Week 0 Introduction

Airplane float

Design a rubber band airplane which will float in the air for 30 seconds

Week 1 Narrative

Tasks:

Design testing protocol for airplane float tests
Create Center-of-Gravity test from p1w4

Doing:

Testing Protocol V1

Testing will be done as follows:

Find open area with no obstructions and minimal wind.
Twist propeller in opposite direction of its natural spin 100 times to tighten rubber band.
Hold plane 6 feet above ground in hands, making sure propeller doesn't start yet.
Before throwing, let propeller start spinning.
Throw plane by moving hand forward around 4".
Use stopwatch to count how many seconds the plane stays in the air.
Record other notes (nosedives, heavy tails, any propeller issues, etc.).
Repeat test 5 times per model to make sure numbers are repeatable.

Center of Gravity Test V1

Testing is done with 5.25" computer drive bay (Dimensions: 5 3/4" * 3/8" * 1 5/8")

Place model plane on top of drive bay.
Adjust plane until it stays balanced on top of the drive bay.
Mark point where plane stays balanced.
Place front wing centered on top of mark.

If propeller is too big, hang front end off of a table.

Using the balance prop (5.25" drive bay), the Center of Gravity can be found very simply.
Close-up on the balance prop.

Next Steps:

Use Center of Gravity test in the making of next plane model (place front wing in optimal position).
Test next plane model with new test protocol and compare results to older, less organized tests.
After making multiple more models, compare performance and suggest design changes based on new testing protocol.

Week 2 Narrative

Tasks:

Build a longer, narrower wing (higher aspect ratio)

Doing:

Testing Protocol V2

Testing will be done as follows:

Find open area, preferably inside where wind is not a factor.
Twist propeller in opposite direction of its natural spin 100 times to tighten rubber band.
Hold plane 6 feet above ground in hands, making sure propeller doesn't start yet.
Before throwing, let propeller start spinning for 3 seconds.
Throw plane by moving hand forward around 4".
Use stopwatch to time how many seconds the plane stays in the air.
Record other notes (nosedives, heavy tails, any propeller issues, etc.).
Repeat test 5 times per model to make sure numbers are repeatable.

This Wikipedia page explains why a longer, higher AR wing can help gliders. Basically, a wing has the effect of a cylinder of air, with the diameter being the wingspan. If the wingspan is longer, with the same width, the amount of air the wing pushes downward is greater than with the shorter wingspan.

Making High AR Wing

Materials needed:

Plastic wrap
Wooden coffee stirrers
Glue/adhesive (used Duco Cement)

Steps:

Lay out plastic wrap over workspace.
Take 2 coffee stirrers to act as the middle two sticks going long-ways and place adhesive on tips.
Place the 4 coffee stirrers on each tip going long-ways.
Cut 2 coffee stirrers in half.
Glue 2 of the halves to the ends of the outer coffee stirrers to connect the lengths together.
Take the wing lengths and mark at 1/4 of the length and 3/4 of the wing.
Place the last two halves under the 1/4 mark and the 3/4 mark of the lengths. These act as ribs to make the wing more sturdy in crashes.
Flip wing over.
Wrap plastic wrap around the finished wing tight.

Finished wing. Dimensions: 19.5 in. x 3.5 in.; Aspect Ratio: 2.79

Next Steps:

Attach wing to the fuselage.
Record data of flights with this wing.
Compare data to flights with wings teammates made.

Week 3 Narrative

Tasks:

Finish making model using wing from Project 2 Week 2
Place model through testing protocol

Doing:

The coffee stirrers are wooden sticks with a length of 6.875 inches and a width of 0.1875 inches.

Horizontal stabilizer was made using 1 coffee stirrer for length and 1/3 a stirrer for the width.

Dimensions for the horizontal stabilizer: 6.875 in. x 2.292 in. Wrapped in plastic wrap in the same way that the wings in Project 2 Week 2

Attached horizontal stabilizer to the fuselage (Dimensions: 10 in. x 0.125 in.). Found and marked center of gravity on fuselage. Placed wing slightly in front of center of gravity.

Low Aspect Ratio (abbreviated AR) Test Flight

Wingspan: 19.5 in.

Body Length: 10 in.

Weight: 12.8g

Average flight: 0.8 seconds

Flight notes: Definitely tail-heavy. Stalled or backflipped on every throw.

Picture is for size comparison between plane and metal coil

After noticing this, I placed a coiled spring on the front for weight. I used a pen cap as a temporary way to keep spring on.

Low AR Test Flight With Coil

Weight with coiled spring: 19.2g

Average flight: 1 second

Flight notes: Flew straight. No flips. Descended quickly though. Maybe too front-heavy, but better than stalling.

Though not recorded in numbers, the plane with the coil on the front tends to fly longer when thrown harder. Consider revising test protocols?

Next Steps:

PRIORITY: Find out how to make elevators for wing (to compensate for a slightly front-heavy plane)
Revise test protocols referring to plane launch (how to define a harder throw)
Change wing shape to increase lift?

Week 4 Narrative

Tasks:

Wrapping up Airplane Float project
Becoming familiar with new project
Creating goals for new project

Doing:

Correct Theory of Lift

Incorrect Theory of Lift

As far as the Airplane Float, found that lift is generated by the turning of a moving fluid, in this case the air. The wings have a slightly asymmetric top and bottom, and the camber (shape of the wing) points down slightly at the aft-end. Along with this, I reasoned that our group's flat-wing designs, even with polyhedral wings (wings that change angle more than once on the wingspan), would need much more velocity to produce any lift. Considered different options for changing the wing camber while using the same materials. Then, the project got disbanded.

Wing profile nomenclature. Picture shows the slight downward angle at the aft end of the wing.

Puttputt Golf

Tasks:

Look at creative ideas used by past HCC puttputt projects.

Doing:

This is the only project page I found. This group designed a pendulum obstacle for a mini golf hole. The motor for the pendulum was created using an Inkjet printer motor programmed with an Ardrino Uno and an ADA-Fruit motor shield. No pictures or video to show for it.

Goal: Use Arduinos to control motors in obstacles to make an interesting mini golf hole. The actual hole is going to be created.

Next:

Find an Arduino and a motor shield to start experimenting with.
Design 1-2 obstacles to be controlled. (How they move superficially; how the machine will be made on the inside.)
Look through these projects
Look through these projects