Development of a metrological reference system for the form measurement of aspheres and freeform surfaces based on a tilted-wave interferometer

Abstract Aspheres and freeform surfaces play an important role in today's optics industry. However, the measurement of such complex surfaces is still challenging even with state-of-the-art manufacturing technology, and there is an urgent need in industry for a non-contact, highly accurate reference measurement technique. To meet this demand, at PTB, a metrological reference system for the contact-free form measurement of aspheres and freeform surfaces is under development. The measurement system is based on a tilted-wave interferometer. Advances in computational capabilities have made it possible to solve the complex inverse problems associated with this measurement system and to develop sophisticated analysis procedures for reconstructing the surface under test from the measured interferogram data. In this paper, we will present the status of the tilted-wave interferometer-based measurement system at PTB, describe the analysis procedures we have designed and show initial measurement results. The benefit of the implementation presented here is that it allows insight to be gained into the performance of the measurement system and enables traceable measurements to be established with low uncertainty.

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Multi-Probe Measurement System Based on Single-Cut Transformation for Fast Testing of Linear Arrays

Sensors ◽

10.3390/s21051744 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1744

Author(s):

Fernando Rodríguez Varela ◽

Manuel José López Morales ◽

Rubén Tena Sánchez ◽

Alfonso Tomás Muriel Barrado ◽

Elena de la Fuente González ◽

...

Keyword(s):

Measurement System ◽

Near Field ◽

Linear Measurement ◽

Complete Characterization ◽

Linear Arrays ◽

Full Characterization ◽

X Band ◽

Measurement Results ◽

The Many ◽

3D Information

This paper introduces a near-field measurement system concept for the fast testing of linear arrays suited for mass production scenarios where a high number of nominally identical antennas needs to be measured. The proposed system can compute the radiation pattern, directivity and gain on the array plane, as well as the array complex feeding coefficients in a matter of seconds. The concept is based on a multi-probe antenna array arranged in a line which measures the near field of the antenna under test in its array plane. This linear measurement is postprocessed with state-of-the-art single-cut transformation techniques. To compensate the lack of full 3D information, a previous complete characterization of a “Gold Antenna” is performed. This antenna is nominally identical to the many ones that will be measured with the proposed system. Therefore, the data extracted from this full characterization can be used to complement the postprocessing steps of the single-cut measurements. An X-band 16-probe demonstrator of the proposed system is implemented and introduced in this paper, explaining all the details of its architecture and operation steps. Finally, some measurement results are given to compare the developed demonstrator with traditional anechoic measurements, and show the potential capabilities of the proposed concept to perform fast and reliable measurements.

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Kontaktkräfte beim ungeführten Vibrationsgleitschleifen*/Contact forces in unguided vibratory finishing

wt Werkstattstechnik online ◽

10.37544/1436-4980-2015-06-29 ◽

2015 ◽

Vol 105 (06) ◽

pp. 377-383

Author(s):

F. Klocke ◽

R. Brocker ◽

F. Vits ◽

P. Mattfeld

Keyword(s):

