Rocket

May 2021 ECE102

Developers: Kenta Taniguchi, John Lindner, Matthew Hopta, Lund Johnson, Jake Delbert, Summer Hall

The purpose of this project was to design a rocket to launch and land safely with a delicate cargo, an egg. We designed the rocket with a teardrop-shaped nose cone containing polyurethane foam to carry the cargo, four fins for stability, and a parachute that deploys at the peak of its flight. The nose cone, fin base, and fins were 3D-printed and composed of ABS plastic, and they were designed to fit in a BT-80 body tube from Apogee.

Our Experience

On the rocket’s first launch, insufficient engine power and wide launch angle made the rocket peak too low for the parachute deploy, resulting in a crash landing.

The nose cone did not protect the cargo well due to the parachute not deploying. Since it was designed for a slower descent rather than a nosedive.

After the launch we found that the C6-3 motor was tough to remove from the motor mount. The motor mount was broken to pull the motor out.

We Recommend

• Larger launch plate for a more stable launch surface
• Inner lip/ledge on nose cone ½ for more secure connection without shifting
• Engine hooks for easy removal

Modifying the motor mount

• To hold two C6-3 engines or a stronger engine
• Block off upper opening to prevent ejection charge from gassing out of the bottom
• A tapered design to pull the engine out with ease

Body

• Apogee BT-80 tube

3-D Printed Components and their Files

• Nose Cone
• Fins
• Motor Mount
• ABS 3-D printing filament

Padding

• Polyurethane sponge (we used a dollar store car wash sponge, though we add an Amazon link)

Parachute

• Nylon fabric
• Twine/String

Motor

• C6-3 engine

Launch

We were provided with a launch pad and controller by our professor, so I provided what I believe is affordable

• Launch Pad
• Controller
• Car Battery

Cargo

• Egg
• Plastic wrap or Ziploc bag

Below are the provided SLDPRT files for 3-D printing.

What we chose to do was to print it in the smallest size it could to reduce as much weight as we could.

Below are the STL files for the motor mount.

We suggest that you wrap tape around the motor to have a better fit but be aware that when the motor is lit it may expand.

About 2-3 wrap around of tape (we used blue tape) would be the best fit.

The sponged should be cut into two nose cone halves.

An egg size crater should be made on the flat side. The depth of that cut out should be half of the egg on each side.

Then the padding should be pasted to the nose cone.

Cut parachute according to the pictures

• Each flat end of the hexagon should be 24 inches apart
• The rectangle edges are gonna be folded in to be sewn

Cut out six 2.5"x2.0" squares

• fold into thirds on the 2.5" side
• Attach to parachute on each of six points

Tie strings according to picture

The motor mount should slide into one side of the tube (This is the bottom of the rocket now, the opposite side is now the top of the rocket).

• The motor mount will need to be taped or glued onto the tube to be secure
• The fins should slide into the motor mount grooves; these too will have to be taped or glued into place

***We recommend before gluing or pasting in the motor mount a layer of tin foil or another flame resistant material should be capped over the end going into the tube with the motor section left uncovered.****

The motor should go into the designated cavity (The circle in the middle of the motor mount)

***We recommend the motor is wrapped in tape to give a snug fit. Though the motor will expand when it is lit. We suggest 2-3 layers of tape***

When the motor mount and motor is in place, through the top some tissue paper or recovery wadding should be put in first before the parachute is put in. (This prevents the parachute from getting damaged by the fuse that deploys it)

The egg should be placed into the padding cavity in the nose cone

• You may want to tape the nose cone shut, just incase the hook unlatches mid flight

The nose cone should slide into the top of the tube.

• The fit of the nose cone should be slightly loose to allow it to separate from the body when the deployment fuse goes off let out the parachute.

1. Place rocket onto launch pad
2. Hook up controller to engine
3. Step back about a yard
4. Press launch button and see it FLY

*** You may need a car battery to get the rocket to fly***