Overview of Status of Analysis, Design, Fabrication, Tests, etc.
Preliminary energy calculations
Accelerating plate through specified impulse profiles
Modal analysis
Hand calculation of thin plates
FEA of thin plates: free and fixed at corners
FFT of impulse profiles
Accomplishments from Previous Week
Thoughts on impulse shaping
Peak g ~ Velocity
Impulse time ~ material stiffness
Bend a beam to control impulse time (versus pure compression)
Problem definition
Continue modal analysis (add holes to hand calculations, do further FEA)
Continuum mechanics: what velocity and material stiffness leads to impulse profile
Goals for Next Week (list names after each item). Use specific and measurable objectives.
Risk reduction
Energy requirements - Roy (fixture), Leighy (head)
Beam bending (is it too soft? Too much adjustment? Too little?) - Leighy (after above)
Energy analysis on impact head: how to get energy into head (gravity? Pneumatic?) - Troy
Get correct natural frequencies of fixture etc. - Sam
Ask ATA for analysis help on continuum mechanics (what acceleration profile comes from a certain velocity and structural stiffness?) - Pretty much everyone
Sponsor Comments from Last Meeting and Actions Taken to Address these Comments
Boundary conditions specified
Article to be fixed to some excitation plate (accelerates per given impulse profiles)
Free from fixture plate to "ground" reference (ideally: article attached to fixture, accelerated in outer space)
Material thoughts
Higher stiffness/weight gives higher natural frequency
fixture needs to have high freq. compared to article, fixture to ground should have low freq. compared to article
All in person on 03/04
Instructor Comments from Last Meeting and Actions Taken to Address these Comments
Use rounded tip to ensure singular contact only - 03/03 in person (class)
Comments from Other Students in the Class
None so far
Risks and Areas of Concern
Energy required to accelerate plate
Gravity powered means large heights
Other methods may be expensive (fast pneumatic cylinder w/ long throw is expensive)
Beam bending impact head (see goals for next week)
Resources or Information Required but not Available
None yet
Schedule
Risk reduction!
See above comments on it
Energy calculations needed by ~03/14
In time for Troy's birthday
Budget
Spent: $0
Remaining: $1500*
ATA have designated budget may increase IF there is a clear and present need for it (better a finished project with a higher, justified budget, than no project within budget)
Progress on Report and Webpage
Webpage in dire need of filling out. Consider silicone.
Some of the things in Week 10 are technically from Week 9. Consider fixing that!