Measurement System ◽

Electrical Power ◽

Force Sensor ◽

Contact Forces ◽

Work Piece ◽

Data Logging ◽

Vibratory Finishing ◽

Revolution Speed ◽

Measurement Results ◽

Finishing Processes

Beim Vibrationsgleitschleifen wird der Werkstoffabtrag maßgeblich durch die vorherrschenden Kontaktkräfte zwischen dem Werkstück und den Schleifkörpern bestimmt. Dieser Fachartikel stellt ein Messsystem vor, mit dem die messtechnische Erfassung der Kontaktkräfte beim ungeführten Vibrationsgleitschleifen möglich ist. Ein Alleinstellungsmerkmal ist dabei die vollständig kabellose Ausführung des Messsystems. Somit wurden die Messergebnisse nicht durch Kabel beeinflusst, die üblicherweise für die Energieversorgung und Datenübertragung notwendig sind. Mithilfe dieses Messsystems wurde der Einfluss folgender Prozesseingangsgrößen systematisch untersucht: Schleifkörpergröße, Unwuchtmotordrehzahl, Versatzwinkel der Unwuchtgewichte sowie die Masse des unteren und oberen Unwuchtgewichts auf die Kontaktkräfte.   In vibratory finishing the material removal is influenced by the contact forces between work piece and media. In this paper a measurement system is presented which is able to measure contact forces between work piece and media in unguided vibratory finishing. The unique feature of the measurement system is its completely wireless construction so that the measurement results are not influenced by wires of the force sensor system including the electrical power supply and the data logging. By means of this measurement system, contact forces can be measured in unguided vibratory finishing processes for the first time. Furthermore, the influence of media size and adjustment of the unbalance motor like revolution speed, phase angle and mass distribution between the upper and the lower eccentric weight on the contact forces was investigated.

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The problem of credibility studies on deformations of engineering objects in the geologically unstable area of Szczecin

E3S Web of Conferences ◽

10.1051/e3sconf/20187100018 ◽

2018 ◽

Vol 71 ◽

pp. 00018

Author(s):

Marek Zygmunt ◽

Stefan Cacoń ◽

Andrzej Piotrowski ◽

Grzegorz Stępień

Keyword(s):

Measurement System ◽

Geological Structure ◽

Reference Points ◽

Test Method ◽

Geological Conditions ◽

Measurement Results ◽

Basic Issue ◽

Class 1 ◽

Proper Diagnosis ◽

Control And Measurement System

The location of reference points in deformation studies of engineering objects is often associated with low reliability of the obtained measurement results. This concerns the lack of proper diagnosis of the geological structure of the area. The reliability of deformation measurements is also low when we obtain data that only characterize the effects and not the cause-and-effects. The authors reviewed the influence of geological conditions on the formation of deformations of some engineering objects. The reference points were located in the immediate vicinity of the facilities, without taking into account the geological structure of the areas where the facilities were located. The proposed test method is based on a three-segment control and measurement system. An example of such considerations is the engineering facilities on the Grodzka and Ostrów Grabowski Island in the Szczecin area. The basic issue is to locate geologically stable areas in the vicinity of monitored engineering objects on the basis of geological substrate assessment and to analyse archival materials concerning periodical measurements of class 1 and 2 levelling lines in the Szczecin area. Reference points are located, which constitute the first segment of the control and measurement system. Subsequent segments of the system are organized with reference to the points of the first segment. This method provides reliable data on deformations of engineering objects.

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The Noise Source Localization of Industrial Sewing Machine by NAH Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.300-301.898 ◽

2013 ◽

Vol 300-301 ◽

pp. 898-902 ◽

Cited By ~ 1

Author(s):

Zhi Wei Li ◽

Tao Feng ◽

Zhi Gang Huang ◽

Bin Su ◽

Ran Li ◽

...

Keyword(s):

Source Localization ◽

Measurement System ◽

Theoretical Basis ◽

Noise Source ◽

Near Field ◽

Sound Intensity ◽

Front Surface ◽

Acoustic Holography ◽

Sewing Machine ◽

Measurement Results

According to the Near-Field Acoustic Holography (NAH) theory, we designed a measurement system, which was used to localize the noise source on five hologram surfaces of a industrial sewing machine. Moreover, we compared the localization results of the noise source on the front surface of the industrial sewing machine by NAH and sound intensity method respectively. The measurement results can provide a theoretical basis for controlling the noise of industrial sewing machine.

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An Optical-Triangulation-Based Method for Measurement of Blade Sections

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.713-715.395 ◽

2015 ◽

Vol 713-715 ◽

pp. 395-401

Author(s):

Yong Zhu ◽

Jing Liang Liu ◽

Cheng Wei Li ◽

Zheng Ya Kang

Keyword(s):

High Efficiency ◽

Optical Measurement ◽

Measurement Methods ◽

Free Form ◽

Probe Radius ◽

Optical Triangulation ◽

Measurement Results ◽

Probe Radius Compensation ◽

Free Form Surface ◽

Radius Compensation

Blades are an important part of aviation engine, its manufacturing compliance seriously affect the performance of the engine. Blades tend to be free-form surface modeling, which makes it extremely difficult to measurement. Since no probe radius compensation, high efficiency, non-contact optical measurement methods get more and more attention, but the inspection uncertainty of optical measurement is usually between 30um to 50um .To reduces the optical non-contact measurement uncertainty, this paper presents an Optical-triangulation-based method for measurement of blade sections. There is a data optimization process in the method, and this feature makes the proposed method can obtain better measurement results. At last, some experiments demonstrate the effectiveness of this method.

