-Transformation (FFT) showed that the motor rotating with 2000 rpm generated vibrations at 270 Hz which in turn amplified a system resonance at 345 Hz, and therefore drastically increased the overall vibration amplitude. At this system status, the vibrations amplitude was identified to be more than 150 nm, while the maximum acceptable amplitude was set to 100 nm. This crucial information enabled the system’s manufacturer to minimize the system response to vibrations and prevented potential failure.
This measurement was realized with the Displacement Measuring Interferometer.
Optical Interferometer in Quality Control of a Nanopositioner
We've combined two of our products to ensure the highest quality delivered to our customers: In this application note we show the implementation of the FPS3010 interferometer in the quality control process of our nano drives. The outstanding precision of the FPSensor will ensure that every positioner delivered fulfills the highest quality standards, whereas the easy & robust alignment of the sensor permits high throughput, and therefore reduced lead-time.
This measurement was realized with the Displacement Measuring Interferometer.
Detecting vibration propagation and parasitic motions with picometer resolution
Exact sample positioning in synchrotron beamlines requires position detection with highest resolution. A group at the Diamond Light Source designed a sample positioning system with three positioners for x, y, z movements. To determine the error motions, eight axes of three IDS3010 devices were triggered for synchronous data acquisition, controlling the movement with BiSS-C interface. They identified parasitic motions of only 100 pm that were caused in the non orthogonal fixing of the positioners. These smallest amount of deviation can be detected in Ultra-high vacuum only - and with the IDS3010.
(Trevor Bates, Brian Nutter, Diamond Light Source Limited, Oxfordshire, England)
This measurement was realized with the ECSx5050/Al/RT, and the Displacement Measuring Interferometer.
The SpaceDrive Project - The IDS3010 to gauge a thrust balance in the sub-µN range
Interstellar travel is one of mankind's biggest dream. An ongoing and so far unanswered challenge is the search for an engine, capable of accelerating a rocket to a velocity, which allows us to reach the next star within a lifetime. The basic concept is that for the acceleration no huge trust is necessary as long as it can be supplied continuously throughout the whole travel. A key element of the quest is a propellantless engine, in other words, one that is not based on a momentum generated by ejecting some material, the propellant.
The two currently most researched ideas are the EMDrive and the Mach-Effect Thruster. So far there is no convincing experiment that proves or disproves either concept. A crucial element of this research is a tool to measure extremely small forces (the thrust generated by an experimental sized engine) in a perfectly isolated environment, where all other effects can be eliminated.
The Group of Maxime Monette is developing one such setup by putting a ultra-precise torsion pendulum into a large vacuum chamber and measuring its movement with pm resolution using attocube's IDS3010 interferometric displacement sensor, as shown on the picture. Thanks to their clever design and the pm resolution of the IDS3010 they were able to achieve sub-Nanometer resolution in a UHV environment without introducing any electronic or mechanical noise.
This measurement was realized with the Displacement Measuring Interferometer.
Further reading:
Martin Tajmar et al; SP2018_016
OEM Interferometers for motion tracking in coordinate measurement machines
Coordinate measurement machines (CMM) have highest requirements towards precision. CMM determine geometrical dimensions of simple and complex products and components for quality control (e.g., measurements of manufacturing accuracy or tribological measurements). Those applications require an accuracy in a sub-micrometer range, while the calibration and the machine-integrated control need a higher level of accuracy.
The laser interferometers of attocube are solutions providing highest precision and large working distances at the same time - suiting the challenging requirements of CMM. While the IDS3010 allows to measure displacements of up to 5 meters, it simultaneously detects overshoots in the nanometer range. Furthermore, the compact design of the IDS3010 and the sensor heads fits machine-integrated applications.
Customers can choose:
- target velocity up to 2m/s
- direct beam or mirror deflection
- Workings distances of up to 5 meters with a constant precision in nanometer range
- In situ measurements on the touching probe without Abbe errors instead of mechanically transmitted position acquisition (e.g glass-scales)
- Compact interferometer unit for machine-integration
This measurement was realized with the Displacement Measuring Interferometer, and the .
