2016 Technology Challenge Report
Academy of
Arts, Careers, & Technology
NASA Rover
Team
University
of Nevada Advisors: Dan Ruby
AACT
Faculty Advisors: Greg Burge, Jim Cooney, Addison Wilhite
Tech. Design, Safety, and Media: Natalie Fox, Emily Contreras-Johnson, Kimberly
Aguilar, Katrina Dutt, Lori Berg, Shannon Palmer, Irene De Haan
CAD Team: Preston
Latham, Dexter Bush, Owen Schenk
Fabrication
Team: Dexter Bush, Travis Troop, Patrick Thompson, Kraigon
Ladner, Preston Latham, Christian Oaks, Gregg Symonds, Natalie Fox, Alissa
Chavalithumrong, Jordan Buxton, James Harney, Miranda Weinert, Cory Starks,
Irene De Haan, Grace Wallace, Anthony Sombatoiri, Kimberly Aguilar, Sarahann Wallace,
Katrina Dutt, Turbo Sombatsiri, Lorenzo Arvisu, Henry Day
Away Team: Dexter
Bush, Madelyn Newcombe, Owen Schenk, Christian Oaks, Irene De Haan, Natalie Fox
3 Technology Challenge
3.1 This
Year’s Challenge
3.1.1 Technology Challenge Definition
The engineering designs from NASA are mainly focused on plans
to explore planets, moons, asteroids and comets. Designing, constructing, and testing mobility
technologies to perform in different obstacle courses are the main focuses for
the NASA Human Exploration Challenge.
Each rover must be human powered and be driven by two students, one male
and one female. Each year there is a
different challenge provided by NASA for the teams to solve.
3.1.2 2016 Challenges
The challenge for the year of 2016 consists of each rover
being human powered, building a custom wheel for the rover, and changing a
minimum of 50 percent of the combined total structure and systems.
Each team must design and build their own wheels. The only commercial items that can be used in
the fabrication of this rover are the hubs containing bearings or bushings. The
wheels should include the outer surface and a supporting structure.
There also must be change of a minimum of 50 percent of the
combined total structure and systems if the rover is being reused. A reused vehicle is considered a vehicle that
has been registered in competitions and participated in a race in previous
years. Adding new content or changing
existing pieces qualify as a change.
3.2 AACT Rover Team Solutions
The AACT
Rover Team addressed these challenges by designing and fabricating a new wheel
and changing a minimum of 50% of the rover.
As a team,
we have decided to come up with a new wheel design. This year, we decided to machine our own hub
along with a new tread and supporting structure.
For the
minimum change of 50 percent, the AACT Rover Team has determined to completely
redesign and fabricate new wheels, crew restraints, storage systems, and
vehicle braking.
3.2.1 Wheel
Design
For the 2016
NASA Human Exploration Challenge, the team has decided to completely redesign
and fabricate new wheels. The design
process began with our students Dexter Bush, Owen Schenk, and Preston Latham trying
to come up with a lighter wheel design that included a machined hub. They had to redo the original drawing eight
times in order to get it perfect. It was
agreed upon that the ninth design was the best option, which included the
dimple die idea. It was decided that the
best material for the wheel to be made out of was aluminum because it would
make the wheel much lighter than previous years’ designs. This year’s wheels will be made out of 1/8”
aluminum, which makes the overall weight of each of the wheels 5 pounds lighter
than last year’s design.
3.2.2 Building
the Wheel
To build
this wheel, the AACT Rover build team began by cutting the 1/8” aluminum into
2ft by 2ft squares. They put these squares into the plasma cutter to cut the
holes for the dimple dyes and proceeded to dimple die these holes. The team
then bolted these to the jig and cut the outsides. They used the CNC machine to make the hubs
and installed pins onto the hubs. Then,
the team bent the L angle into a circle to create the rims, plasma cut and
rolled the outside strip. The team proceeded
to assemble the wheels and welded the parts together using the tig machines.
The team cut and drilled the suction hose and installed these tubes onto the
cabling on the wheels. The final step in
this process was to rivet down the tread material.
3.2.3 Returning
Vehicle Requirements
The 2016 NASA
Human Exploration Challenge requires each returning rover to have at minimum a
50% change. The AACT Rover team
addressed this challenge by changing the wheels, crew restraints, storage and
deployment systems, and vehicle braking.
The newly
designed and fabricated wheel counts as a 10 percent change for each
wheel. In total, we have 4 new wheels,
which qualify as a 40 percent change.
The next
part that the team changed is the crew restraints. The team determined to
change these restraints to ensure the safety of our drivers. This counts as a
10 percent change.
3.3 Machining the Hubs
3.3.1 Deciding
to Machine Our Own Hubs
For the 2016
Rover Challenge, it was optional to create your own hubs; however the AACT
Rover team decided to take on this challenge.