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Rotating Coil Magnetic Measurement System and Measurement Results of Quadrupole Prototype for BEPCII Storage Ring

Proceedings of the 2005 Particle Accelerator Conference ◽

10.1109/pac.2005.1590932 ◽

2006 ◽

Cited By ~ 1

Author(s):

Li Li ◽

Ying-Jie Li ◽

Gan-Lin Ni ◽

Wan Chen ◽

Xian-Jing Sun

Keyword(s):

Storage Ring ◽

Measurement System ◽

Magnetic Measurement ◽

Measurement Results

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Design of Intelligent Resistivity Measurement System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.705.204 ◽

2014 ◽

Vol 705 ◽

pp. 204-207

Author(s):

Shu Fen Qi ◽

Kun Zhang

Keyword(s):

Measurement System ◽

Resistivity Measurement ◽

Drilling Mud ◽

Single Chip ◽

Single Chip Microcomputer ◽

Control Center ◽

Real Time Measurement ◽

Drilling Parameters ◽

Measurement Results ◽

Reliable Basis

Accurate measurement of the drilling mud resistivity is very important to analysis of drilling parameters. Therefore, it is necessary to produce an accurate measurement system. The resistivity measurement system which is introduced in this paper adopts STM8s single chip microcomputer as the control center. It sends control commands via I2C technology and completes the measurement of resistivity using AD5933. Then data is sent to the MCU. When the MCU deals with the data, LCD screen displays measurement results. The system has so many advantages: low power, portable, real-time measurement etc. It provides a reliable basis for analyzing the parameters of drilling.

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DEVELOPMENT OF THE HIGH FIELD MAGNETO-OPTICAL MEASUREMENT SYSTEM WITH A ROTATIONAL CAVITY FOR THE STUDY OF ORGANIC CONDUCTORS

International Journal of Modern Physics B ◽

10.1142/s0217979204027487 ◽

2004 ◽

Vol 18 (27n29) ◽

pp. 3803-3806 ◽

Cited By ~ 2

Author(s):

M. KIMATA ◽

H. OHTA ◽

K. KOYAMA ◽

Y. OSHIMA ◽

M. MOTOKAWA ◽

...

Keyword(s):

Measurement System ◽

High Field ◽

Optical Measurement ◽

Superconducting Magnet ◽

Organic Conductors ◽

Network Analyzer ◽

Fermi Surfaces ◽

Optical Measurement System ◽

Measurement Results ◽

New System

We have developed a new magneto-optical measurement system with a rotational cavity. It consists of a millimeter vector network analyzer and a 15T solenoid type superconducting magnet and it can go down to 1.5 K. The rotational cavity can be used in the transmission configuration and the rotation can be performed up to almost 360 degrees in 1 degree precision. We will show the magneto-optical measurement results of β"-(BEDT-TTF)(TCNQ) using our new system. We observe the quasi-two-dimensional periodic orbit resonance (POR) in β"-(BEDT-TTF) (TCNQ). The Fermi surfaces of this system will be discussed.

