Paper airplane engineering

Consider these engineering factors when designing for your Paper airplane:

Accuracy is affected by two classes of cause: internal, and external.

For internal factors, you have:

• consistency of construction/shape, 

• flexibility, 

• wear, 

• changes in material properties due to ink or humidity etc. 

For external factors, you have: 

• Air movements; (many gyms and definitely the convention center in Texas have a lot of airflow)

• friction on the landing surface;

•  launch position, speed and angle;

•  air density vs altitude and temperature. 

• Forces acting on the airplane prior or during launch

From a design perspective you either want to control these factors, or minimize the plane's sensitivity to them. 

Examples:

For consistency in construction/shape, you either want to be very consistent in design and make a shape that you can guarantee at the time of launch (not just before you put it on a robot). Or, you want to choose a design where the location of landing for the drone is more tolerant to changes in shape. This could be a critical consideration if you need to "tune" small control surfaces on the back of the plane.

For flexibility, which can affect flight profile, or could also affect the shape prior to launch, you may want to build a very stiff airplane (unless you find flexible to be of benefit for the flight profile you want.)

For wear, you have to consider how many launches, or straightenings of control surfaces are tolerable before the plane loses its accuracy. A bent nose may not be a significant issue for some designs, but for other designs, it could cause the plane to turn in an undesirable direction.

Ideal Plane (impossible because of conflicting priorities)

The ideal plane would try to achieve all of these things. Rules and physics prevent you from achieving all of these.

• Lightweight to make a smaller launcher

• Heavy/dense to reduce variations due to changes in air movements, also small variations from friction internal to the launcher will have less effect.

• Small surface area to reduce effect of air movements. With zero surface area it would have a purely ballistic and predictable flight profile.

• have a very wide and long mass distribution to increase rotational moments of inertia (make the plane harder to turn). Directional accuracy would be less affected by wind or small turbulence.

• Have a very small and compact mass distribution if the goal is agility to rapidly rotate and dive into the ground.

• Have a flight profile that dives straight into the ground, or better yet, back towards the playing field wall so that other factors don't matter as much.

• Take up lots of space on landing to improve odds of being "in" zone 1

• Be very rigid to protect from changes during the match, or if you are choosing to launch using forces from the back of the airplane. 

• Ideally should launch from the front/under tension because this will tend to align the plane with the center of mass directly behind the source of acceleration. (If launching from behind, make sure your plane has guides both vertically and horizontally).

• Have as much drag as possible with a high launch speed: this will reduce total time in the air and sensitivity to launch speed (rapid deceleration and drop into zone 1)

• Have as little drag as possible to reduce sensitivity to headwind 

• have control surfaces to adjust the flight profile

• Have control surfaces that are very rigid so they never change once set. (or no control surfaces)

You essentially either want a small high density sphere with no ability to bounce or roll, or you want a highly agile plane that can turn around and run into the wall