AGVS

1

• AGVS
• Guidance Systems
• And Routing
• Kevin Ferguson
• Goodyear Tire Rubber Co.

2
AGVS Overview

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

3
Problem Area

• How Does a Company Choose a Guidance System?
• What Things Need to Be Considered When Choosing a
  Route?

4
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

5
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

6
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

7
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

8
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

9
Routing Considerations

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

10
Conclusions/Implications (1)

• 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

11
Conclusions/Implications (2)

• AGVS Use Computers Instead of People
• AGVS Offer Coverage Around the Clock at No
  Additional Cost
• Another Application of Computer Integrated
  Manufacturing