Astro the Rover
Olympus Mons Rover Team
2014-2015
Purpose:
• Design a robotic vehicle capable of performing tasks for a
sample return mission within the parameters and
requirements of the University Rover Challenge.
University Rover Challenge:
• International robotics competition for college students.
• Held annually in the desert of southern Utah
• Challenges engineering students to design and build the next
generation of Mars rovers that will one day work alongside
astronauts exploring the Red Planet.
Mars Science Laboratory Curiosity Rover
Mars Exploration Rover Opportunity
Features:
6 Wheel Rocker Bogie Suspension
20 in Diameter Cleated Wheels
Independent Wheel Steering
Science Analysis Tools
5 DOF Arm
Stowage System
Features:
6 Wheel Rocker Bogie Suspension
1.5 m x 2.3 m x 1.6 m
Independent Wheel Steering
Safely Operational at 30° (max)
5 DOF Arm
Stowage System
Literature Survey
PHASE 1 PRELIMINARY DESIGN:
Olympus Mons Rover Team shall generate a list of key components and
modules for baseline approach.
PHASE 2 DETAILED DESIGNS:
Olympus Mons Rover Team shall finalize optical, mechanical, and
electrical design.
PHASE 3 MANUFACTURING:
Olympus Mons Rover Team shall create any necessary manufacturing
documentation and procedures.
PHASE 4 TESTING AND INTEGRATION:
Olympus Mons Rover team shall assist in creating a smooth, logical, and
efficient work flow.
Statement of Work
Project Schedule
Team Captain:
Christopher
Nguyen
Chassis:
Jerame Taylor
Weight
Distribution
Accommodating
Payload
Robotic Arm:
Lauren
DuCharme
Suspension:
Ken Greene
Wheels
Assembly:
Greg Maisch
Yolanda Mora
MelanieValenzuela
Quy Tran
Chris Thompson
Arm Design
Grippers
Rocker Bogey
System
Protecting Gear
Box and Motor
Rocker Arms
Connecting
Wheels to
Assembly
Telemetry/Visual
Systems:
Maria Gutierrez
Matt Wolfenden
Daniel Lu
Nathan Johnson
Carissa Pariseau1
Optics and
Moveable Visual
System
Camera
Orientations
GPS
Team Structure
Design Parameter
Requirement
Entire Vehicle Weight
< 50 kg
Vehicle Volume
< 1 m3
Vehicle Width
< 32 in
Functional Temperature Range
Up to 110°F
Minimum Lift Capacity
5 kg
Movement Control
Wireless/Remote Control
Minimum Reach Capability
5 cm below ground
Science Tools
pH and humidity meter
Video Feed
Wireless
Frequency Band
900MHz-2.4GHz
A-Specs
Features:
6 Individually controlled wheels
Rocker bogie suspension
7.5 in diameter RC wheels
3 DOF Arm
Closed loop feedback system
ION Rover 2014
ION Rover 2015 Concepts
• 2014: Used square wood
base with aluminum
channel siding
• Electronics not protected
from environment
• Limited space
• Structurally unstable and
weak
Chassis Design Concepts
Function
Provide Support to
Vehicle
Maintain Shape and
Strength
Maneuverable
Possible Solution
C-Channel
Bar-Stock
Flat, Solid
Tubing
Aluminum
Steel
Plastic PVC
Carbon Fiber
Circular
Octagon
Square
Bi-Level
--
--
Rectangular
Box
Provide Space for Arm
and Electrical
Flat
Components
Chassis Morph Chart
• 2015: Aluminum frame with
aluminum base plate
• Bi-level design
• More easily
accommodates
electronic components
• Second level could act
as cover to protect
components from dust
or rocks
• Change in shape to prevent
wheel or suspension
interference
Final Design Concept
• 2014: Rocker bogie
suspension (2 rocker
arms/2 bogies)
• Middle wheel slippage
• Low vertical travel
abilities
• Bulky and underoptimized
Suspension Design Concepts
Function
Possible Solution
Support Chassis Weight
8 wheels
6 wheels
4 wheels
Smooth Pivot Points
Bearings
Bushings
None
Rocker Length within A-Specs
14”
15”
12”
Bogie Length within A-Specs
14”
13”
12”
Attachable to Assembly
4 Bolt Pattern
Single Post Free
Single Post Fixed
Support Load
0.25” Tall
0.375 Tall
0.50 Tall
0.125” Thick
0.25” Thick
0.375” Thick
Maintain Shape and Minimize
Deflection
Suspension Morph Chart
• 2014: Differential link
• Heim joint had too
much play
• Under-designed
• Difficulties with
alignment and
concentricity on
rotational point
Suspension Design Concepts
Function
Possible Solution
Differential Type
Differential Link
Shaft (3 Bevel Gears)
Shaft (4 Bevel Gears)
Shaft Diameter
1”
0.75”
0.5”
Bevel Gear Ratio
1:1
2:1
1.5:1
Full Aluminum
Full Carbon Fiber
Set Screws
Spring pins
Shaft Material
Mating Mechanism
Carbon Fiber with
Aluminum Ends
Keyways
Suspension Morph Chart
• 2015: Rocker Arm
and Bogie
• Optimized for weight
and strength
• Even weight
distribution across
wheels
• Clearance for 90°
departure and
approach
Final Design Concepts
• 2015: Shaft with
