M E T ROVER MSCD Engineering Technology

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M E T ROVER MSCD Engineering Technology

• Critical Design Review
• Metropolitan State College of Denver
• April 2004

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Mission Description

• Deploy rover from the payloadcarrier upon
  landing.
• Image flight and landing site autonomously.
• Accomplish mission under strictmass limitations.

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Mission Goals

• Design and build an autonomous roverand its
  carrier under strict mass limitation of 1.8 kg.
• Incorporate imaging system on the rover to video
  entire fight and the landing site.
• Carrier Rover must survive
• high altitude
• extreme cold temperatures
• impact forces during landing
• Include additional Windsat mission into Rover
  package

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NASA Benefits

• Prototype development which maybe used during
  future missions toMars or the moon.
• Test existing paradigms of rover design.
• Explore new methods of rover design,
  construction, and deployment.

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Project Requirements

• Carrier and Rover combined must meet 1.8 kg mass
  limitation.
• Rover must image the landing site.
• Rover must deploy at the landing site.
• Rover must have a drive systemallowing it to
  maneuver on the groundat the landing site.

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Mass Budget

• Carrier 400g
• Camera (w/out battery) 166g
• Drive motor/gearbox assembly 200g
• Chassis Electronics 400g
• Wheels 400g
• WindSat addition 234g
• Total 1800g

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Rover Design

• Must operate in either orientation.
• Drive arms move to raise chassis height.
• Each wheel has independent motor.
• Chassis made of carbon fiber composite.
• Electronics will be insulated inside chassis.

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Rover Design
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Rover Design
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Wheel Design
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Rover Drive System

• Drive the Rover out of the carrier and around the
  landing site.
• One electric motor per wheel to get four wheel
  drive and steering.
• Operate the rover in either of twopossible
  carrier landing orientations.
• Incorporate obstacle avoidance system.

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Drive Components

• Orientation sensor.
• Drive motors inside each wheel.
• Movable side arms to raise chassis height.
• Obstacle avoidance system.
• Drive wheels.

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Drive System Interfaces
Orientation Sensor
Obstacle Sensor
Controller
Drive Arms
Motors
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Drive System Prototyping

• Aluminum wheels
• Machined from solid 4.25 inch diameteraluminum
  bar stock.
• Goal weight (mass) of 100 grams per wheel.
• Drive arms machined from ¼ x ¾ stock.

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Carrier System

• Securely carry the Rover payload to high altitude
  and back.
• Constructed foam and carbon fiber composite.
• Open to allow the deployment of the Rover upon
  landing in correct orientation.

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Carrier Components

• Air piston system to open carrier
• Foam-core with carbon fiber Carrier.
• Rover door latching mechanism.
• Rover opening mechanism.

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Carrier Design
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Imaging System

• Digital video system will be employed to document
  entire flight plus image landing site.
• Mounted to the Rover so multipleviews of the
  landing site will be recorded upon deployment.

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Imaging Components

• Panasonic SD mini digital video camera.
• MPEG4 video compression.
• Over 2 hr. 20 Min. of recording time.
• 320x240 dot/ 420 Kbps.
• 512 MB memory card.
• Solar power unit to power video camera.

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Electrical Requirements

• Control and operate the Imaging Drive Systems.
• Open the Rover carrier upon landing.
• Orientate the Rover and chassis.
• Direct rover around obstacles.
• Process and store in flight data.

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Electrical Systems
Embedded Computer
Actuators Subsystem
Sensors Subsystem
USB Subsystem
GPS Subsystem
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Subsystem - Stamp (Sensors)

• Purpose Read data from sensors, communicate with
  embedded computer
• Interface SPI (Serial Peripheral Interface)

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Subsystem - Stamp (Sensors)
Embedded Computer
BASIC STAMP II Controllers
Altimeters
Temp Sensors
SPI Interface
Tilt Sensors
Digital Compass
Wheel Encoders
Arm Angle Encoders
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Subsystem - Stamp (Actuators)

• Purpose Control actuators, communicate with
  embedded computer
• Interface SPI (Serial Peripheral Interface)

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Subsystem - Stamp (Actuators)
Embedded Computer
BASIC STAMP II Controllers
Parallax Servo Controller
Servos
SPI Interface
Pololu Motor Controllers
Motors
Relays
LCD
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Subsystem USB

• Purpose Provide communication between embedded
  computer and USB Devices
• Interface System Bus

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Subsystem USB
Embedded Computer
Hub
TD OT243 USB Host Controller
Camera 1
Camera 2
System Bus Interface
Hub
Camera 3
Flash Memory
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Subsystem GPS

• Purpose receive GPS signals and communicate
  coordinates to embedded computer
• Interface RS232 Serial

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Subsystem GPS
Embedded Computer
Gamin GPS OEM
RS232 Serial Interface
Antenna
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Power Budget (incomplete)
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Budget (Electronics/Software)
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Prototyping (Electronics/Software)

• Set up development computer with compiler, dev
  tools, NFS. Ran simple program on embedded
  computer to flash LED's
• Tested various USB cams and software
• Experiences/Hardware from last year

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Electronics Components

• Altitude sensor.
• Rover orientation sensor.
• Obstacle avoidance sensor.
• Micro-controller.
• Wiring to/from sensors, camera and drive motors.
• Carrier door latch servo.
• Onboard programming.

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Project Organization
Professor Keith Norwood
Don Grissom Team Lead
Power Oscar Matt Luke Nathan Chris Amparo
Imaging Brian Don Chris
Carrier Oscar Leah Walter John
Electronics Luke Nathan Amparo
Chassis John Walter Matt Leah Brian Don
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Budget

• Expenses to date
• Beginning total 4000
• Carbon fiber materials 150
• Camera 800
• Motors/gearbox assy. 40
• Wheel material 100
• Machining tools 50
• Carrier material 30
• Misc. Material and Electronics 1800
• subtotal 2970
• Remaining Balance 1030

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Schedule

• Construction Completed June 15
• Operational testing Completed July 20
• Final Construction Completed July 30
• Mission Readiness Review July 30
• Launch Readiness Review Aug 6
• Launch Aug 7