1. Jesus Benhumea Kevin Stokely Matt Aggleton Advisor: Dr. Scott Franklin Jamming in 2-D Prolate Granular Material Systems. *Petroleum Research Fund #39132-GB9

2. Outline Background Experimental Setup Video Data Analysis Data Conclusion

3. Background Prolate particles are characterized by large aspect ratio (  = L/W > 10) –Piles are much more rigid than ordinary granular materials Jamming: To cause (moving parts, for example) to lock into an unworkable position –Oil industry –Farming –Manufacturers of items such as Nails, pens, etc.. –Timber Industry –Anywhere prolate granular materials are found What Triggers Jamming to occur more frequently?

4. Experimental Setup 2-D flat surface Dimensions 12”x20” Square Brass Rods 2.5” X.125”  = 20 Packing fraction = Area of rods/ Total Area

5. A.5” probe is driven through the pile.

6. The rods are laid and spread out by hand An initial image is taken and analyzed to ensure randomness and isotropy Angular Distribution

7. What Are we are Looking for Total number of Particles that are disturbed in a run? How far ahead, above, and below does the disturbance reach? How many particles are pushed off the plate? What force is felt by the probe from the particles?

8. Video Data  = 40%

9. Video Data  = 13%

10. We Subtract Images to determine which rods have moved. Bright Spots Indicate Disturbance Video Analysis

11. Subtracted Video

12. More particles lead to more moving in disturbance

13. Motion of Particles ahead of the Dot

14. Motion of particles above and below the dot.

15. Rods pushed off of the plate.

16. Conclusion Jamming and more body like movements occur around 26% Future Plans –We plan to include a force sensor to measure the forces that occur –Track the movement of one or more particles with fluorescent paint. –Make the transition to multi-level piles