Engineering Design Challenge 2020

1. ENGINEERING DESIGN
CHALLENGE
Ruhama Atena, Ana Carvalho, Dan Ha, Makayla McLean,
Micah Turner, Haily Vo

2. Our Team

3. Goal of Competition
● Design grappling system attachment for drone (can be 3D printed)
○ Group has decided upon using CAD by Autodesk
● Design objects to be used as payloads
● Evaluate the efficiency of objects that are created

4. Diagnostics
● Familiar Topics:
○ UAVs
○ Balanced force system
○ Newtons
○ FAA registration requirements
○ Quadcopter propeller movement
○ Thrust force
○ Pitch rotation
● Unfamiliar Topics:
○ EDC Eagle ROAR
○ Flight fontrolle
○ Yaw rotation
● Team Average Before EDC: 66.67%
○ 70, 80, 50, 60, 60, 80

5. Competition Context
● What was the motivation for a drone themed EDC?
○ Drones were chosen for this competition mainly because of NASA’s
Mars 2020 Rover Mission. This mission includes finding and
researching signs of ancient microorganisms.
● How do drones generate lift?
○ As the rotor on the drone pushes down on the air, the air pushes up on
it.
● Why do drones use 4 rotors, instead of 3?
○ It is the most efficient way to have an effective drone. The drone is
balanced this way, and it doesn’t start spinning only in one direction.

6. Main Rules
● Drone can not be operated
outdoors (applied before
COVID-19)
● Payloads should be picked up
one at a time by the grappling
attachments on the drones
● Payloads are created using 18
inch wire hangers, and should
be in an uprights position.
● Have to consider certain
restrictions of
measurements of the
drone itself
● Can not modify drone
itself, only adding
attachments
● Cost should be considered
● No adhesives, fasteners, or
strings

7. Technology Used

8. PRELIMINARY WORK

9. Drone Mechanics
Four forces affect all objects in flight, including this drone: lift, thrust,
weight, and drag. The direction the drone flies in is determined by its
pitch, yaw, and roll. Pitch moves the drone forward or backward, yaw
rotates the drone, and roll moves the drone sideways (left or right).
The four motors change speed to achieve these effects. Diagonally,
two rotors move clockwise as the other two rotors move
counterclockwise. This is done to equalize forces between the rotors
on the drone.

10. Flight Techniques and Requirements
These hand motions are communication methods that we learned for
when we flew the drone during competition. This allows for visual
communication from a long distance, so there are no auditory issues.

11. Reference Models
We created reference models in
order to mimic building off the
drone. We used the provided
electronic dial caliper for our
measurements and created the :
➔ Landing Gear
➔ Camera Holder

12. Comparing the
Attachment Points

13. Initial Grapple Design
Initially we thought of the ‘I’
Frame with a free joint hook.
This would eventually change as
we continued through the
season and created a variety of
new ideas.

14. Important Measurements
Camera Mount:

15. PAYLOAD DESIGNS

16. Our Payload Design
Design 1: Pyramid structure
with a loop around the top for
support.
Design 2: Coil structure,
decreasing diameter as it gets
higher for stronger base.
Design 3: Pyramid structure
that runs around the hook for
support

17. Payload Prototypes
Pros: Strong triangular sides,
loop ensures it does not come
apart
Cons: Base is not as steady.
Pros: Strong, steady base;
easy to pick up.
Cons: Hard to fabricate.
Pros: Steadier base than first
pyramid design
Cons: Loop at top can come
undone

18. ATTACHMENT DESIGNS

19. Initial Sketches
Design 1: Documented the beginnings of the
free-joint grapple, where we didn’t have to go to
close to the ground when trying to drop or grab a
payload.
Design 2 (Left): This shows one of
our first attempts at designing a
base that attaches to the drone legs,
avoiding dislodging of parts
midflight.
Design 3 (Right): Static grapple with
an “I” frame, problems with distance
to ground for pick-up and large
amount of volume for frame.

