Upload
others
View
0
Download
0
Embed Size (px)
Citation preview
SEAN M. REIDY
1024 Conception Drive • Lompoc, CA 93436 240-478-4734 • [email protected] • http://seanmreidy.com
INTRODUCTION
My name is Sean Reidy. I'm 26 years old and grew up in
Montgomery County, Maryland and am currently a Launch
Engineer for SpaceX in Southern California. I'm working to
launch things, and eventually humans, into space. My current
responsibilities include launch operations and automation out
of Vandenberg AFB and Cape Canaveral AFS, as well as
automating the launch integration process.
I earned my bachelors of science in Mechanical Engineering
from the University of Pennsylvania in 2015 with a minor in
Computer Science. I hold a deep interest in mechanical
systems and robotics, inspired by my work in Penn's General
Robotics, Automation, Sensing, and Perception (GRASP)
laboratory. There I used and even modified 3D printers to
explore new manufacturing possibilities. My involvement in
Penn's graduate-level Design of Mechatronic Systems class
solidified my interest in robotics. I want to leverage
mechanical design, electronics design and computer science to
work with complicated systems.
In summer 2014, as an intern at The Boeing Company, I
worked in the Scripted Process Engineering team where I
wrote code in Python to automate the manufacturing process
for composite material panels used in the construction of new
Boeing 787 and 777X aircraft.
At Penn I served as a teaching assistant for the Introduction to
Computer Science class for three years, where I held weekly
recitation sessions and office hours to help students learn
programming. I also served as President of the Penn chapter
of the American Society of Mechanical Engineers, and was
actively involved in Theta Tau Professional Engineering
Fraternity and Alpha Chi Rho Fraternity.
I have made an effort to diversify my skills across the
mechanical engineering and computer science disciplines. I
have refined my skills in mechanical design by learning and
mastering the SolidWorks application on my project work
over the last three years. I have worked with MATLAB for
data analysis and expanded my coding skills by developing
expertise across a variety of programming languages including
C, C++, Java, Python, and PHP. I also designed electronic
circuitry and hand-soldered circuit boards for all my projects.
The following pages present a sampling of project work that
showcases a broad spectrum of the skills and experience I
have developed at Penn, not so much a summary of my
current professional work, which is mostly ITAR protected. If
you would like to see more of my projects, please visit my
website at http://seanmreidy.com.
Me on top of Mount Si, around 30 miles
from Seattle, WA.
SpaceX (2015-Present)
The Boeing Company (Summer 2014)
General Robotics, Automation, Sensing
and Perception Laboratory (2013-2014)
National Institute of Standards and
Technology (Summer 2012)
SEAN M. REIDY
1024 Conception Drive • Lompoc, CA 93436 240-478-4734 • [email protected] • http://seanmreidy.com
BREAZE
MEAM 446 – Mechanical Engineering Senior Design
September 2014 – April 2015
Collaborators: Shelby Bierig, Lars-Patrik Roeller, Noah Frick
OVERVIEW
Breaze is a portable, autonomous solution to oxygen tank
transport for the purpose of supplemental oxygen therapy. A
variety of ailments require continuous oxygen supply such as
chronic obstructive pulmonary disease, late-stage heart failure,
cystic fibrosis, and pneumonia. As elderly patients travel
within the hospital, they often require nursing assistance to
carry their oxygen tanks which discourages them from
maintaining their physical therapy.
TECHNICAL APPROACHES
Breaze is a robotic retrofit for oxygen tanks which can follow
patients around in a hospital setting, eliminating the need for
manual transport or nursing assistance. The device is powered
by DC motors and can change directions with the patient, as
well as avoid obstacles in its path. By implementing robotic
control and path-planning algorithms, Breaze will track
patients and maintain a proper distance, making mobility more
feasible and less of a burden. To meet the demands of an
aging population, Breaze increases the quality of life for
patients by promoting mobility and incentivizing consistent
oxygen therapy.
The user wears a "beacon" belt pack, with one ultrasonic
Parallax transmitter and an RF receiver to sync the time
signal. The vehicle contains three spaced ultrasonic Parallax
sensors which pick up the signal from the beacon. The vehicle
transmits a packet via RF to the beacon, and proceeds to wait
for the signal from the ultrasonic transmitter. Upon recording
the time taken to receive the signal from the beacon, the
vehicle triangulates the relative position (distance and
orientation) from the user. Because we have three holonomic
constraints, we can determing planar x-y relative position, so
the height of the user is irrelevant.
After gathering location information, the control algorithm
uses a PD-based controller to correct the vehicle to "zero-in"
on the user, as well as maintain a 1-meter distance from the
user, and is capable of smooth correction up to 2 m/s.
OUTCOME
Breaze was successfully able to track and follow a human
patient with smooth control implementation.
General overview of system.
Final Breaze product.
Closed-form triangulation.
