Structure Detailed Design
Table of Contents
Drawings, Schematics, Flow Charts, Simulations
Platform CAD and Layout
The platform design was developed further to include the board layout and methods for securing the the insulation and solar panels. The top aluminum sheet will be used to secure the solar panel as well as attach the balloon and housing for all of the components. The final weight of the structure is about 2.5 lbs.
Platform FEA Analysis
FEA analysis was performed to simulate the weight of the components on the platform. The loads included gravity acting on the structure as well as the weight of the components. A minimum factor of safety limit of 2 was set. The simulation resulted in a minimum factor of safety of 3.5 and maximum displacement of 1 mm at the center of the housing.
The simulation below represents the displacement of the structure during flight. The max displacement is about 1 mm and occurs in the middle of the structure due to the weight of the components. This displacement can be reduced by extending the housing supports.
The simulation below represents the stress on the structure during flight. The housing supports undergoe the most stress but remain substantially below the yield point
After further design optimization, the weight of the structure weight was reduced to 2.5 lbs. Because of this reduction, the total weight HABIP is now estimated to be 10.5 lbs. This is below the 12 lb limit.
Bill of Material (BOM)
ER10: Component Operating Temperature
The goal of this test is to validate that all components in the structure remain at a safe operating temperature. This minimum temperature is 0 degrees celsius which is the minimum charging temperature for the battery. Power estimates will be made for each component and a simulation will be developed in SolidWorks.
ER12: Structure Attitude Control
FEA analysis can be performed to simulate the force on the platform due to the reaction wheel. The Factor of Safety must still meet the minimum requirement of 2. After this factor of safety is validated, a prototype platform will be built to mount the reaction wheel and components. The reaction wheel data will be recorded and analyzed to confirm rotation requirement is met and components remain secured to the platform.