Our team concluded that this was the best solution because we could not
attach them to our old Chub Hub. We
would have had to use bolts to connect these parts together, but we concluded
that it would be best to machine the hubs so that we could weld directly onto
them.
3.3.2 Creating
the Hubs
The process of
fabricating these hubs was not too difficult; however, it was time
consuming. The team began by using the
CNC lathe to machine the aluminum. This
created the inside and outside diameters.
They then used the CNC mill to make pinholes and tap them. The team finished the hubs by using the
opposite side end mill to machine the swirl pattern.
AACT Fabricated Hubs
3.4 Precautions and Durability
3.4.1 Problems
We Encountered and Our Solutions
There were a
few design issues that we encountered while we worked on this project. One of
the main design flaws we had was when the spokes were welded, they warped and
got out of true. To solve this problem,
we welded them in a truing stand.
Another problem that the team encountered was when we dimpled the
spokes, the plate warped six (6) inches. Our solution was to build a custom steel jig,
bolted it down, and then cut around the jig. The final major problem we came
across was the tubing. For the 2016
year, the team decided to use a cable to keep the tubing in place, rather than
last year’s rivets. In order to keep this tubing in place, the team needed to
create cable guides to keep the tubes in place.
3.4.2 Design
Features That Ensure Success in the Race
The main
design feature that was created to ensure success in the race was the dimple
dyes. The spokes were dimple dyed to add strength. They add sideways, up, and
down strength. Another design feature
that was created to ensure success were the tubes. The tubes provide suspension
for our rover as it rolls over obstacles.
Dimple Dying the Wheels
3.4.3 Most
Likely to Break
Early
prototype testing revealed that the part that is most likely to break on our
2016 rover are the tubes. If one of the tubes break, all of the tubes could
break. We tried to prepare for this
problem by creating a cable system to hold them in place. In order to keep the cables in place, we made
tabs on the side of the rims to ensure that the tubing and cables would stay in
place.
Cable Alignment Tabs
3.4.4 Precautions
The 2016
AACT Rover team took a few precautions with our vehicle. One precaution that we decided to take is
that we made one area thicker where it will be welded. This made it stronger so that it would not
warp during the welding process.
Another
precaution the team took was to create a large surface area to ensure the
strength and durability of the wheel. We
discovered that if there was too much tension on the wheels, they could
bend. With the larger surface area, the
wheels will be less likely to bend.
Close Up of the AACT
Rover Wheel Design
3.4.5 Making
the Rover Lighter
We decided
to make the rover lighter by eliminating large amounts of weight from the
wheels. We realized that the wheels
would be the best place to take weight from due to the difficulty in pedaling
in previous years. The wheels in
previous years were wider and created more friction.
To make the
wheels lighter, the team used much less hardware. We welded the wheel together rather than
bolting it together as we have in previous years. The team also used the cable tensioning
method, which takes one cable through all hoses with a turnbuckle for
tensioning. This allowed us to remove
the heavy rubber belting that took up space.
In total, each of our wheels were 20 pounds lighter than in 2015.
AACT Rover Wheel
3.5 Costs and Materials
Materials paid for by Nevada Space Grant
Consortium (NSCG) and Washoe County School District (WCSD)
|
Cost
|
Material
|
Amount
for Set
|
Paid
By
|
|
$47
|
1/8” Plastic Covered Stainless Steel
|
100’
|
NSCG
|
|
$26.20
|
1/4” Eyelet Turnbuckle
|
5
|
NSCG
|
|
$19.97
|
Swaging Tool
|
1
|
WCSD
|
|
$14.8
|
1/8” Aluminum Ferrule and Stop Set
|
10
|
WCSD
|
|
$8
|
SWM Bolts
|
1 pack
|
NSCG
|
|
$250
|
Sprocket
|
10
|
NSCG
|
|
$10
|
Cable Noodles
|
10
|
NSCG
|
3.6 Locations
For this
challenge, the AACT Rover Team used a few locations to construct our
rover. We mainly used the Truckee
Meadows Community College’s campus for our meetings. We used this campus’ workshop to build,
machine, and weld our rover. We also
used the Academy of Arts, Careers, and Technology’s campus, located across the
street from TMCC, to use the computers for writing and drafting. We also used AACT’s bike shop and parking lot
to train our athletes.
3.7 Lessons Learned
During the
process of building this NASA Rover, our team learned many valuable life
lessons. We learned the value of time
management through real-life deadlines.
We learned how to accomplish tasks without having to stress over the
time. Another lesson that we learned
during this challenge was how to work together as a team. Each team member had to communicate with each
other in order to create this rover, which required patience and listening abilities. Every one of us had our own ideas on how we
should create this rover and we all needed to work together to create one
functioning rover.
The most
important lesson we learned was how to function as not only a team, but a
family. We learned how to treat everyone with equal respect. This challenge taught us how to function as
an engineering team in ways that we had not done previously to ensure a working
rover.
2016 AACT Rover Team