SEAN M. REIDY
1024 Conception Drive • Lompoc, CA 93436 240-478-4734 • [email protected] • http://seanmreidy.com
ROBOCKEY 2013
MEAM 510 – Design of Mechatronic Systems
November – December, 2013
Collaborators: Klyde Breitton, Nick Labarbera
OVERVIEW
This is Robockey, the final project for MEAM 510. In
summary, Robockey is a 3v3 autonomous robot hockey
tournament. In 2013, there were close to 30 teams competing
in the tournament. Each robot used 4 LED “stars” above a
hockey rink to determine location and orientation data, and
then used scripted algorithms to find a puck, evade enemy
robots, and shoot the puck to their respective goal.
Our three robots had different functions – Robot 1 served only
to find the puck and score, Robot 2 rushed forward and
blocked other robots from Robot 1’s path, and Robot 3 was a
defender who stayed near our goal to attempt saves.
TECHNICAL APPROACHES
Each of our robots was powered by two 600mAh 9V batteries
- one for motor power, and one for logic. The robots are
controlled by an AVR microprocessor, and localization is
accomplished with the help of the Nintendo Wii sensor. All of
the manufacturing, electronics, and code were completely
original work by our team.
Seven IR phototransistors spaced around the bottom of the
bots served to detect a custom IR-LED puck. The robots are
designed to turn at different degrees/speeds depending on
which phototransistor has the highest value; they move slower
and turn tighter when the phototransistors near the back are at
a maximum, and move faster/turn very slightly when the ones
near the front are at a maximum. Proportional-Integral-
Derivative (PID) control is implemented to ensure smooth
movement.
All electronics were designed and manufactured by our team.
The exterior of the robots were composed primarily of acrylic
plastic and were designed using SolidWorks and
manufactured via laser cutting.
OUTCOME
Our team fared well in the round-robin portion of the
tournament – after 5 games, our team was undefeated.
Overall, we finished in the top third of the class, and felt
satisfied with our end product.
Robot 1 after initial assembly.
SolidWorks final rendering of Robot 3.
Robots 1 and 3 after the tournament.
SolidWorks Design of Robot 2.
SEAN M. REIDY
1024 Conception Drive • Lompoc, CA 93436 240-478-4734 • [email protected] • http://seanmreidy.com
BUNGEE CORD DESIGN
MEAM 348 – Mechanical Engineering Design Laboratory
January, 2014
Collaborators: Lars-Patrik Roeller, Robert Ritchie
OVERVIEW
In this lab, our team was tasked with designing a model for
bungee cords made of rubber bands, based off force-
displacement testing, energy methods, and statistical analysis.
Teams were given the mass of the “jumper” (in this case, a
0.5-1 kg mass), and height of the jump just 30 minutes before
a demonstration, and we needed to determine the cord
characteristics (how many rubber bands and series and how
many in parallel) and construct the cord in that time. Teams
needed to maximize free-fall length for the jumper, as well as
keep the force below 5 G’s. Our team constructed a script in
MATLAB, based on a force-displacement function that was
determined by stretch-testing. The output of our script
provided the number of rubber bands (in series and parallel)
which would provide the ideal bungee jumping conditions.
TECHNICAL APPROACHES
To determine the relationship between the stretching length of
a rubber band and the resultant force it exerts elastically, we
used a MTS force sensor on different combinations of
configurations – one in series, two in series, two in parallel,
etc. We then normalized this data to make displacement in
terms of percentage of the unstretched length of the bands, and
divided the total force by the number of parallel chains. The
force-displacement curves then collapsed into one curve; this
way, given a set of rubber bands with x bands in series and y
bands in parallel, we would be able to expand the force-
displacement curve to fit the configuration.
Our team’s MATLAB script to calculate the bungee cord
configuration took as input (a) the mass of the “jumper” and
(b) the height of the jump. Using our force-displacement
function, we determined an optimal strain for the rubber band
chain, and used energy methods to calculate the final
configuration.
OUTCOME
The final parameters on test day were a 0.555 kg jumper and a
42-foot drop. Our MATLAB script outputted a configuration
of 1-1/6 bands in parallel (in this case, doubling up every sixth
band) and 32 in series. Our team was successful in the
demonstration, achieving a force of 3.8 G’s and having the
jumper stop less than 3 feet above the ground.
Rubber band linking configuration.
Force vs. Displacement graph of
different rubber band configurations.
Normalized Force vs. Displacement.
Acceleration G-force data over time.
SEAN M. REIDY
1024 Conception Drive • Lompoc, CA 93436 240-478-4734 • [email protected] • http://seanmreidy.com
FORCED CONVECTION HEAT SINK DESIGN
MEAM 348 – Mechanical Engineering Design Laboratory
March, 2014
Collaborators: Kris Li, David Tompkins
OVERVIEW
In this lab, our team was to design a heat sink for a metal
plate. This metal plate would be heated by an electric current
and be placed in a wind tunnel to induce forced convection.
