A sample of engineering projects I have worked on. Includes my Major Qualifying Project, two autonomous robots, and two remote controlled robots.

1. Engineering Portfolio
A sample of projects by Corbin Grubb
Stomatobot

2. Contents
WPI Aerospace Engineering
Major Qualifying Project
• Lunar Micro Rover
Autonomous Robots
• Swanbot
• Argus
Remote Controlled Creations
• Stomatobot
• SkiBot

3. LUNAR MICRO ROVER
WPI Aerospace Engineering Major Qualifying Project
Design and analysis led by Corbin Grubb

4. PROJECT GOAL AND CONSTRAINTS
▸ Design a rover to explore the
Lunar South Pole
▸ Build and test a prototype rover
▸ Rover must weigh less than 5 Kg
▸ Rover must carry a 2 Kg scienti
fi
c
payload
▸ Rover must survive a 4-inch drop
in earth gravity
Rover during early testing

5. DESIGN PROCESS
Several design options were considered to meet
the project requirements, and two best design
options were selected. Simple CAD models were
created in SolidWorks to compare the weight,
payload space, complexity, and obstacle clearing
ability of each option.
The four wheel rocker design was selected, and
fi
nal CAD designs were developed in SolidWorks,
using of-the-shelf components whenever possible.
ANSYS was then used to verify the strength of the
design and to optimize the design wherever
possible.
Preliminary 2-Wheel Design
Preliminary 4-Wheel Rocker Design

6. DESIGN FEATURES
▸ Chassis (1) holds the scienti
fi
c payload
and control electronics
▸ Rockers (2) rotate freely relative to the
chassis to overcome obstacles
▸ Motor gearboxes (3) provide power to
each wheel individually
▸ Large wheels (4) provide traction in
lunar regolith
▸ Differential Linkage (5) keeps chassis
at the average angle of the two rockers
Final SolidWorks Model
(1)
(2)
(3)
(4)
(5)

7. STRUCTURAL ANALYSIS
To ensure the design could survive a
4 inch drop, a simpli
fi
ed CAD model
was created and ANSYS Explicit
Dynamics was used to simulate the
impact.
The results from the Explicit
Dynamics simulation were then used
to develop ANSYS Static Structural
simulations to test the
fi
nal CAD
model
ANSYS Static Structural simulation on
fi
nal design
ANSYS Explicit Dynamics drop test with simpli
fi
ed CAD model

8. WHEEL DESIGN AND OPTIMIZATION
The wheels of the rover were heavy and mission critical
components, so extensive real-world and ANSYS tests were run
to optimize the design.
Real-world testing was performed to determine the shape of
the traction
fi
ns.
ANSYS simulations were run to determine the radial and
tangential strength of the wheels using the data from the
Explicit Dynamics drop test.
Real-world traction testing
Radial strength ANSYS test Tangential strength ANSYS test
With each ANSYS simulation, the
design of the wheel was adjusted
to reduce weight.
The
fi
nal design had a factor of
safety of
fi
ve throughout most of
the wheel.

9. ROVER TESTING
The rover was tested climbing over a
range of obstacles and terrains. The rover
successfully overcame objects up to 150
mm high, equal to the diameter of the
wheels.
The rocker suspension system proved
effective at reducing the motion of the
chassis as the rover climbed uneven
terrain.
The wheel design demonstrated adequate
grip in the simulated lunar regolith.
Rover overcoming large obstacle

10. CREDITS
MECHANICAL/ANALYSIS TEAM:
Corbin Grubb
Will Fisher
Caleb Powell
Marcela Mayor
ELECTRICAL/CONTROLS TEAM:
Travis McGregor
Zachary Angell
Lily Kinne
David Acuna
MISSION PLANNING:
Watts Herideen-Woodruff
ADVISOR:
Professor Nikhil Karanjgaokar
SPECIAL THANKS:
WPI Academic Computing Lab
WPI Practice Point Lab
Daniel Ali Tribaldos

11. Swanbot
Autonomous Panel Moving Robot
Designed, simulated, and printed by Corbin Grubb
Created for RBE 2001

12. Body Design Goals
• Bot must be able to reach 4” by 4” by
1/4” panel at three unique heights and
angles
• Must only have one degree of freedom
in upper linking
• Must connect to Pololu Romi kit
• Must have proper gear transmission,
where needed input torque is less than
10% of motor stall torque
• Minimal moving parts
•

13. Gripper Design Goals
• Must be able to hold and release a 4” by
4” by 1/4” stainless steel plate
• Must need no input torque to maintain
grip
• Must require no more than 0.25 kg/cm
of torque at any point
• Must only have one degree of freedom
• Minimal moving parts
•

14. Body Features
• Gripper ( 1 ) grabs and releases the
target plate
• Gear train ( 2 ) reduces input
torque needed from blue motor
( 3 )
• Four-bar mechanism maneuvers
gripper to the three required
angles
• Curved upper link and angled
blue motor unintentionally gave
robot a swanlike appearance
( 3 )
( 1 )
( 2 )
( 4 )

15. Gripper Features
• Lower plate ( 1 ) supports weight
of the target plate
• Compliant gripper “claw” ( 2 )
prevents plate tipping or sliding
off lower plate
• 9 Gram servo motor ( 3 ) actuates
gripper
• Two bearings in the rear ( 4 )
attach to rest of Swanbot
( 3 )
( 1 )
( 2 )
( 4 )

16. Four-bar design
To determine the proper four-bar
mechanism, a sketch was made in
Solidworks featuring the gripper in
the three required positions.
The mounting/pivoting points of the
gripper were then used to
f
ind the
necessary lengths for the “rocker”
links and the location of the
“ground” link.

