Project Overview
Splash Force was a 2-liter water rocket design project completed under competition-style constraints. The goal was to design, fabricate, calibrate, and test a bottle rocket capable of stable flight, improved altitude, and increased hang time.
The final design used a lightweight parabolic PLA nose cone, clipped-delta fins, added nose ballast, and experimental stability calibration to improve flight behavior. The work combined CAD modeling, MATLAB trajectory simulation, Autodesk CFD visualization, 3D printing, physical calibration, and flight testing.
Recognition
Splash Force received third place in the school-wide water rocket competition. I also received a participation certificate for the project. Both certificates were issued by the College of Engineering and signed by the Dean of the College of Engineering.
The final stabilized design achieved a measured height of 40 m, flight duration of 5.12 s, velocity of 34 m/s, and experimental stability margin of 1.1 calibers.
My Role
I served as team leader for this water-rocket design project. My primary responsibilities included coordinating the final project direction, writing the final design report, developing the MATLAB simulation code, creating the Autodesk CFD simulation work, fabricating the 3D-printed rocket components, and integrating the subsystem work into a complete engineering documentation package.
The project included assigned subsystem responsibilities across stability, fin design, nose cone design, and materials research. I supported the overall design integration by connecting those subsystem inputs into the final CAD, simulation, fabrication, calibration, testing, and reporting workflow.
Team Context
Subsystem Roles
- Team lead and final integration: Jake Cummings
- Stability analysis: Sunday
- Fin design: Ethan
- Nose cone design: Binh
- Materials research: Chris
My Contributions
- Served as team leader
- Wrote the final design report
- Developed the MATLAB projectile-motion and sweep simulation code
- Created the Autodesk CFD simulation work
- Fabricated the 3D-printed nose cone and fin components
- Integrated CAD, simulation, fabrication, calibration, testing, and results into the final documentation package
Technical Summary
The project followed a complete engineering workflow from concept and subsystem research through simulation, fabrication, calibration, and final flight testing.
Aerodynamic Design
The rocket used a parabolic nose cone to reduce drag and improve airflow over the body. The cone was designed as a lightweight PLA shell with tapered wall thickness.
Fin Design
The final fin configuration used a clipped-delta shape selected for stability, bonding area, manufacturability, and drag reduction.
Trajectory Simulation
MATLAB was used to model projectile motion, air-drag behavior, pressure sweep effects, and expected flight trajectories across multiple launch conditions.
CFD Simulation
Autodesk CFD was used to visualize airflow behavior, static pressure distribution, shear stress, and velocity fields around the rocket model.
Design and Fabrication
Nose Cone
- Parabolic geometry selected for low drag
- 3D printed using lightweight PLA filament
- Approximate length: 6.2 in
- Tapered wall thickness from about 0.03 in to 0.02 in
- Designed to support nose ballast for center-of-mass tuning
Fins
- Final shape: clipped delta
- Material: PLA filament
- Designed for bonding surface area and reduced drag
- Final fin area reported as 6.125 in²
- Used to improve static stability and flight direction
Calibration and Stability
Rocket stability was evaluated using center of pressure, center of mass, body diameter, and stability margin in calibers. The report used the standard relationship between center of pressure, center of mass, and body diameter to estimate whether the rocket would be unstable, stable, or overstable.
Center of Pressure
Center of pressure was estimated using a silhouette-based area and centroid method, then compared against the measured center of mass.
Center of Mass
Center of mass was adjusted using ballast added near the nose cone to improve flight stability.
Final Experimental Stability
The final stabilized configuration achieved an experimental stability margin of 1.1 calibers, placing it in the stable range.
Testing Results
Final testing showed improved velocity, altitude, flight duration, and stability compared with the unstabilized prototype.
| Measurement | Unstabilized Prototype | Stabilized Prototype | Percent Change |
|---|---|---|---|
| Velocity | 21.2 m/s | 34 m/s | 61.1% |
| Height | 36.4 m | 40 m | 9.89% |
| Duration | 3.43 s | 5.12 s | 49.3% |
| Stability Margin | N/A | 1.1 Cal | Stable final configuration |
Engineering Challenges
Flight Stability
Maintaining a straight flight path required balancing fin geometry, ballast, center of mass, and center of pressure.
Altimeter Mounting
The altimeter had to be mounted without creating a major imbalance or disrupting the rocket’s stability characteristics.
3D Printing Limitations
Nose cone and fin fabrication required iteration due to print quality, material behavior, and physical fit constraints.
Model-to-Test Gap
Theoretical stability predictions did not perfectly match experimental behavior, so physical calibration and testing were needed to validate the final design.
Development Workflow
Concept and Role Assignment
The team divided responsibilities across stability, fin design, nose cone design, materials research, fabrication, simulation, and final integration.
CAD and Subsystem Design
Nose cone and fin geometry were modeled and revised through multiple design iterations before final fabrication.
Simulation
MATLAB was used for projectile-motion and parameter-sweep simulations, while Autodesk CFD was used to visualize aerodynamic flow behavior.
Fabrication
The final PLA nose cone and fins were sliced, printed, and assembled onto the 2-liter bottle rocket structure.
Calibration and Launch Testing
The final rocket was calibrated using center-of-mass and center-of-pressure measurements, then flight tested to validate stability and performance.
Public Documentation Note
This portfolio page summarizes my contribution and the technical outcome of the project without posting the full original report, team meeting photos, or other materials that include classmates’ images or personal information.
Additional sanitized CAD screenshots, CFD figures, fabrication photos, or launch media can be added later as separate approved portfolio assets.
Related Work / Contact
This project connects to my broader work in mechanical design, simulation, CAD, fabrication, instrumentation, and experimental testing.