Rocket Technical Design

This project covers my technical contributions to the 2018-2019 Washington State University Aerospace Club.

Author

Jonathan Cochran

Background

• Testing rocket the club built to attempt a new air brake system
• An air brake controls ascent of rocket by increasing drag with a feedback algorithm

Directory

• Velocity Simulation: simulate rocket trajectory based on CFD analysis values and motor specifications
• Recovery Ejection: ejection calculations for deploying parachute recovery system
• Static Simulation: static simulations to characterize forces on rocket body when air brake closed/deployed
• Electronics Bay Design: carved wood bay to contain electronics module and fit within rocket tube

Velocity Simulation

• MATLAB simulation to model trajectory (velocity_sim.m)
• Modeled drag as a function of velocity, thrust as a function of time for motor, and mass loss as a function of time from motor

Recovery Ejection

• Calculated grams of black powder necessary to eject a parachute from the top of the rocket
• Must not over-estimate or structure stability could be compromised

Static Simulation

• Static study in SolidWorks Simulations to examine the force applied to rocket body when air brake is fully closed and extended
• Evaluated at top speed of 1100 ft/s and at the speed off launch rail of 65 ft/s
• Applied an orthogonal fiberglass-epoxy resin material to the body tubes
  • Values for this material derived from performance-composites E-glass Fabric
  • Applied 0° values for Y direction and the 90° values for X and Z directions
    • X and Z are perpendicular to the Y direction so they will have the same values with reference to the Y direction
• Top Speed (1100 ft/s)
  • Extended: 76.38N
  • Closed: 65.97N
• Speed off rail (65 ft/s)
  • Extended: 4.89N
  • Closed: 3.96N

Electronics Bay Design

• Designed an electronics bay to hold electronics module
• Fits inner diameter of rocket tube
• Holes in bottom for wires to feed through
• Fastener locations for securing electronics board to the bay
• Raised edges for holding additional electronics equipment
• Manufacturing consideration is for wood to be cut and placed in manner presented
  • Fastening mechanisms were glue, screws, and friction

Isometric View

Bottom View

Side View

Top View

Mount View

Acknowledgment

Thank you to WSU Aerospace for the experience!