Fiona’s Bow

1. Fiona’s Bow

2. Design Team Harvest Montemayor Fahad Al-Subaiei Samuel Zerbib Matt Joganic

3. Karin Hallberg Fiona Carroll The Clients NAU instructor 13-year old violinist

4. Problem Definition Current attachment is heavy – 28 grams Does not fit her hand as it has grown Her hand slips out when playing fast Hand position is uncomfortable for long periods of time Inhibits sound quality by touching bow hairs

5. Do NOT change the violin bow • Light-weight • Typical bow: 52 grams = 3 ounces • Custom fit for pinky and thumb • Non-slip grip • Allow for tone quality Requirements

6. Violin Research • Violin techniques and playing • Concert recitals and performances • Bow physics and vibrations

7. Fiona’s hand condition Better understanding of range of motion and muscle strength Full range of motion in her wrists Missing 3 central metacarpals and the 5th proximal phalanx Missing tendons that allow knuckle bending Motion of movement in thumb is only in one plane

8. Physical Model of Hand1 Valuable reference tool One solution to a problem we had early on with Fiona’s shyness Used for measurements of the size of Fiona’s fingers and distance between fingers Easier for us to build and test the prototypes before we give them to Fiona

9. Helped to see what was already tried Previous attachment attempts

10. Wood • Foam • Machineable Wax • ABS • PVC • LDPE • HDPE • Rubber • Nylon • Teflon • Aluminum • Carbon Fiber • Delrin Materials research • Donation from Carl’s Plastics • From Minneapolis

11. Prototype 1 • Light-weight attachment • Low-weight design would improve balance • Attachment would not be in contact with bow hairs

12. Prototype 2 • Light-weight attachment fit-form material • Polyurethane inserts for finger holes • Improved comfort and grip-ability

13. Prototype 3 • Ball-Joint between attachment and bow • Creates tripod action giving improved leverage • Allowing wider range of movement

14. Prototypes t 200 hours work time

15. Each prototype considered in detail by Fiona • Feedback questionnaires completed, • prototypes rated • ‘What did you think?’ • We had to provide Fiona a design with which she felt most comfortable • ‘Should be simple, light- weight, comfortable,’ Adrian Anantawan, Prototype feedback

16. Helped to refine design • Reduce extra weight SolidWorks model

17. Two piece • design Final Design • Universal fit • Any bow • Any location • Thumb hole is off • the bow hairs

18. 2 pass curve generation based off of point cloud scan data Next Engine 3-D scanner Analysis

19. Audi-Graph Program • Display of different • harmonic frequencies • for each note • Measures “timbre” • -A measure of sound • quality • Allow us to compare • amplitude and envelope Analysis

20. Budget

21. Conclusions

22. Conclusions

23. Conclusions

24. Conclusions

25. Initially hoped to calculate a ‘perfect’ solution • Quickly realized that our design depended on Fiona’s interaction and opinion • We were not dealing with machines, people will directly interact with our design • Our goal was to make Fiona as comfortable as possible, the more she likes the attachment , the more she will want to play and advance Final Thoughts

26. Questions ?