Photoelastic Stress Analysis Under Unconventional Loading

Volume 4: ASME/IEEE International Conference on Mechatronic and Embedded Systems and Applications and the 19th Reliability, Stress Analysis, and Failure Prevention Conference ◽

10.1115/detc2007-34966 ◽

2007 ◽

Cited By ~ 1

Author(s):

Venketesh N. Dubey ◽

Gurtej S. Grewal

Keyword(s):

Stress Analysis ◽

Phase Shifting ◽

Vertical Load ◽

Sensing Applications ◽

Shear Loads ◽

Photoelastic Effect ◽

Low Modulus ◽

Photoelastic Stress ◽

Fringe Patterns

This paper presents use of conventional photoelastic techniques under unconventional loading situations to evaluate their efficacy in sensing applications. The loading is unconventional in the sense that low modulus photoelastic material is deformed under vertical load in the direction of light travel to induce the photoelastic effect. This is atypical of conventional methods where loading is across the light travel. Both RGB calibration and phase shifting techniques have been used to study the characteristics of fringe patterns obtained under vertical and shear loads. The results obtained under these conditions are discussed with their limitations specially when this is applied for sensing applications. Finally a case study has been conducted to analyze the foot image and conclusions drawn from this have been presented.

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Tactile Whole-Field Imaging Sensor on Photoelasticity

Volume 4: ASME/IEEE International Conference on Mechatronic and Embedded Systems and Applications and the 19th Reliability, Stress Analysis, and Failure Prevention Conference ◽

10.1115/detc2007-35264 ◽

2007 ◽

Author(s):

Venketesh N. Dubey ◽

Gurtej S. Grewal

Keyword(s):

Phase Shifting ◽

Sensing Applications ◽

Shear Loads ◽

Photoelastic Effect ◽

Low Modulus ◽

Fringe Patterns ◽

Imaging Sensor ◽

Field Imaging ◽

New Strategies

The paper describes a whole-field imaging sensor developed on the principles of photoelasticity. The sensor produces colored fringe patterns when load is applied on the contacting surface. These fringes can be analyzed using conventional photoelastic techniques, however, as the loading in the present case is not conventional some new strategies need to be devised to analyze the load imprint. The loading is unconventional in the sense that low modulus photoelastic material is deformed under vertical load in the direction of light travel to induce the photoelastic effect. The paper discusses the efficacy of both RGB calibration and phase shifting techniques in sensing applications. The characteristics of fringe patterns obtained under vertical and shear loads have been studied and the results obtained under these conditions are discussed with their limitations specifically when this is applied for sensing applications. Finally a case study has been conducted to analyze a foot image and conclusions drawn from this have been presented.

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Experimental Stress Measurement Using PhotoStress-Plus: Engine Flywheel Case-Study

Volume 5: 13th Design for Manufacturability and the Lifecycle Conference; 5th Symposium on International Design and Design Education; 10th International Conference on Advanced Vehicle and Tire Technologies ◽

10.1115/detc2008-50013 ◽

2008 ◽

Author(s):

Tongele Tongele ◽

Abdul Mohammed

Keyword(s):

Stress Analysis ◽

Stress Measurement ◽

Evaluation Procedure ◽

Analysis Method ◽

Structural Components ◽

Stress Determination ◽

Working Principle ◽

Photoelastic Stress ◽

Stress Patterns

This paper presents PhotoStress-Plus, an optical photoelastic stress analysis equipment and technique, which provides an experimental estimation of stress distribution in structural components subjected to static or dynamic loading. The construction, working principle and evaluation procedure for complete stress determination is described. Using an engine flywheel as a case-study, it is found that PhotoStress-Plus in conjunction with computational or numerical stress analysis method can provide a solid and accurate understanding of stress patterns within a loaded body.

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Stress Analysis of Tire Sections

Tire Science and Technology ◽

10.2346/1.2137527 ◽

1996 ◽

Vol 24 (4) ◽

pp. 349-366 ◽

Cited By ~ 4

Author(s):

T-M. Wang ◽

I. M. Daniel ◽

K. Huang

Keyword(s):

Finite Element ◽

Internal Pressure ◽

Stress Analysis ◽

Strain Analysis ◽

Experimental Stress ◽

Inflation Pressure ◽

Substantial Agreement ◽

Finite Element Stress Analysis ◽

Strain Components ◽

Fringe Patterns

Abstract An experimental stress-strain analysis by means of the Moiré method was conducted in the area of the tread and belt regions of tire sections. A special loading fixture was designed to support the tire section and load it in a manner simulating service loading and allowing for Moiré measurements. The specimen was loaded by imposing a uniform fixed deflection on the tread surface and increasing the internal pressure in steps. Moiré fringe patterns were recorded and analyzed to obtain strain components at various locations of interest. Maximum strains in the range of 1–7% were determined for an effective inflation pressure of 690 kPa (100 psi). These results were in substantial agreement with results obtained by a finite element stress analysis.

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