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Planar Offset Short Applicable to the Calibration of a Free-Space Material Measurement System in W-Band

Journal of Electromagnetic Engineering and Science ◽

10.26866/jees.2021.21.1.51 ◽

2021 ◽

Vol 21 (1) ◽

pp. 51-59

Author(s):

Jin-Seob Kang ◽

Jeong-Hwan Kim

Keyword(s):

Electrical Properties ◽

Measurement System ◽

Free Space ◽

Physical Contact ◽

Frequency Range ◽

Electromagnetic Devices ◽

W Band ◽

Measurement Results ◽

Properties Of Materials ◽

Space Material

The electrical properties of materials and their dependence on frequency and temperature are indispensable in designing electromagnetic devices and systems in various areas of engineering and science for both basic and applied researches. A free-space transmission/reflection method measuring the free-space scattering parameters of a material under test (MUT) located at the middle of transmit/receive antennas in a free space is suitable for non-destructively testing the MUT without prior machining or physical contact in high-frequency range. This paper describes a planar offset short applicable to the calibration of a quasi-optic based free-space material measurement system in the millimeter-wave frequency range. The measurement results of the dimensional and electrical properties for the three fabricated planar offset shorts with the phase difference of 120° between the reflection coefficients of the planar shorts in the W-band (75–110 GHz) are presented.

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PENETAPAN SISTEM ACUAN DAYA AC UNTUK LABORATORIUM STANDAR NASIONAL BERDASARKAN STANDARD WATT CONVERTER

Jurnal Standardisasi ◽

10.31153/js.v17i1.287 ◽

2016 ◽

Vol 17 (1) ◽

pp. 11

Author(s):

Agah Faisal

Keyword(s):

Measurement System ◽

Reference System ◽

Digital Voltmeter ◽

National Standard ◽

National Metrology Institute ◽

Standard Laboratory ◽

Reference Measurement ◽

Power Meter ◽

Ac Power ◽

Reference Measurement System

Abstrak Puslit KIM-LIPI telah mengembangkan suatu sistem pengukuran acuan daya AC untuk laboratorium standar nasional dengan ketelitian pengukuran yang lebih baik dari 75 ppm pada faktor cakupan 2 dan tingkat kepercayaan 95%. Sistem tersebut berbasis Standard Watt Converter (SWC), beban semu, dan digital DC voltmeter yang telah diketahui koreksinya melalui proses kalibrasi kepada standar yang dimiliki Lembaga Metrologi Nasional Australia (NMIA) dan Lembaga Metrologi Nasional Indonesia (Puslit KIM-LIPI). Metode perbandingan terhadap sistem acuan tersebut telah diterapkan pada suatu Unit Under Calibration (UUC) yang berupa power meter berketelitian tinggi. Hal ini dilakukan untuk menampilkan unjuk kerja sistem acuan daya AC dalam proses pengukuran koreksi pembacaan dari power meter. Hasil evaluasi pada titik-titik pengukuran 120 V, 5 A, dan 53 Hz menunjukkan bahwa koreksi pembacaan terbesar adalah 133 ppm. Nilai tersebut berkesesuian dengan kelas akurasi power meter ZERA RMM3001 yaitu 0,02% atau sebesar 200 ppm. Dari hasil unjuk kerja sistem pengukuran ini maka penetapan acuan daya AC untuk laboratorium standar nasional seperti Puslit KIM-LIPI mencukupi. Kata kunci: sistem pengukuran acuan, daya AC, standard watt converter, koreksi pembacaan, power meter. Abstract Puslit KIM-LIPI has developed an AC power reference measurement system for a national standard laboratory with a measurement precision better than 75 ppm at coverage factor 2 and confidence level 95 %. The system was based on the instruments of a standard watt converter, a phantom load, and a standard digital voltmeter, which the corrections of those readings are known by calibration processes to both National Metrology Institute of Australia (NMIA) and Puslit KIM-LIPI. The comparison method of the AC power reference system has been applied to the high precision power meter as a unit under calibration (UUC). This was done to show the measurement performance of AC power reference system in the process to find the reading correction of the power meter under calibration. The measurement evaluation at 120 V, 5 A, and 53 Hz showed that the worst reading correction was 133 ppm. That value was on the agreement with the class accuracy of ZERA RMM3001 power meter which is 0,02 % or 200 ppm. The performance of the measurement system indicated that the establishment of the ac power reference for a national standard laboratory such as Puslit KIM-LIPI was adequate. Keywords: reference measurement system, AC power, standard watt converter, reading correction, power meter.

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