scholarly journals Design framework for high-speed 3D scanning tools and development of an axial focusing micromirror-based array

2020 ◽  
Author(s):  
Nathan Tessema Ersumo ◽  
Cem Yalcin ◽  
Nick Antipa ◽  
Nicolas Pegard ◽  
Laura Waller ◽  
...  
Keyword(s):  
High Speed ◽  
3D Scanning ◽  
Design Framework

Uniaxial High-Speed Micro-Scale Three-Dimensional Surface Topographical Measurements Using Fringe Projection

2020 ◽  
Author(s):  
Yi Zheng ◽  
Beiwen Li
Keyword(s):  
High Speed ◽  
Sample Surface ◽  
3D Scanning ◽  
In Situ Monitoring ◽  
Fringe Projection ◽  
Depth Information ◽  
Projection Technique ◽  
Projection System ◽  
Loop Control

Abstract In-situ inspection has drawn many attentions in manufacturing due to the importance of quality assurance. Having an accurate and robust in-situ monitoring can assist corrective actions for a closed-loop control of a manufacturing process. The fringe projection technique, as a variation of the structured light technique, has demonstrated significant potential for real-time in-situ monitoring and inspection given its merits of conducting simultaneous high-speed and high accuracy measurements. However, high-speed 3D scanning methods like fringe projection technique are typically based on triangulation principle, meaning that the depth information is retrieved by analyzing the triangulation relationship between the light emitter (i.e., projector), the image receiver (i.e., camera) and the tested sample surface. Such measurement scheme cannot reconstruct 3D surfaces where large geometrical variations are present, such as a deep-hole or a stair geometry. This is because large geometrical variations will block the auxiliary light used in the triangulation based methods, which will resultantly cause a shadowed area to occur. In this paper, we propose a uniaxial fringe projection technique to address such limitation. We measured a stair model using both conventional triangulation-based fringe projection technique and the proposed method for comparison. Our experiment demonstrates that the proposed uniaxial fringe projection technique can perform high-speed 3D scanning without shadows appearing in the scene. Quantitative testing shows that an accuracy of 1.15% can be obtained using the proposed uniaxial fringe projection system.

scholarly journals High-Speed Accurate 3D Scanning of Human Motion Sequences

2015 ◽  
Author(s):  
Christian BRAUER BURCHARDT ◽  
Stefan HEIST ◽  
Ingo SCHMIDT ◽  
Peter LUTZKE ◽  
Peter KUHMSTEDT ◽  
...  
Keyword(s):  
High Speed ◽  
3D Scanning ◽  
Human Motion

scholarly journals high-speed structured light based 3D scanning using an event camera

2021 ◽  
Author(s):  
Xueyan Huang ◽  
Yueyi Zhang ◽  
Zhiwei Xiong
Keyword(s):  
High Speed ◽  
Structured Light ◽  
3D Scanning ◽  
Event Camera

scholarly journals An Automatic Design Framework for Real-Time Power System Simulators Supporting Smart Grid Applications

Electronics ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 299 ◽  
Author(s):  
Eleftherios Mylonas ◽  
Nikolaos Tzanis ◽  
Michael Birbas ◽  
Alexios Birbas
Keyword(s):  
Smart Grid ◽  
Power System ◽  
Real Time ◽  
High Speed ◽  
High Performance ◽  
Power Grids ◽  
Low Latency ◽  
Successful Implementation ◽  
Automatic Design ◽  
Design Framework

Smart grid technology is the next step to the evolution of classical power grids, providing robustness, reliability, and security throughout the network, enabling real-time management and control. To achieve these goals, distributed computing (microgrid concept) and intelligent control algorithms, tailored to the nature and needs of the network under study, are necessary. To deal with the vast diversity of power grids, being able to capture the dynamics of any given network, and create tools for network analysis, apparatus testing, and power grid management, an automatic design framework for real-time power system simulators is needed. In this article, a prototype of this approach is presented, employing Field Programmable Gate Array (FPGA) platforms due to their reconfigurability that enables low-power, low-latency, and high-performance designs, as a first attempt towards an open source platform, compatible with the majority of hardware design suites. It comprises two major parts: (i) a user-oriented section, built in Matlab/Simulink; and (ii) a hardware-oriented section, written in Matlab and Very High Speed Integrated Circuit (VHSIC)-Hardware Description Language (VHDL) code. To verify its functionality, two test power networks were given in a schematic format, analyzed through Matlab code and turned into dedicated hardware simulators with the aid of the VHDL template. Then, simulation results from Simulink and the prototype were compared for error estimation. The results show the prototype’s successful implementation with minimal resources utilization, high performance and low latency in the order of nanoseconds in Xilinx 6- and 7-series FPGAs, therefore proving its modularity and efficient use in many different scenarios, meeting low-latency/real-time requirements while enabling further smart grid research.

