Instructor: Lichuan Gui lichuan-gui@uiowa

1. Measurements in Fluid Mechanics058:180 (ME:5180)Time & Location: 2:30P - 3:20P MWF 3315 SCOffice Hours: 4:00P – 5:00P MWF 223B-5 HL Instructor: LichuanGui lichuan-gui@uiowa.edu Phone: 319-384-0594 (Lab), 319-400-5985 (Cell) http://lcgui.net

2. Lecture 38. Stereo high-speed imaging

3. Stereo High-speed Imaging - High-speed camera Gray value resolution 10-bit CMOS sensor 17.5µm pixels Frame rate & digital resolution 10241024 @ 2000 fps 1024256 @ 8000 fps

4. Stereo High-speed Imaging - Optical configuration outside the camera Mirror image Mirror Lens Front view Alate Side view Mirror Mirror image

5. Lens adaptor Block Image sensor (1024256) Slit apertures Mirrors Stereo High-speed Imaging - Optical configuration inside the camera Lens Mirror images

6. High-speed camera Mirrors Back lighting Tethered fire ant alate Microphones Stereo High-speed Imaging - Experimental setup with sound recording

7. Stereo High-speed Imaging - Experimental setup with sound recording Sound recorded from bottom & rear with MCDL

8. Raw image Background Processed Stereo High-speed Imaging - Sample image & postprocessing

9. Stereo High-speed Imaging - Synchronize motion w. sound in one period 70 frames in the period of 8.8 ms (114Hz), bar chart represents sound pressure

10. Stereo High-speed Imaging - Improved system for wing motion reconstruction • New optic table and magnetic holders for higher precision • New template for adjusting mirror angles to ensure 90o • difference between front and side- views - Tested ant body carefully oriented

11. O: root of the wing T: tip of the wing 3: the 3rd point at the wing surface Stereo High-speed Imaging - Position & orientation of the wing • the wing assumed to be a planar surface without thickness

12. Stereo High-speed Imaging - Wing root position More frames may be necessary for higher accuracy & reliability

13. Axis's Axis of the wing: OT Axis of ant body: OZ Planes Pink: wing surface Angles Yellow: OT & OZ xy: wing angle in xy-plane zy: wing angle in yz-plane : angle between wing surface & plane through OT & OZ Stereo High-speed Imaging - 3D view of the wing surface

14. Wing surface function: OT&OZ surface function: Wing rotation angle: Stereo High-speed Imaging - Data reduction equations

15. Stereo High-speed Imaging - Example I: BIFA male test on July 8, 2006 Body weight: 5.5 mg Body length: 6 mm Image size: 590190 pixels, digital resolution: 22.35 pixel/mm

16. Stereo High-speed Imaging - Wing tip position of the BIFA male

17. 17 Stereo High-speed Imaging - Wing angles of the BIFA male

18. Stereo High-speed Imaging - High resolution picture of the forewing Image size: 850×300 pixels Digital resolution: 128 pixel/mm O T

19. H L Stereo High-speed Imaging - High resolution picture of the hindwing Image size: 850×300 pixels Digital resolution: 128 pixel/mm O T Gray value distribution: G(L,H)

20. Front view image: gf(x,y)=G(L,H) H Side view image: (x,y,z) gs(z,y)=G(L,H) L Top view image: gt(x,z)=G(L,H) Stereo High-speed Imaging - Simulating images form three view angles

21. Stereo High-speed Imaging - Original (top) and simulated (bottom) images

22. Stereo High-speed Imaging - Reconstructed 3D view of the male

23. 23 Stereo High-speed Imaging - Overlapped image of 74 frames

24. Stereo High-speed Imaging • Reference •  Gui L, Fink T, Cao Z, Sun D, Seiner JM and Streett DA (2010) Fire ant alate wingmotion data and numerical reconstruction. Journal of Insect Science 10:9,available online: http://insectscience.org/10.19