Ultra Precise In-Line Travel Property Control
In many industrial processes, motion and accuracy of motion are of utmost importance. This is true for machining processes (e.g. ultra-precision machining), wafer processing and inspection, metrology measurements, and many other applications.
For this purpose, attocube has designed a three-axis miniature laser interferometer, which provides ultra precise real-time measurement of linear target motion as well as analysis of parasitic pitch and yaw motions. If embedded in a closed loop circuitry, motion in three degrees of freedom can be controlled down to the nanometer scale.
Customers can choose:
- sensor head diameter from 1 mm up to 15.5.mm
- distance sensor head to target from 0 mm to > 1 meters
- target velocity up to 2 m/s
- direct beam or mirror deflection
- customized housing
This measurement was realized with the Displacement Measuring Interferometer, and the .
Machine Integrated Sensors for Motion Capturing
The growing demand for high accuracy position sensing in machine tools requests cost efficient yet flexible sensors with high resolution at potentially large working ranges. Up to today, interferometry has been well known for highest accuracy but also high costs and demanding space requirements, making it unattractive for mass application and machine integration.
attocube's IDS3010 now solves this challenge: the ultra compact OEM interferometer is an economic solution and optimized for machine integration with unrivaled optical performance. Especially for applications exceeding the specifications of industry-wide used glass-scales, the IDS3010 is capable of capturing motions more accurate than other measurement systems.
Customers can choose:
- a wide range of interfaces (analog sin/cos, digital incremental, field busses)- various sensor head designs for environments ranging from low temperature to 400°C. sensor head diameter from 1 mm up to 15.5 mm
- distance sensor head to target from 0 mm to > 5 meters
- target velocity up to 2 m/s
- direct beam or mirror deflection
- customized housing
This measurement was realized with the Displacement Measuring Interferometer, and the .
Long distance and high-speed displacement measurements
Machine vibrations induce errors in parts manufacturing. The miniscule vibrations of a milling machine produce erratic motions of the workpiece with regards to the cutter and hence, may lead to contouring errors or a bad surface finish. Such defective parts create problems and can jeopardize the whole system’s assembly or safe operation. In the end, they may fail quality criterions such as the 6-σ standard. Get our latest application note & see how the FPS3010 can help to efficiently and precisely characterize vibrations, thus helping to succesfully eliminate these errors.
This measurement was realized with the Displacement Measuring Interferometer.
Position Capturing in Coordinate Measurement Machines
Cordinate measurement machines (CMM) measure more than just distances, they are capable of capturing a broad range of geometries: angles, profile of a surface, parallelism, symmetries, tolerances, circularity, and much more. For those applications, CMM provide an accuracy in a sub-micrometer range. To enable this level of accuracy, CMM need even more accurate sensors to be calibrated.
Since glass-scales do not measure the displacements of the touch probe itself, they cannot detect the actual overshoots and motion of the touch probe. Because of the contactless measurement technology, attocube’s IDS (Industrial Displacement Sensor) is capable of focusing on the touch probe directly and capturing the motions at the point of interest.
This measurement was realized with the Displacement Measuring Interferometer.
Environmental Compensation
Any interferometric device operated in environmental conditions is negatively influenced by index of refraction fluctuations, caused by air temperature, pressure, and humidity variation. The influence of these parameters is significant and can reach deviations in measurement of up to 500 ppm, equivalent to a deviation of 500 µm per meter.
To compensate these errors, attocube offers an environmental compensation unit (ECU) which precisely measures environmental parameters and determines the actual index of refraction n(t). This measurement allows to compensate environmental influences down to better 1 ppm and enables highly precise, accurate measurements in air.
(attocube application labs, 2017)
This measurement was realized with the Displacement Measuring Interferometer.