AGVS Guidance Systems and Routing

AGVS

Guidance Systems And Routing

Kevin Ferguson Goodyear Tire & Rubber Co.

Slide 1

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2000 Kevin W. Ferguson

AGVS Overview

• Components – Controller – Sensors – RF Modem • Vehicles – Fork Truck – Tow Truck – Conveyor Deck – Scissor Lift • Guidance Systems and Routing

AGVS Guidance Systems and Routing Slide 2

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2000 Kevin W. Ferguson

Problem Area

• How Does a Company Choose a

Guidance System?

• What Things Need to Be Considered

When Choosing a Route?

AGVS Guidance Systems and Routing Slide 3

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2000 Kevin W. Ferguson

Guidance Systems (1)

• Wire Guidance – Wire Placed in Floor – Vehicle Follows Wire • Coils Straddle Wire in Floor • Voltage Difference is 0 When Centered • If Off Center, Coils Create Steering Signal – Disadvantages • Vehicle May Not Know Location • Not Flexible – Advantages • Reliable • Good for Dirty Environment

AGVS Guidance Systems and Routing Slide 4

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2000 Kevin W. Ferguson

Guidance Systems (2)

• Optical Guidance Systems – Use Paint or Reflective Items on Floor – Light on Bottom of Vehicle Reflects off

The Paint/Items

– Sensors Detect Light and Guide Vehicle – Disadvantages • Paint/Items Wear • Must Be Clear of Obstructions – Advantages • Flexible • Easy to Repair

AGVS Guidance Systems and Routing Slide 5

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2000 Kevin W. Ferguson

Guidance Systems (3)

• Laser Guidance – Laser Scanner Looks for Reflective

Targets

– Scanner Measures X and Y Coordinates

from Targets

– Target Locations are Preprogrammed – Needs Three to Five Targets in “Sight” – Disadvantages • Requires Additional Setup Time • 15-30% Increase in cost – Advantages • Flexibility • Used in Rough Terrain

AGVS Guidance Systems and Routing Slide 6

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2000 Kevin W. Ferguson

Guidance Systems (4)

• Inertial Guidance System – Gyroscope Detects Accelerations – Information from Gyroscope is sent to

Controller to Direct AGV

– Disadvantages • Parts Wear • To Be Effective, System Needs Additional

Guidance Devices

– Advantages • Flexibility • Reliable

AGVS Guidance Systems and Routing Slide 7

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2000 Kevin W. Ferguson

Guidance Systems (5)

• Dead-Reckoning – Rotation and Steer Angle Are Measured – Wheel Slip Gives False Readings • The Future – More Laser Guided Systems – Use of GPS

AGVS Guidance Systems and Routing Slide 8

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2000 Kevin W. Ferguson

Routing Considerations

• Number of Vehicles • Floor Space • Static Guide Path – Unidirectional – Bi-directional • Dynamic Path • Source/Delivery Points • Routing Efficiencies

AGVS Guidance Systems and Routing Slide 9

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2000 Kevin W. Ferguson

Conclusions/Implications (1)

AGVS Guidance Systems and Routing

• Systems Have Merit • Must Carefully Consider Desires for

System Prior to Selecting Route and Guidance System

• Wire Guided Systems are Most Reliable • Laser Guided Systems Maximize

Flexibility Slide 10

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2000 Kevin W. Ferguson

Conclusions/Implications (2)

AGVS Guidance Systems and Routing

• AGVS Use Computers Instead of People • AGVS Offer Coverage Around the Clock

at No Additional Cost

• Another Application of Computer

Integrated Manufacturing Slide 11

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2000 Kevin W. Ferguson