APPLICATION TO STRUCTURAL ANALYSIS OF ESPI, HOLOGRAPHY AND 3D SHAPE MEASUREMENT

1. Nagasaki University, Graduate School Naoki MATSUYAMA Yasuaki SUGIHARA Tomofumi NAKYAJIMA Masataka MORI Nagasaki University Hiroshi MATSUDA APPLICATION TO STRUCTURAL ANALYSIS OF ESPI, HOLOGRAPHY AND 3D SHAPE MEASUREMENT

2. Introduction Strain gauge method ■The measurement method is easy, and precision is high ■Now the strain measurement method spreading most widely Measurement at a contact-type and fixed point ■Measurement only for gauge pasting point ■Use limit by environment, amount of strain, and fatigue Problems It is necessity of non contact and full field measurement ・ Three dimensional shape measurement ・ Holography interferometry measurement ・ Electronic Speckle Pattern Interferometry(ESPI) measurement

3. Three dimensional shape measuring system 3D coordinates of the object can be measured Feature ・ Portable and generality are abundant ・ Measurement time is short Three dimensional shape measuring system The shape of Concrete Joint and Nagasaki Peaceful Prayer was measured

4. Shape measurement of Concrete Joint Concrete Joint 3D shape data Detailed 3D coordinates of Concrete Joint surface was obtained

5. 3D shape measurement of Nagasaki Peaceful Prayer Shape data is obtained by connecting point group data, and pasting surface From 8 directions Point group data Shape data Detailed 3D coordinates of Nagasaki Peaceful Prayer surface was obtained

6. Holographic interferometry measuring system Measurement of small deformation and vibration are possible by obtaininginterference fringes Feature ・ Measurement time is short ・ Measurement in darkroom Holographic interferometry measuring system The vibration of Twisted Conical Shells and Notched Specimen was measured

7. Holography FE analysis Free vibration modes of Twisted Conical Shells Mode of vibration Specimen 8th mode 3289(Hz) 3522(Hz) Frequencies and modes of vibration almost agree with the FE analytical results

8. Vibration modes of the Notched Specimen Mode of vibration Holography FE analysis 3rd mode520(Hz) 538(Hz) Frequencies and modes of vibration almost agree with the FE analytical results

9. Electric Speckle Pattern Interferometry (ESPI) measuring system From an interference fringe of speckle provided by interference of a laser, measurement of displacement of an object is possible Feature ・ Measurement under visible light is possible ・ Non contact and full field measurement ESPI measuring system The displacement of Tensioned membraneand Defective Plate was measured

10. Wrinkle measurement of Tensioned membrane Specific in time and the place of the wrinkle generation is necessary Research of membrane structure Wrinkle Distribution of a minor principal strain ESPI measuring system enables specific in the wrinkle generation part

11. Load (N) Strain (μ) Tensile Test of the Defective Plate Specimen Load - Maximum principal strain curve The concentration of the strain was able to be confirmed to the vicinity of the breaking side at the small load level by ESPI measuring system

12. ・ Information that was not able to be seen by eyes can be acquired ・ Enormous 3D coordinate information can be acquired in a short time Summary Application of optical measurement technology to structure APPLICATION TO STRUCTURAL ANALYSIS

14. 干渉縞 Δφが２π変化するごとに 干渉縞が１本発生する ４πu Δφ＝ sinθ λ ESPIの原理 スペックルパターン 光学系 レーザー光 θ u CCDカメラ レンズ 対象物 変位uに対する位相差の増分Δφ

15. ４πu Δφ＝ sinθ λ Electric Speckle Pattern Interferometry(ESPI) measuring system Principle of ESPI Speckle pattern Optical system laser beams θ u Interference　fringes CCD Δφが２π変化するごとに 干渉縞が１本発生する lens object Increment of phase difference Δφ to displacement u

16. 長崎平和祈念像の形状計測 変位分布 応力分布