20. Initial Sketches
Design 4 (Left): This idea
incorporates a free joint and a
hook which releases a payload
whenever the movement arm
hits the ground. Whenever the
drone lands, the piece folds
upward as the movement piece
rubs along the ground.
Design 5: Using the idea
of a free joint hook
attached to the legs of the
drone, this grappling
system can be used with
the camera attachment
system on the drone.
Design 6: (Right) A
telescoping mechanism
can be used to allow a
payload to be picked up
from the drone at a greater
altitude while allowing the
drone to land safely.

21. Attachment Method 1
The use of a buckle makes it
very easy to take an attachment
on and off. The only problems
may be keeping track of the
individual pieces and the
clearance needed to bend the
component. The clearance also
has to be enough to where it
doesn’t snap.

22. Attachment Method 2
The clasp is made so that there
is no way for the frame to escape
unless the frame is bent inwards.
There is some room on each
clasp on the outside where this
is possible.

23. Camera Attachment Method
Mounting to the camera
attachment is another viable
option. This would allow for
several different grapple design
ideas to be attached to the drone
here. The problem with this idea
is that the weight distribution
shared with the drone would be
interrupted, causing changes
with the center of gravity,
affecting the stability of the
drone.

24. Attachment Frame 1
Using an elevated ‘I’ frame gives
us enough clearance to attach
our grapple system without it
being initially disrupted by the
ground and payload.
Also Preliminary
Design →

25. Attachment Frame 2
The elevated ‘X’ achieves the
same purpose of the ‘I’ but less
volume needs to be used in
order to achieve that purpose.
Both the X and I are able to use
both attachment methods for the
landing gears.
Also Preliminary
Design →

26. Grapple Design 1
The static grapple is attached to
the bottom of our frame.
However, because this grapple
cannot extend the height of the
landing legs, we have to fly very
close to the ground to align it
with the payload. The use of
supports will help the static
grapple be more secure.

27. Grapple Design 2
The free-jointed hook allows for
more tolerance in height as the
hook isn’t static so it will not
clash with contrainted height.
We also do not have to fly the
drone as close to the ground as
it will extend the height it is able
to pick up a payload.

28. POSSIBLE ASSEMBLIES

29. Assembly 1
Clasp + X-Frame + Free-Joint
Hook
Cost: $25 x 7.947 g / 1000
= $0.20

30. Assembly 2
Buckle + X-Frame + Static
Grapple
Cost: $25 x 5.709 g / 1000
= $0.14

31. Assembly 3
Camera Holder + I-Beam+
Free-Joint Hook
Cost: $25 x 5.006 g / 1000
= $0.13

32. Assembly 4
Camera Attachment + I-Beam +
Static Grapple
Cost: $25 x 4.279 g / 1000
= $0.11

33. Comparisons
Assembly 1: Assembly 2:
Assembly 3: Assembly 4:
Cost:
$0.14
Cost:
$0.13
Cost:
$0.11
Cost:
$0.20

34. FINAL DESIGN

35. Final Design
The “Anchor” design uses a
T-beam for structural support
while incorporating a double
grapple design. The design
attaches to the camera
attachment point on the drone to
utilize official drone attachment
points efficiently.
Cost: $25 x 5.602 g / 1000
= $0.14

36. Final Design

37. Future Considerations
● Pursue different design concepts with different advantages and
disadvantages
● Test designs or assemblies by 3D-printing
● Experiment with constraints of the drone (center of gravity,
performance)
● Consider flight experience into the design process
● Invest more time into the payload design process

38. Challenges and Obstacles
● COVID-19
● Lack of access to dimensions of the drone in order to build off of
our attachment points
● Inability to test or prototype designs and assemblies
● Communication
● Micah’s handwriting

39. Reflections
● Grasped a better idea of how exactly a drone works
● Experienced the engineering design process as a team even
with a virtual setting
● Learned a lot about CAD software
● Learned forklift signals for communication from long
distances
● Learned basic operations on how to fly a drone

40. Thank You for Joining Us
special thanks to,
Ms. Ewbank, Ms. Talbert and
Mr. Caruso