Uniaxial High-Speed Micro-Scale 3D Surface Topographical Measurements Using Fringe Projection

2020 ◽  
Author(s):  
Yi Zheng ◽  
Beiwen Li
Keyword(s):  
Real Time ◽  
High Speed ◽  
Structured Light ◽  
3D Scanning ◽  
In Situ Monitoring ◽  
Physical Contact ◽  
Fringe Projection ◽  
Depth Information ◽  
Projection Technique

Abstract In-situ inspection has drawn many attentions in manufacturing due to the importance of quality assurance. With the rapid growth of additive manufacturing technology, the importance of in-line/in-situ inspections has been raised to a higher level due to many uncertainties that could occur during an additive printing process. Given this, having accurate and robust in-situ monitoring can assist corrective actions for a closed-loop control of a manufacturing process. Contact 3D profilometers such as stylus profilometers or coordinate measuring machines can achieve very high accuracies. However, due to the requirement for physical contact, such methods have limited measurement speeds and may cause damage to the tested surface. Thus, contact methods are not quite suitable for real-time in-situ metrology. Non-contact methods include both passive and active methods. Passive methods (e.g., focus variation or stereo vision) hinges on image-based depth analysis, yet the accuracies of passive methods may be impacted by light conditions of the environment and the texture quality of the surface. Active 3D scanning methods such as laser scanning or structured light are suitable for instant quality inspection due to their ability to conduct a quick non-contact 3D scan of the entire surface of a workpiece. Specifically, the fringe projection technique, as a variation of the structured light technique, has demonstrated significant potential for real-time in-situ monitoring and inspection given its merits of conducting simultaneous high-speed (from 30 Hz real-time to kilohertz high speeds) and high accuracy (tens of μm) measurements. However, high-speed 3D scanning methods like fringe projection technique are typically based on triangulation principle, meaning that the depth information is retrieved by analyzing the triangulation relationship between the light emitter (i.e., projector), the image receiver (i.e., camera) and the tested sample surface. Such measurement scheme cannot reconstruct 3D surfaces where large geometrical variations are present, such as a deep-hole or a stair geometry. This is because large geometrical variations will block the auxiliary light used in the triangulation based methods, which will resultantly cause a shadowed area to occur. In this paper, we propose a uniaxial fringe projection technique to address such limitation. We measured a stair model using both conventional triangulation based fringe projection technique and the proposed method for comparison. Our experiment demonstrates that the proposed uniaxial fringe projection technique can perform high-speed 3D scanning without shadows appearing in the scene. Quantitative testing shows that an accuracy of 35 μm can be obtained by measuring a step-height object using the proposed uniaxial fringe projection system.

Research on the Method of the Calibration of 3D Scanning Probe System Based on the Least Squares of Subsection-Variable Parameters

2012 ◽  
Vol 468-471 ◽  
pp. 1005-1012
Author(s):  
Peng Wan ◽  
Jun Jie Guo ◽  
Pei Lin Wu
Keyword(s):  
Least Squares ◽  
High Precision ◽  
High Speed ◽  
Least Squares Method ◽  
Contact Point ◽  
Calibration Method ◽  
3D Scanning ◽  
Scanning Probe ◽  
High Precision Measurement ◽  
Continuous Scanning

Traditional one-dimensional, two-dimensional probe can only measure the micro displacement in one or two directions of space, therefore highly-efficient and highly-precise measurement requirements of the surface of the complex gear can’t be satisfied. Because 3D scanning probe can measure the micro-displacement in three mutually perpendicular directions of space, with it, continuous scanning motion measurement can be achieved and a large number of data points in three directions of space can be measured in a very short time, it is widely used in gear measurement industry at home and abroad. However, because of the limitations of mechanical structure of 3D scanning probe, installation errors and environmental factors, the measured three directions can’t always be strictly vertical, and in the measurement, there will be the interference and the coupling phenomenon among the three directions. The study about how to ensure the highly precise characteristics of 3D scanning probe using a reasonable calibration method has become hot and difficult. In the paper, a new calibration method is proposed, the different regions on the standard ball were continuously contacted by 3D scanning probe, and let the probe step 10 times on the each contact point of standard ball, 10 group of points data were read out. The point of subsection was determined based on the deformation of the probe in the experiment, the data of the probe collected in each segment were fitted by using of the least squares method. Several calibration matrices were so obtained, the precise calibration of 3D scanning probe can be achieved. This method is finally verified by experiment. The experimental results show that the method of calibration is feasible, and has the advantages of high-speed and high-precision, which lays a solid foundation for high-precision measurement of 3D scanning probe.

Microfabrication research at the National Submicron Facility

1983 ◽  
Vol 41 ◽  
pp. 86-89
Author(s):  
E.D. Wolf
Keyword(s):  
Integrated Circuits ◽  
Particle Physics ◽  
High Speed ◽  
New Technology ◽  
High Energy ◽  
High Energy Particle ◽  
New Science ◽  
Wide Range ◽  
Intermediate Domain ◽  
Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

Vacuum System to Minimize the Specimen Contamination of High-Performance EM

1977 ◽  
Vol 35 ◽  
pp. 68-69
Author(s):  
N. Yoshimura ◽  
K. Shirota ◽  
T. Etoh
Keyword(s):  
Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
High Vacuum ◽  
Vacuum System ◽  
Pump System ◽  
Pumping System ◽  
Diffusion Pump ◽  
Almost All ◽  
Cascade Type

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.

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