Team Vision for Detailed Design Phase
What did your team plan to do during this phase?
- Continue analyzing data from test, especially high speed video.
- Find new solutions to minimizing damage to windows
- Begin design of experiments and associated equipment for testing in MSD II
What did your team actually accomplish during this phase?
- Finish analyzing high speed data and condensed values into single table
- Continued research on solutions to window damage
- Preliminary test designs completed and test fixtures designed
Progress ReportSummary of the Teams Work To Date
- Finished analysis of the videos from the high speed cameras
- Research on potential testing and have a proposed plan for small scale testing
- Review of teams goals for the semester and for the start of next year
- Prelim. Notes & Action Items PDF have the notes and the action items the team focused on
Engineering & Data Analysis
- Location 1 feels the most blast force
- Baselines for small scale testing gathered
- Displacement wave travels at speed of sound (~340m/s)
- Not enough usable data to draw conclusion about windows up/down
Prior to beginning testing at location 3, our high speed photography expert, Dr. Kinsman, had to leave. We attempted to use the high speed function on our phones but the results were lackluster.
Excel files for each test can be found here
Video files can be found here
Proposed Drawings, Schematics, & Prototypes
The images below show our intended design for the fixture that will be used to hold the window sashes during testing.
The window will be held in place with the bolts in the corners.
A vacuum hose can be attached to negative pressure, replicating the affects of the pressure from the cannon blast.
Test Fixture Bill of Material (BOM)
To build our testing rigs, we will need the following materials:
- 2 x (7/16" x 4' x 8') Plywood Boards
- 3 x (8' x 2" x 4") Studs
- 2 x Silicone sealant
- Misc Hardware (machine shop provided)
- Shop Vac (machine shop provided)
Current Total: $45.46 (subject to increase)
Current Test Plans
PurposeMeet Engineering Requirements 1,2, and 5.
- ER1: Maintain sound level for spectators
- ER2: Measure current damage
- ER5: Keep sound level below damage level
Proposed Procedure - Low Frequency Fatigue Testing
- Determine peak low range frequencies of cannon fire
- Build test rig as shown
- Use speakers to determine resonant frequency of Sash/glass
- Compare results and look for similarities
- Replicate frequencies to load windows ( in accordance to displacement data collected during testing)
- Repeat cyclical loading until window shows increased damage or failure.
- Ability to conclude if the low pressure frequency waves are the primary cause of the damage
- Estimate for window life measured in number of cannon firings
Design and Flowcharts
Process Design FlowchartThis chart shows the ideal organization of the process documentation we are working on. Red boxes indicate inputs from GCVM staff, yellow boxes are the documents themselves, and blue boxes show the outputs of the process itself. Note that yellow process documents work together to turn input data into desirable outputs.
- Updated assessment from Preliminary Detailed Design or link to other location. Have you driven the likelihood and/or severity down as you worked through the details of your design?
Design Review Materials
- Pre-read was not sent for this phase due to the meeting being rescheduled several times prior to start
- EDGE page was presented during the Detailed Design Review
- Notes & Action Items will be linked here after the review
Plans for Next PhaseThere are three main parts that will make up the next phase for our team:
- Test Plan, Preparation, & Budget
- Additional Data Collection
- Solution Implementation
Test Plan, Preparation, & BudgetWindow sashes will be tested for fatigue and cracking, as well as testing the plaster. The focus on small scale testing is to ensure we identify the causes of damage to the windows and plaster prior to the Civil War Reenactment.
In order to accomplish this, our team will need to:
- Purchase needed items for test fixture
- Construct the test fixture
- Develop a test plan and accurately mimic the effect of a cannon blast
- Conduct tests and record data
- Analyze data
- Prepare for another onsite test with results in mind
Additional Data CollectionTeam has looked into other reenactments and artillery demonstrations for cannon recording. This is due to Reynolds Battery having their cannons put away for winter storage so we are exploring alternate options before April. Below is a map of potential reenactments and demonstrations our team could try to attend.
Solution ImplementationThe end goal for our team is to create a list of potential solutions for GCVM to implement. This includes but is not limited to: damage reports & documents, sound damping options, and vibration mitigation. With these in hand, GCVM can be advised on best practices to help reduce damage to the historic buildings.
For MSD II, a Project Timeline for Spring 2019 is in the works for planning our next steps. More will be added as the weeks go on and generally will be kept flexible due to the nature of this project being research and result based.