1. PACE TERM PROJECT Alex Furse and Mike Milewski

2. As Design Engineers we were responsible for the design of a deck lid (trunk) of a new automobile. The design criteria required was that the motion of the deck lid was constrained to move along a predetermined path. Three positions of the Deck lid were specified: 1) closed, 2) midpoint and 3) open. The assignment was to design a mechanism using Unigraphics NX-3 Motion that will move the deck lid along a path through the three positions. It was assumed that the deck lid and linkage was two- dimensional and of negligible mass. The Deck lid cross section CAD geometry was provided in IGES format. Only the driver ground pivot was fixed. P A C E Project Objectives Alex Furse and Mike Milewski

3. P A C E Project Constraints Alex Furse and Mike Milewski Driver Ground Pivot Figure 1a. Initial Position P A C E

4. Project Constraints Alex Furse and Mike Milewski Figure 1b. Middle PositionFigure 1c. Open Position P A C E

5. Method of Approach Alex Furse and Mike Milewski

6. Brainstorming Researching existing hinge designs P A C E Research and Planning Alex Furse and Mike Milewski Figure 1a. BMW hinge. Figure 1c. Plymouth hinge. Figure 1b. Alfa hinge.

7. Sketching Alternative designs - Roller / track system P A C E Concepts Alex Furse and Mike Milewski Figure 2. Roller Model

8. Trial and Error - Physical Paper Linkages - Working Model 2D - Solid Works - Graphical Sketching P A C E Motion Analysis Alex Furse and Mike Milewski Figure 3c. Graphical Sketching Figure 3a. Physical Paper Linkages Figure 3b. Working Model

9. Analytical - Synthesis of Mechanism: Analytical Design of a Four-Bar Mechanism for Three-position Rigid-body Guidance Equation (11.7-4) x B1 (A 13n C 1n + A 23n S 1n – x O2 C 1n – y O2 S 1n + x O2 ) + y B1 (A 23n C 1n – A 13n S 1n + x O2 S 1n – y O2 C 1n + y O2 ) = A 13n x O2 + A 23n y O2 – ½(A 13n 2 + A 23n 2 ) Using Equation (11.7-4) with the assistance of Matlab and Excel we were able to find the various link lengths and positions. P A C E Motion Analysis Alex Furse and Mike Milewski

10. P A C E Results Alex Furse and Mike Milewski Figure 4. Perspective

11. P A C E Results Alex Furse and Mike Milewski Figure 5a. Initial Position

12. P A C E Results Alex Furse and Mike Milewski Figure 5b. Mid Position

13. P A C E Results Alex Furse and Mike Milewski Figure 5c. Open Position

14. P A C E Results Alex Furse and Mike Milewski Video 1. Open to Close Motion

15. Designed to minimize the effect of pinching - bend - spacers tolerances link hole: + 1 thou pin: - 1 thou center to center: + 10 thou bends: +/- 1 degree P A C E Optimization Alex Furse and Mike Milewski Figure 6a. link bend Figure 6b. spacer

16. Trunk lid gas piston - damping - easy use: little force required to open trunk lid - multiple locations but placed so its following the shortest distance P A C E Optimization Alex Furse and Mike Milewski Figure 7. Piston and Truck Lid

17. Designed links so that they can be easily manufactured. material: mild steel 2 stage process - sheet metal pieces cut out with dye - stamped into shaped cheap process interchangeable: links and coupler link can be used for both sides P A C E Manufacturing Alex Furse and Mike Milewski Figure 8. Coupler flat

18. reduce sheet metal thickness achieved by press fitting a bushing in the link bosses to maintain contact area of pins and links and reduce wear Rubber Sock - decreases wear and contact stress - damps closure position P A C E Improvements Alex Furse and Mike Milewski Figure 9b. link sock Figure 9a. Bushings

19. P A C E PACE Goals Alex Furse and Mike Milewski