Modeling and Simulation

OpenRocket, an open-source rocketry software was used to approximate an appropriate stability margin dependent on Jimmy's chosen flight parameters. The software employs Barrowman equations to find the center of pressure (CP) and center of gravity (CG), and motors configurations are implemented to estimate the height, speed, aerodynamic coefficients of a rocket model.

Once Jimmy's was simulated, the model was then emulated inside SolidWorks.

Fabrication

The fabrication process began with phenolic tubing (the airframe), a aluminum-tipped fiberglass nosecone, and 1/4" birch ply (fins). 

A initial cylindrical fiberglass wrap was performed around the phenolic with fiberglass cloth and slow setting epoxy resin. Then, fins were laser cut according to specifications, and tip-to-tip fiberglass layup was subsequently performed for maximum rigidity.

Once Jimmy's frame was sanded, painted, and sealed, it was time to construct an avionics stack. Jimmy's particular Avionics stack is a 3D printed multilayer pyrotechnic bay which is optimized for space management. 

Testing

After modeling, and printing the model, it's time to make loud noises. Ejection testing using black powder is done in a controlled environment. To approximate the amount of black powder needed for a proper ejection, we can rearrange the ideal gas law to calculate the mass of black powder. Several subsequent ejection tests were performed to help determine the exact amount and ensure calibration of the flight computer.

Tools: OpenRocket, SolidWorks, MissleWorks Data Aqcuistion and Configurations Software (mDACS), Ultimaker Cura

Results