bevel gears
• 1:1 rotational ratio
in rocker arm
• Improved
concentricity
difficulties
• More easily
manufactured
Final Design Concepts
• 2014: Modified 1/5 scale
RC wheels
• Non-pneumatic tires
• Required custom
components
• Lacked motor adapters
• Non consistent
compliance with
substrate
• Bulky assembly
• Sufficient traction
Wheels Design Concepts
Function
Possible Solution
Maintain Traction
Rubber Cleats
Pneumatic
Foam and Tread
Meet Size Requirements
8 in
10 in
9.5 in
Motor Placement Protects
Gearbox Away from
Gearbox Above
Power System
Wheel
Wheel
Should be Light Weight
Rubber
Aluminum
Single Piece
Pocketed Single
Aluminum
Piece Aluminum
Configuration
Configuration
Must be Easy to
Manufacture
Wheels Morph Chart
--
Stainless Steel
Separately Machined
Aluminum Plates
• 2015: Custom
Wheel
• 10 in diameter
• Not pneumatic
• More compact
• Light weight
• Elevated motor and
gearbox
• Helps prevent
damage from
rocks and dust
• Lower rotational
inertia
Final Design Concept
• 2014: 3 DOF Planar
Arm
• Simple control system
forward kinematics
• Limited range of
motion
• Insufficient strength to
complete URC
requirements
• Incapable of stowing
Robotic Arm Design Concepts
Function
Possible Solution
Control and Power Systems
Linear actuator
Servo
Stepper Motor
Closed loop
linkage
Must Attach to Gripper
Interface Bracket
Directly Mounted
Removable
Linkage
Ball screw joint
Should Be Stowable
Pre-Programmed
Upward
Configuration
Pre-Programmed
Downward
Configuration
Manual Upward
Configuration
Manual
Downward
Configuration
Length Must Have Sample
Collection Reachability
25”
36”
20”
18”
Workspace Must Allow for
Task Completion
Below
Above
Adjacent to the
chassis
All the above
End Effector Must Have
Position Capabilities
Linear actuator
Servo
Stepper Motor
Ball screw
Must Be Mounted to Chassis
Top
Bottom
Center
Rear
Arm Morph Chart
• 2014: 2 finger parallel
gripper
• Insufficient range of
motion
• Lack of friction grip
abilities
• Insufficient strength to
complete URC task
requirements
• Single end effector not
optimized for each task
End Effector Design Concepts
Function
Multi-Task
Possible Solution
Removable Gripper
Fingers
Removable Gripper
Removable Final Linkage
w/ Gripper
Sample Collection
Capability
Scooping Jaws
Sample Coring Drill
Sample Coring Probe
Sample Containment
Capability
Glass Beaker on Top of
Chassis
Canvas w/ Framing on
Side of Chassis
Bag Attached to Gripper
pH Analysis Capability
pH Cards in Sample
Receptacle
pH Probe in Sample
Receptacle
Electronic pH Sensor w/
Arduino
Humidity Analysis
Capability
pH Cards in Sample
Receptacle
Humidity Probe in Sample
Receptacle
Electronic Humidity
Sensor w/ Arduino
Astronaut Assistance
Capability
3 Finger Gripper with
Independent Control
3 Finger Gripper with
Overall Control
2 Finger Gripper
Servicing Task
Capability
Re-use Astronaut
Assistance Gripper
Conveyer Belt Finger
Gripper
3 Finger Angled Gripper
Functionality
End Effector Morph Chart
• 2015: 3 DOF Planar
Arm
• Larger workspace to
accommodate
multiple tasks
• Utilizes 4 bar
linkage with linear
actuator
• Configuration can be
stowed to prevent
damage during terrain
traversing
Final Design Concept
• 2015: Complete redesign
that features custom
grippers for each task
• Longworth chuck
• Equipment servicing
task
• Knurled fingers for
added grip
• Single finger actuation
gripper
• Astronaut assistance
• Encompassing grip for
handles and object
retrieval
• Sample collection scoop
• Sample return task
• Bulk sampling and
collection
Final Design Concepts
• 2014: Telemetry
system
• Individually
controlled wheel
• Single Camera
Visual – via FPV
• Unstable pan/tilt
servos
• Lacked Visual
Clarity
Telemetry Design Concepts
• 2015: Arduino Mega: 54 I/O Pins, Input
Voltage: 7-12V
• Arduino Uno: 16 I/O Pins, Input Voltage:
7-12 V
• HS-5685MH Servos (end effectors min.
3):
• Operating Voltage: 4.8-7.4V
• Radio Frequency:
• Video feed: 5.8 GHz
• Control: 2.4 GHz
• Antenna: (Cloverleaf & Air Max Bullet)
• Power Rating: up to 24V
Final Design Concepts
Features:
6 Wheel Rocker Bogie Suspension
10 in Diameter Cleated Wheels
Independent Wheel Steering
3 DOF Arm with 3 Custom Grippers
ION Rover 2014-2015
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Jesse Grimes-York
Brett Kennedy
Jet Propulsion Laboratory
Dr. Nina Robson
Dr. JiDong Huang
Ye Daniel Lu – CSUF Electrical Engineering Student
CSUF Geology Department
CSUF Electrical Engineering Department
CSUF ION Website Design Team
Acknowledgements