A Real-Time DSPI System for Measuring Surface Deformation in Clamped Bolted Joints

2008 ◽  
Author(s):  
Aidong Meng ◽  
Sayed A. Nassar
Keyword(s):  
Real Time ◽  
Vibration Isolation ◽  
Surface Deformation ◽  
Plane Surface ◽  
Speckle Pattern ◽  
The Real ◽  
Time Deformation ◽  
Out Of Plane ◽  
Phase Data ◽  
Set Up

A Digital Speckle Pattern Interferometry (DSPI) system is developed for the real-time measuring and monitoring the out-of-plane surface deformation around tightened threaded fasteners that are used to clamp bolted assemblies. Spatial phase shifting is employed to quantitatively determine the distribution of phase data by introducing a spatial carrier fringe pattern to the speckle interferogram. This is achieved by leading the object and reference beams to two separate apertures. The configuration is also suitable for collecting the real-time deformation during bolt tightening. The experimental DSPI system is set-up with optical components on a vibration-isolation table. A Matlab software is developed for the image acquisition and phase data calculation, which yields the out-of-plane surface deformation caused by the bolt preload. An aluminum joint is used with an M12 steel fastener. For miniature screw application, however, a plastic joint is used for collecting data.

A Novel Optical Method for Real-Time Control of Bolt Tightening

2011 ◽  
Vol 133 (6) ◽  
Author(s):  
Aidong Meng ◽  
Sayed A. Nassar ◽  
Douglas Templeton
Keyword(s):  
Real Time ◽  
Vibration Isolation ◽  
Surface Deformation ◽  
Plane Surface ◽  
Speckle Pattern ◽  
Joint Surface ◽  
The Real ◽  
Bolt Preload ◽  
Out Of Plane ◽  
Phase Data

A digital speckle pattern interferometry (DSPI) system is developed for the real-time measurement and monitoring of the out-of-plane surface deformation around a preloaded bolt head or nut. The proposed system is specifically developed for the dynamic control of the bolt tightening process by continuously monitoring the out-of-plane joint surface deformation that will have been independently correlated to the bolt preload. Spatial phase shifting is employed to quantitatively determine the distribution of phase data by introducing a spatial carrier fringe pattern to the speckle interferogram. This is achieved by leading the object and reference beams through two separate apertures. The configuration is also suitable for collecting the real-time surface deformation during bolt tightening. The experimental DSPI system is set-up with optical components on a vibration-isolation table. A MATLAB software is developed for image acquisition and phase data calculations that yield the out-of-plane surface deformation caused by the bolt preload. The test fixture uses an M12 steel fastener and aluminum joint. For miniature screw applications, however, a plastic joint is used.

Application of 3D Virtual Scene Building Technology Based on OSG in Gas Station Training Simulation System

2014 ◽  
Vol 918 ◽  
pp. 252-257
Author(s):  
Jian Mei Song ◽  
Zhong Hua Yan ◽  
Hao Yuan
Keyword(s):  
Real Time ◽  
Simulation System ◽  
Virtual Scene ◽  
The Real ◽  
Building Technology ◽  
Model Library ◽  
Extensible Markup ◽  
Training Simulation ◽  
Gas Station ◽  
Set Up

For a gas station training simulation system, the real time and reality of scene directly affect the application of system. In order to solve this problem, we used 3D virtual scene building technology based on OpenSceneGraph (OSG) to build gas station scene. Technology of levels of detail (LOD) was used to improve the real-time ability of the system during entity modeling. And then based on 3D entity model library and information files in Extensible Markup Language (XML), we built the parametric library and set up the gas station scene, which provided function information and attribute information. Experimental results show that the scene of virtual gas station can not only greatly improve the reality and immersion of system, but also well support the real-time simulation. Now, 3D virtual scene building technology based on OSG has applied successfully in gas station training simulation system, which provides feasible evidence for engineering simulation to solve practical problems.

scholarly journals A Real-Time Deformation Monitoring Method for Large-Scale Structure Based on Relay Camera

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Chuan He ◽  
Lianxiong Liu ◽  
Changhua Hu
Keyword(s):  
Real Time ◽  
Large Scale ◽  
Large Scale Structure ◽  
Deformation Monitoring ◽  
Scale Structure ◽  
Monitoring Method ◽  
The Real ◽  
Intrinsic Parameters ◽  
Time Deformation ◽  
Extrinsic Parameters

In the process of the deformation monitoring for large-scale structure, the mobile vision method is often used. However, most of the existent researches rarely consider the real-time property and the variation of the intrinsic parameters. This paper proposes a real-time deformation monitoring method for the large-scale structure based on a relay camera. First, we achieve the real-time pose-position relationship by using the relay camera and the coded mark points whose coordinates are known. The real-time extrinsic parameters of the measuring camera are then solved according to the constraint relationship between the relay camera and the measuring camera. Second, the real-time intrinsic parameters of the measuring camera are calculated based on the real-time constraint relationship among the extrinsic parameters, the intrinsic parameters, and the fundamental matrix. Finally, the coordinates of the noncoded measured mark points, which are affixed to the surface of the structure, are achieved. Experimental results show that the accuracy of the proposed method is higher than 1.8 mm. Besides, the proposed method also possesses the real-time and automation property.

