M E T ROVER MSCD Engineering Technology Critical Design Review Metropolitan State College of Denver April 2004

Mission Description Deploy rover from the payload carrier upon landing. Image flight and landing site autonomously. Accomplish mission under strict mass limitations.

Mission Goals Design and build an autonomous rover and 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

NASA Benefits Prototype development which may be used during future missions to Mars or the moon. Test existing paradigms of rover design. Explore new methods of rover design, construction, and deployment.

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 system allowing it to maneuver on the ground at the landing site.

Mass Budget Carrier400g Camera (w/out battery)166g Drive motor/gearbox assembly200g Chassis & Electronics400g Wheels 400g WindSat addition234g Total 1800g

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.

Rover Design

Wheel Design

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 two possible carrier landing orientations. Incorporate obstacle avoidance system.

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

Drive System Interfaces Orientation Sensor Obstacle Sensor Controller Drive Arms Motors

Drive System Prototyping Aluminum wheels: Machined from solid 4.25 inch diameter aluminum bar stock. Goal weight (mass) of 100 grams per wheel. Drive arms machined from ¼” x ¾” stock.

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.

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

Carrier Design

Imaging System Digital video system will be employed to document entire flight plus image landing site. Mounted to the Rover so multiple views of the landing site will be recorded upon deployment.

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.

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.

Electrical Systems Embedded Computer Sensors Subsystem Actuators Subsystem USB Subsystem GPS Subsystem

Subsystem - Stamp (Sensors) Purpose: Read data from sensors, communicate with embedded computer Interface: SPI (Serial Peripheral Interface)

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

Subsystem - Stamp (Actuators) Purpose: Control actuators, communicate with embedded computer Interface: SPI (Serial Peripheral Interface)

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

Subsystem – USB Purpose: Provide communication between embedded computer and USB Devices Interface: System Bus

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

Subsystem – GPS Purpose: receive GPS signals and communicate coordinates to embedded computer Interface: RS232 Serial

Subsystem – GPS Gamin GPS OEM RS232 Serial Interface Embedded Computer Antenna

Power Budget (incomplete)

Budget (Electronics/Software)

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

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.

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

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

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