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]

No

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ized

Yie

ld S

tres

s (s

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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