Our task was to dissipate heat on the plate for the largest area
possible. Evaluations were favorable for slow wind speeds,
high electrical power, and high heat dissipation. Temperature
readings were taken through a thermal imager.
This lab served to test our knowledge of heat transfer, to
complement a course my mechanical engineering class was
taking at the time, Heat and Mass Transfer.
TECHNICAL APPROACHES
Our team’s plan was to create as much surface area as possible
for our heat sink to maximize convection heat transfer with
the surrounding air. We chose to use thin sheets of aluminum
alloy with a high thermal conductivity to maximize area and
minimize mass. To keep under the mass limit of 150 g, we
would not have our heat sink span the entire area of the plate,
but put it near the back where the effects of the forced
convection from the wind tunnel would have the least effect.
Our design implemented a fan-like fin geometry. These fins
were spaced out in order to provide maximum “breathing
room” for the sink to increase fin efficiency.
To analyze our design, we ran a test in the wind tunnel. After
10 minutes (where the plate would reach steady state
temperature distribution), we used a thermal reader to take a
temperature reading of the plate. We used a MATLAB script
to read the image produced by the reader to determine the
success of heat dissipation.
OUTCOME
The final version of the heat sink yielded a 60% successful
area of heat dissipation, under conditions of 70% maximum
power and only 20% of wind power. This resulted in a
favorable evaluation by the teaching staff. Out of a field of 20
teams, our team placed third in our overall score.
SolidWorks rendering of heat sink.
Colorized thermal map of heated plate.
Temperature distribution as a function of
x-location on the plate.
SEAN M. REIDY
1024 Conception Drive • Lompoc, CA 93436 240-478-4734 • [email protected] • http://seanmreidy.com
SELF-BALANCING, TWO-WHEELED ROBOT
MEAM 510 – Design of Mechatronic Systems
November, 2013
Collaborators: Klyde Breitton, Nick Labarbera
OVERVIEW
The Acrobat was a self-balancing robot which used an inertial
accelerometer and gyroscope to stay on two wheels. This was
the penultimate project for our Design of Mechatronic
Systems class.
TECHNICAL APPROACHES
The robot kept balance by applying a motor torque from the
wheels to prevent the robot from tipping over.
Our acrobat robot featured a three tier structure, with motors
and circuitry on the bottom tier and a battery on the second
tier. The second tier had stabilizing wings that would help to
prevent the robot from falling completely over. The wings
also allowed the robot to sometimes bring itself back upright
after tipping too far over. Our robot had a wide base to allow
for stability and the ability to place most components as low
as possible to the wheel axis.
An accelerometer was mounted along the axis of the motors to
minimize noise caused by the radial acceleration of the robot.
Our code implemented a failure angle at which point the
motors would stop spinning. This allowed us to prevent the
robot from running off once it fell over. The failure angle
portion of the code can be seen in action at the ending of our
demonstration video where the robot lays still while resting on
one of the wings.
The code to determine the torque applied to the wheels
implemented Proportional-Integral-Derivative (PID) control.
The input for the controls was smoothed out using a digital
filter to eliminate noise.
OUTCOME
Our robot was able to start from an unbalanced position and
correct itself into an upright position. It was able to maintain
balance for well over 30 seconds. A video of the
demonstration can be found at the following link:
https://www.youtube.com/watch?v=7i9jIiKVaek
SolidWorks rendering of robot.
Finished Acrobat self-balancing.
SEAN M. REIDY
1024 Conception Drive • Lompoc, CA 93436 240-478-4734 • [email protected] • http://seanmreidy.com
MODELING OF MECHANICAL DEVICE
MEAM 101 – Introduction to Mechanical Design
October-November, 2011
Collaborators: Daniel Blank, Daleroy Sibadna
OVERVIEW
Our team was tasked with creating a full 3D model of an
electromechanical device. In particular, we were to model an
electric jigsaw in SolidWorks. We took apart the jigsaw,
modeled each part individually, and joined all parts in a
SolidWorks assembly. We then made a video of an exploded
view of the jigsaw, showcasing the detail we put into the
model and renderings.
TECHNICAL APPROACHES
Our team split the components up and modeled them
individually. We first discussed which measurements for our
parts would be in common and ensured that those would be
the same, to avoid issues with joining the assembly later on.
For modeling the different components, most of the work
involved tedious measuring and recording. Many hours were
put into creating the most accurate model possible.
After individual modeling, our team joined our parts together
in a SolidWorks assembly. The parts were successfully joined
and the full assembly was complete.
The final task was to create an animated exploded view of the
jigsaw. This served to display all of the small, intricate parts
that were modeled in the jigsaw that would otherwise not be
shown.
OUTCOME
The final video can be viewed at the following link:
https://www.youtube.com/watch?v=dQE_O1u12Gk
Rendering of central shell of jigsaw.
Rendering of central motor of jigsaw.
Designing the central motor in
SolidWorks.
Final enclosed jigsaw model.