Preliminary Detailed Design
Team Vision for Preliminary Detailed Design Phase
- What did your team plan to do during this phase?
During this Phase the team plans on continuing the design laid out in the previous phase. The Feasibility needs to be completed which will confirm on paper that this system will work. In addition prototyping of the diaphragm material will be started to confirm that the material being used will work in our situation.
- What did your team actually accomplish during this phase?
During this phase, the team learned about the feasibility of our design. We used Solidworks finite element analysis to model the diaphragm and determine a suitable diameter and operating pressure. In addition we ran hand calculations to determine a magnet needed to complete the design. The team received free samples of Kapton material and ordered magnets for testing.
Prototyping, Engineering Analysis, Simulation
The Team has used engineering software including SolidWorks to develop a Finite Element Analysis simulation of the diaphragm. This is important because it tells us where the greatest stresses are on the diaphragm and helps to better design the system.
For the Magnets, the team has worked to determine a size and strength magnet that will be needed to hold the system in place. This was determined using data from a magnet supplier.
The modeling takes into effect the use cases of the pressure sensor, in which it will either reach the desired pressure and activate the switch, or not activate if the desired pressure is never reached.
Feasibility: Prototyping, Analysis, Simulation
Initially, we were using National Lab's thin plate theory to determine how the diaphragm would act during operation, but this approach didn't characterize enough of the motion of the diaphragm during operation so we instead used simulation to understand the operating conditions of our diaphragm. Using the simulation available in SolidWorks we ran a Finite Element Analysis (FEA) on our diaphragm to better understand how the diaphragm would act in test conditions as well as providing us with additional information compared to thin plate theory calculations.
Below is the FEA result of the simulation run with a 3/4" in diameter diaphragm.
Below is a table of max center deflection for various diaphragm diameters
|Diameter (in)||Max deflection (in)|
To do initial testing for diaphragms we assembled a test setup (see below) to pressurize one side of the diaphragm to simulate operating conditions.
The pressure gauge and regulator combo allowed us to have more control over the pressurizing of the diaphragm.
This sample housing for the test setup allows us to test various diaphragm materials quickly since there is easy access to the diaphragm.
Drawings, Schematics, Flow Charts, Simulations
Bill of Materials (BOM)
The switch will be tested in the Hitachi HUS-5GB High Vacuum Evaporator. The manual for the evaporator and the inspection/safety/testing documents procedures are contained in the files below:
Design and Flowcharts
- Updated assessment from Subsystems Design. Have you driven the likelihood and/or severity down as you worked through the details of your design?
Design Review Materials
Plans for next phase
- As a team, where do you want to be in three weeks at your next review?
By the next review our plan is to bring forth a completed design with proof of concept, prototype analysis and relevant data that will be fabricated during Senior Design 2. We will have a BOM stating all the parts for purchase, drawings created, and test plans for how to properly test the system.
- As an individual on the team, what are you doing to help your team achieve these goals? (Use the individual 3-week plan template for this)