Interferometric measurement system for cost effective e-beam writer

2014 ◽  
Author(s):  
Šimon Řeřucha ◽  
Martin Šarbort ◽  
Martin Čížek ◽  
Jan Hrabina ◽  
Josef Lazar ◽  
...  
Author(s):  
Bryan W. Schlake ◽  
Brian S. Daniel ◽  
Ron Voorheis

In pursuit of improved safety, Norfolk Southern Corp. (NS) has partnered with Amberg Technologies to explore the potential benefits of a laser-based measurement system for measuring over dimensional freight rail shipments. Shipments that do not fall within a standard geometric envelope, denoted as Plate B in the Association of American Railroads (AAR) Open Top Loading Rules [1], are considered to be over dimensional, or High-Wide Loads (HWLs). Extending beyond the limits of the Plate B diagram, these loads are not permitted in unrestricted interchange service. Instead, they must be measured both at points of origin and at interchange points. For US Class I Railroads, the de facto method for measuring HWLs requires mechanical personnel to either climb on the equipment or use a ladder and physically measure the overall height and width of the load. Using a tape measure, plumb line, and 6-foot level, car inspectors, or carmen, must often make multiple measurements to determine the height or width of a critical point on the load. The summation of these measurements can be subject to mathematical human error. In addition to the inherent limitations with regards to accuracy and efficiency, this method of measurement presents considerable safety challenges. The objective of the project was to develop a portable, cost-effective and accurate measurement system to improve the day-to-day operational process of measuring HWLs and reduce human exposure to railyard hazards. Norfolk Southern worked closely with Amberg Technologies to provide a clear overview of the current measuring methods, requirements, challenges and risks associated with HWLs. Amberg then developed a prototype system (with patent pending) and successful tests have been completed at both a point of origin for NS shipments and at a location where HWLs are received at interchange. The measuring system consists of a tripod mounted laser, a specially designed track reference target (TRT) and software designed specifically for HWL measurements. The system allows car inspectors to take measurements from a safe, strategic location away from the car. As a result, this system eliminates the need to climb on the equipment or a ladder and greatly reduces the amount of time spent on and around live tracks. In addition, initial tests indicate that this technology reduces the labor time required to measure HWLs by as much as one half while improving measurement accuracy. These tests have demonstrated that a laser-based system has the potential to greatly improve the safety, efficiency and accuracy associated with measuring HWLs.


2009 ◽  
Vol 186 ◽  
pp. 012080
Author(s):  
Hirokatsu Yumoto ◽  
Hidekazu Mimura ◽  
Soichiro Handa ◽  
Takashi Kimura ◽  
Satoshi Matsuyama ◽  
...  

2014 ◽  
Vol 23 (10) ◽  
pp. 1450141
Author(s):  
MUHAMMAD AKMAL CHAUDHARY ◽  
JONATHAN LEES ◽  
JOHANNES BENEDIKT ◽  
PAUL TASKER

This paper presents a fully automated time domain, waveform measurement system, capable of measuring multi-tone waveforms up to a frequency of 14 GHz. Multi-tone waveform measurement capabilities will prove useful in enhancing the understanding of the response of devices under realistic operating conditions, and allow for detailed investigation into device problems leading to memory effects. The system, which is based around a standard sampling oscilloscope, is capable of measuring all four traveling waves simultaneously. It is a cost effective solution, capable of capturing high quality measurement data, it consists of two test sets one to measure RF components of the signal and one to measure IF components, which are then recombined before being measured by the sampling oscilloscope. Vector error correction is applied to the measured data to fully calibrate the system to the device plane, ensuring any dispersion in the connecting hardware is removed. A multi-tone waveform sampling method is employed, ensuring the waveforms are captured in the most efficient manner. Device results are presented showing the multi-tone voltage and current waveforms at the device plane. Some useful applications of the system are demonstrated and explained.


Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6329
Author(s):  
Ruijun Li ◽  
Yongjun Wang ◽  
Pan Tao ◽  
Rongjun Cheng ◽  
Zhenying Cheng ◽  
...  

Laser beam drift greatly influences the accuracy of a four degrees of freedom (4-DOF) measurement system during the detection of machine tool errors, especially for long-distance measurement. A novel method was proposed using bellows to serve as a laser beam shield and air pumps to stabilize the refractive index of air. The inner diameter of the bellows and the control mode of the pumps were optimized through theoretical analysis and simulation. An experimental setup was established to verify the feasibility of the method under the temperature interference condition. The results indicated that the position stability of the laser beam spot can be improved by more than 79% under the action of pumping and inflating. The proposed scheme provides a cost-effective method to reduce the laser beam drift, which can be applied to improve the detection accuracy of a 4-DOF measurement system.


Author(s):  
Graham Scott ◽  
Ema Chillingworth ◽  
Matthew Dick

Compliance with track standards and control of maintenance costs are critical aspects of the management of railroads. To facilitate this, track geometry measurement systems have evolved to allow monitoring of key track geometry parameters from moving trains. This paper describes how DeltaRail’s Trackline Two™ track geometry measurement system has been developed to overcome key technical shortcomings in existing systems. The resulting step change provides a cost-effective, robust, compact measurement system suitable for use on the broadest possible range of rail vehicles and networks, from a tram to a TGV. Extensive testing has demonstrated full compliance with appropriate standards. Significant improvements in reliability and repeatability of data have enabled DeltaRail to produce a modular system capable of sending data direct to value-adding analysis tools such as TrackMaster™ and VAMPIRE® so that track maintenance management can be optimized around train fleet and operational conditions. The system is easily operated in unattended mode allowing collection of track geometry data from in-service trains, increased frequency of data collection, and pointing the way for the track maintainers to realize significant value from integrated analysis and management options.


Author(s):  
Teddy Surya Gunawan ◽  
Yasmin Mahira Saiful Munir ◽  
Mira Kartiwi ◽  
Hasmah Mansor

Recently, there is increasing public awareness of the real time air quality due to air pollution can cause severe effects to human health and environments. The Air Pollutant Index (API) in Malaysia is measured by Department of Environment (DOE) using stationary and expensive monitoring station called Continuous Air Quality Monitoring stations (CAQMs) that are only placed in areas that have high population densities and high industrial activities. Moreover, Malaysia did not include particulate matter with the size of less than 2.5μm (PM2.5) in the API measurement system. In this paper, we present a cost effective and portable air quality measurement system using Arduino Uno microcontroller and four low cost sensors. This device allows people to measure API in any place they want. It is capable to measure the concentration of carbon monoxide (CO), ground level ozone (O3) and particulate matters (PM10 & PM2.5) in the air and convert the readings to API value. This system has been tested by comparing the API measured from this device to the current API measured by DOE at several locations. Based on the results from the experiment, this air quality measurement system is proved to be reliable and efficient.


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