1. Connor O’Leary, Micah Uzuh, Brandon Zimmerman, Matthew Howard Advisor: Dr. Dyer Harris

2. Laser Tracker Vantage Dimensional metrology device Retail Price: Approx. $100,000 In-House Testing Drop test laser system before installation Test identifies unstable opto-mechanics Current test has large variability, poor repeatability Project Scope Design a system to allow accurate, repeatable drop testing of laser subsystem. 2

3. Current Drop Test 3 Shim enlarged for clarity. Actual thickness ~0.03 in

4. Current Drop Test Simulation 4

5. Questions? 5

6. Ranked Wants, Metrics, & Target Values Want/NeedAssociated Metrics Initial Testing Values Target Values Repeatable Shock Percent Error (%) ANOVA w/Tukey Test 15% p=1.3E-8 5% p>.05 Specified Shock Magnitude Acceleration (g) 80g Range of ShockAcceleration Range (g) 60-90g50-200g QuickTime to Run 3 Tests (s) 15s≤ 60s 6 Must Have Want to Have Constraints: Space on optics bench

7. Background Science: Shock Shock is the measurable acceleration of two bodies at impact Mechanics Involved (1)Energy Equations (2)Linear Motion Direction of Motion Drop Height (h) Top Block Bottom Block A simple simulation of Faro’s current set up with shim removed Shock

8. Initial Testing– Variability Between Users 8 Slow Fast Conclusion 1) Error between operators 2) Error within each operator

9. Benchmarking 9 Dynatup 8200 Drop Tower –Guiding rods to restrict and aid vertical motion –Lever system to release weight at certain height

10. 10 Concept Generation

11. Rubber Pads Rubber pads are added to design to aid in the absorption of impacts thus giving more refined and measurable drop heights to corresponding shock values Pads used –Viton –Ultra Strength Neoprene –Neoprene Spring –Butyl Rubber 11 Rubber Pads

12. Drop Tower Prototype Model The model shown (right) is the design as built Note the changes mentioned: –Latch (red) –Bottom V-block (black) Effects Using purchased V-Blocks removes capability to handle certain orientations. 12

13. Prototype Cost Summary 13 PartQty$/PartFinal Cost 2" x 6" x 12" Aluminum Plate1 $ 67.02 1/2" x 5" x 24" Steel Plate1 $ 23.36 2” x 4” x 24” Steel Plate1 $ 117.92 48" Steel Round Bar, 3/8" D4 $ 4.20 $ 16.80 3" x 4" legs x 1/4" thick x 12" long 90 Degree Angle Steel1 $ 13.72 Linear Ball Bearing for 3/8" Shaft Diameter4 $ 30.52 $ 122.08 Steel Slide Bolt1 $ 12.86 Stainless Steel Spring Loaded Latch1 $ 44.80 Various Rubber Pads Package1 $ 87.03 TOTAL COST: $ 505.59

14. Drop Tower Simulation 14

15. Prototype Testing Procedure 1.Attach accelerometer to laser subsystem 2.Each operator performed 5 drop tests with constant height and material to establish operator error 3.Single operator performed 5 drop tests for each material at various drop heights to evaluate the model Example: 15 Ultra Strength Neoprene Neoprene Spring Butyl Rubber Viton 1.5 in (5x) 1.0 in (5x).

16. Initial Testing Revisited – FARO Device 16 Slow Shim WithdrawalFast Shim Withdrawal Analysis: One-way ANOVA with Tukey post-hoc * p<0.05 () Statistical significance between users

17. Validation Testing – Designed Prototype 17 Analysis: One-way ANOVA with Tukey post-hoc * p<0.05 () NO STATISTICAL SIGNIFICANCE BETWEEN USERS

18. Material Modeling 18

19. Curve Fitting 19

20. Previous Shock Pulse 20

21. Optimized Shock Pulse 21

22. Wants, Metrics, and Target Values Revisited 22 Want/Need Associated Metrics Initial Testing Values Target Values Achieved Values Repeatable Shock Percent Error (%) 15%5% 8% ANOVA w/ Tukey Test p=1.3E-8p>.05 p>.19 Specified Shock Magnitude Acceleration (g)80g Range Adjustable Shock Acceleration Range (g) 60-90g50-200g 50-800g QuickTime to Run 3 Tests (s) 15s≤ 60s 15s Purchased latch did not perform as expected, weakening prototype performance. Refinement with original designed latch should exceed target value for repeatable shock.

23. Path Forward Suggestions for the design –Different latch –Thicker Threaded Rod –Modified Positioner Plate *These changes should even further remove variability and improve the percent error to more acceptable values. More testing for calibration to tighten up the model. Recommend a more stable testing surface to minimize outside vibrations. 23

24. Questions? 24