Interactive Two-Stage Rendering Technique of Deformable Part Through Haptic Interface

2011 ◽  
Author(s):  
Zhaoguang Wang ◽  
Georges Dumont
Keyword(s):  
Real Time ◽  
Degrees Of Freedom ◽  
Rigid Body Dynamics ◽  
Haptic Interaction ◽  
Two Stage ◽  
Deformation Spaces ◽  
The Real ◽  
Time Deformation ◽  
Main Challenge ◽  
On Line

Virtual Reality technology has been widely applied in the background of industrial evaluation applications. However, a large majority of these applications are focusing on haptics-based assemblies which mainly deal with rigid-body dynamics. Here we concern the real-time haptic interaction with deformable mock-ups aiming at the industrial design evaluation of mechanical parts. The main challenge of this application is that a tradeoff between the deformation accuracy and the interaction performance has to be achieved. In this paper, we propose a two-stage method for a real-time deformation modelling by combining an off-line pre-computation phase and an on-line deformation interaction phase. The key contributions of this paper lie on two aspects. First, during off-line phase, we propose a mesh analysis method which allows us to pre-compute different deformation spaces by anticipating the evaluation scenarios. Moreover, a real-time switch among different deformation spaces is developed so that the on-line deformation computation can focus on degrees of freedom where necessary with respect to users’ interactions. Second, during on-line phase, we apply a division scheme to divide the deformation process into two separate modules which are implemented on different threads to ensure the haptic interaction performance. Experiments are carried out based on a prototype implementation concerning different models of growing complexity. The deformation accuracy and the real-time performance are discussed.

Model based real-time control of sewer system using fuzzy-logic

1997 ◽  
Vol 36 (8-9) ◽  
pp. 343-347 ◽  
Author(s):  
L. Fuchs ◽  
T. Beeneken ◽  
P. Spönemann ◽  
C. Scheffer
Keyword(s):  
Fuzzy Logic ◽  
Real Time ◽  
Control Device ◽  
Real Time Control ◽  
Sewer System ◽  
Rule Based ◽  
The Real ◽  
Time Control ◽  
Set Up ◽  
Final System

This paper describes the use of the sewer model HYSTEM-EXTRAN in combination with a rule based control device using fuzzy-logic to simulate the real-time control of a sewer system. The rules for the control of the system were set up with the help of optimization procedures. The advantage of the procedure is proved by comparing the uncontrolled versus the controlled state in a simulated mode for an existing sewer system. The final system was installed and tested within the sewer system.

An approach to monitor the real-time deformation during heat treatment of 3D-printed glass

2021 ◽  
Author(s):  
Firas J. Hmood ◽  
Janka Wilbig ◽  
Dagmar Nicolaides ◽  
Andrea Zocca ◽  
Jens Günster
Keyword(s):  
Heat Treatment ◽  
Real Time ◽  
The Real ◽  
Time Deformation ◽  
3D Printed

scholarly journals Engineering Project Real-time Objective Monitor Based on Grid Management and Buffer Analysis

2016 ◽  
Vol 10 (1) ◽  
pp. 794-806
Author(s):  
Heyun Dong ◽  
Jian Zhang ◽  
Shisen Lv
Keyword(s):  
Real Time ◽  
Grid Cell ◽  
Project Managers ◽  
Engineering Project ◽  
The Real ◽  
Buffer Analysis ◽  
Set Up ◽  
Tennis Court ◽  
Engineering Projects ◽  
Grid Management

Engineering projects often face a great number of uncertainties which will lead projects to deviate from the anticipated objective. This paper carried out a detailed study on real-time monitoring of objective deviation in engineering projects, and it will help project managers monitor the state of engineering project better. A Grid Management (GM) method was used to set up a monitor structure, and the real-time monitor grid structure was constructed in level, milestone and objective dimensions. The buffer analysis method was designed to measure the level of objective deviation. The objective deviation level is based on the result of the grid cell buffer analysis. The principal part construction of Shenyang Olympic Tennis court was selected as the example to illustrate the real-time monitor process in detail. The results indicated that the proposed real-time objective monitor method makes it possible for project manager to real-time monitor all the main objectives in one model and carry out management, and decision-making in a more macro perspective.

scholarly journals Characterization of Shear Horizontal Waves Using a 1D Laser Doppler Vibrometer

Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2467
Author(s):  
Alaa Elhady ◽  
Eihab M. Abdel-Rahman
Keyword(s):  
Acoustic Waves ◽  
Surface Deformation ◽  
Plane Surface ◽  
Poisson Ratio ◽  
Surface Acoustic Waves ◽  
Laser Doppler Vibrometer ◽  
Element Analysis ◽  
Out Of Plane ◽  
Plane Displacement ◽  
Shear Horizontal

We developed a new technique for the detection of shear horizontal surface acoustic waves (SH-SAW) using a one-dimensional laser-based Doppler vibrometer. It measures the out-of-plane surface deformation at the fingertip of an interdigitated transducer (the boundary of the wave aperture) and uses it to estimate the instantaneous in-plane displacement field given the substrate Poisson ratio. It can also estimate the degree of surface confinement (wave decay rate). The proposed approach was first verified using finite element analysis (FEA) and demonstrated experimentally using a Bleustein–Gulyaev resonator.

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