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Team HazardHawk Team HazardHawk 2008 April 24, 2008
Team HazardHawk
Team HazardHawk 2008
April 24, 2008
Presentation Outline Objective Project Overview Design Requirements Concept Selection Key Technical Challenges Performance Requirements Prototype: Materials / Fabrication / Assembly Electronics / Software Overview Design Status Feasibility Assessment Prototype Performance Questions
Objective
Team HazardHawk 2008
Task: Develop an autonomously-controlled, electric-powered vehicle whose purpose is to demonstrate the integration of technologies needed to locate a “hazardous material” in an open field.
Project Overview
Key FeaturesAutonomous GPS NavigationHazardous Materials Sensor to locate and sample hazards
Main ConsiderationsCan operate in a large open fieldCan locate a hazard and return to start point quicklyNavigation of a variety of terrains with surface obstacles
Team HazardHawk 2008
Design Requirements
Autonomous, electric-powered GPS enabled, accurate to within 1 meter (3.28 ft) Maximum weight: 35 kg (77.1 lb) Maximum size: 1 meter (3.28 ft) in any
dimension Top Speed: 8 m/s (17.89 mph) Hazard detection in under 1 minute when within
100 meters of hazard
Team HazardHawk 2008
Concept SelectionIndividual Concepts
Individual Concepts were developedKey Features of interest merged into group concept
Concept SelectionGroup Concept
Target Market: Public Service SectorFire Department, Police Department, Hazmat, and other
public agencies
Prototype DesignFeatures
Key Features Included:Autonomous GPS
NavigationInfrared ‘Hazard’ SensorsRetractable Oscillating
ArmTank Drive
Key Technical Challenges
Establishing navigational precision and awareness of location using imprecise GPS data
The Oscillating Robotic Arm:Material and geometry selection for a strong,
lightweight armKinematics
Hazard Sensing MethodologyDetermining optimum search height and orientationDeveloping logic for search algorithm
Key Technical ChallengesDesign of Arm Assembly
Material Selection, Member Length, Oscillation Speed Materials Considered: Carbon Fiber, PVC, Plywood, and HDPE Longer-the-Better Factor of Safety of 4 Optimal:
○ 30 in members○ ω = 2.3 rad/sec Normalzed Yield Stress vs. Member 2 Length - w = 5 rad/sec
0.0
2.0
4.0
6.0
8.0
10.0
12.0
18 20 22 24 26 28 30 32 34 36 38 40 42
Member 2 Length [in]
Norm
aliz
ed Y
ield
Stre
ss (s
_yie
ld /
s _m
ax)
Carbon Fiber
Plywood
HDPE
PVC
Key Technical ChallengesSensor Sensitivity
Goal: to search at a height where the conical infrared signal emitted by the hazard has a large diameter
Height constrained by the vehicle size performance requirement
Result: Search at the maximum height and a downward orientation
Detection radius is 8.3 in at search height h= 42 in.
Key Technical ChallengesGPS Navigation
Sought to determine optimal search direction
Due north most accurate approach direction
Average deviation of 2.2 ft
Due North Residuals: 1 ft/sec
Prototype Requirements Weight < 70 lbs Dimensions < 3 feet in any direction Complete Task < 8 minutes Responsive user interface Maneuvers autonomously via GPS Seeks and reaches hazard Identifies target as hazard Returns to start position Deactivates upon completion
Team HazardHawk 2008
Prototype DesignFabrication
AssemblyCNC manufacturing for precise
sizing of body panels, arm base, and mounts
Custom Cut Shafts, ChainWheel AssemblyMount AssemblyArm Assembly
Prototype DesignFabrication
Assembly:Body Panels attached with
corner braces Motor Mounts and Bearing
Mounts attached to base with ¼” bolts to allow for adjustability
Arm fabricated with PVC, assembled with ¼ in bolts.
ElectronicsOverview
Prototype Software Flowchart Acquire Hazard
Coordinates
Continue Straight
Carry to Start
Acquire Start Coordinates
Within 3 ft of X-Cor.
East or West of target
Acquire New Coordinates
dx increases?
Add 1 to counter
Counter > 2?
Turn Around
North or South
Continue Straight
Acquire New Coordinates
dy increases?
Add 1 to counter
Counter > 2?
Turn Around
No No
Yes YesYes
YesYes
No NoNo
Within 3 ft of Y-Cor.
No
Yes
Rotate arm. When hazard is found return to start coordinates
Design Status
Video
Team HazardHawk 2008
Prototype Performance Weight < 70 lbs 60.7 Lbs 10/10 Dimensions < 3 feet in any direction 15 x 16 x 36 in 15/15 Complete Task < 8 minutes N/A 0/15 Responsive user interface Yes 10/10 Maneuvers autonomously via GPS w/out Arm 7/10 Seeks and reaches hazard w/out Arm 7/10 Identifies Hazard Yes 10/10 Returns to start position w/out Arm 7/10 Deactivates upon completion Yes 10/10
Total: 76/100
Prototype
Team HazardHawk 2008
Feasibility Assessment
GPS Navigation, Arm Mechanism, IR Hazard Detection are all feasible.
Showstopper: Drive Train Sensing technology needs to be developed Further development is advised
Lessons Learned
Importance of hardware/software integration
Parallel Development Importance of a thorough CAD model Project planning and delegation of
responsibilities Problems with outsourcing parts
QUESTIONS?
Team HazardHawk 2008