17. Simulation of flexible gripper
Color scale represents displacement
Maximum force of 1 newton
Compliant mechanism

18. Implementation
• Compliant gripper part 3D
printed in TPU plastic
• Gripper body and servo lever
printed in ABS plastic
• 3 mm steel rods used as guide
rails to prevent twisting
• Base plate, body walls, gears,
links, and spacers were 3d
printed in ABS and PLA
• M3 bolts were used as pins
and axels
• Ball bearings were press-
f
itted
into the gears

19. Swanbot performing its duty
Swanbot in action

20. Argus
Autonomous Map Making Robot
Sensor integration, Coding, and Testing by Corbin Grubb and Team 16
Created for RBE 2002

21. Mission Goals
• Bot must be able to circumnavigate area
autonomously
• Must take measurements of internal
object in two environments
• Must convert distance measurements to
an accurate maps of the objects
• Must connect to Pololu Romi kit

22. Argus Features
• Pololu Romi Chasis ( 1 ) for
mobility, with a A
-
Star 32U4
board running C++ code
• IR range sensor ( 2 ) for following
the outer wall of the arena
• Ultrasonic Sensor ( 3 ) for
measuring distance to object
• Esp32 Board ( 4 ) for uploading
map to a server via WiFi
• Argus’ name comes from
additional cosmetic ultrasonic
sensors ( 5 ), as Argus is a man
with 100 eyes from greek
mytholo
g
y
( 3 )
( 1 )
( 2 )
( 4 )
( 5 )

23. Mapping Process
• Robot uses a State Machine to
traverse the arena and collect data
• Robot begins at a known location in
the “idle” state, and begins when a
button on the board is pressed
• Robot begins crossing the arena
using the IR sensor to follow the wall
• At set distance intervals, the robot
switches to a measurement state and
collects 100 measurements of the
object to be averaged and used to
f
ill
one cell in a matrix
• The robot repeats this process until it
reaches the far wall, then it moves to
the other side of the arena
• The measuring process is repeated in
the opposite direction

24. Results
• Argus successfully mapped the
objects in both arenas
• Robot retuned within 10 cm of
original spot
• Both matrices were uploaded to a
web server live
Example of a matrix. 1s represent
blocks mapped during the
f
irst pass,
2s represent blocks mapped during
the second pass, and 3s represent
blocks mapped during both passes

25. Stomatobot V0
Ant-Weight Combat Robot
Designed, built, and driven by Corbin Grubb,
As a part of the WPI Robotics Club

26. Inspired by Mantis Shrimp
(Stomatopods), Stomatobot V0
served as a functional prototype for
future ant-weight combat robots.
Stomatobot V0 featured six klann
mechanism legs, and a hard shell
supported by stiff plastic springs.
An asymmetrical vertical spinner
was used for the active weapon.
The robot was designed in Fusion
360.

27. For using legs instead of wheels,
the bot was granted a weight limit
of two pounds, twice the limit for
wheeled bots.
All parts for Stomatobot V0 were
3D printed, with screws, bearings,
and electronics as exceptions.
The bot used a 3-cell LiPo battery,
two brushed drive motors, and a
brushless weapon motor, with a
receiver and two ESCs to control
the bot.

28. As an experimental prototype,
Stomatobot V0 only won one of
its
fi
ve
fi
ghts, but sustained little
damage.
The
fi
ghts proved the resilience
of the shell, but the bot lacked
maneuverability.
Several design changes are
being implemented in
Stomatobot V1, as well as a
“Club” weapon.
Stomatobot V0 with minor damage to the shell
and weapon, and a broken weapon mount

29. SkiBot
Radio Controlled Skiing Robot
Designed, built, programmed, and tested by
Corbin Grubb
Cosmetic cover made by Nate Stote and Corbin Grubb

30. • Mimic the motion of human skiing
• Have all electronics contained
within rectangular body
• Be capable of propulsion and
steering
• Be remote controlled
• Look like a certain cartoon robot
Design Goals

31. • An Arduino Uno ( 1 ) receives
signals from a radio receiver
board
• Arduino drives a brushed motor
( 2 ) through a PWM driver board
• Motor drives a ~15:1 gearbox
that in turn drives the Klann
mechanism arms ( 3 )
• Servo motor changes the relative
height of the legs to tilt robot and
steer ( 4 )
SkiBot Features
( 1 )
( 2 )
( 4 )
( 3 )

32. Finished Robot