Agile Robotics
Platform Integration
Mitch Leammukda, Troy Jones, Lenny Paritsky, Rob Truax,
Mofe Uku, Paul Pepin, Steve Proulx, Mike Kerekes
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
Forklift Platform

Toyota 8FGU15
◦ 3k lbs. capacity
◦ Liquid propane gas fuel
◦ Electrically-actuated
mast hydraulics
◦ CANbus network
◦ Pneumatic tires
◦ Internal sensors and
safety override system
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
Toyota 8-Series Features

System of Active Stability (SAS)
◦ Internal sensors detect instability and forklift’s
controllers activate appropriate functions
 Active Control Rear Stabilizer System
 Speed sensor
 Yaw rate sensor
 Swing Lock Cylinder
 Active Mast Function Controller System
 Pressure sensor
 Height (stage) sensor
 Tilt angle sensor
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
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Forklift Pics
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
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Modifications

Several components on forklift need to be
modified to be a computer-controlled driveby-wire system
◦ Mechanical/Hydraulic (major mods)
 Steering
 Hydraulic brake
 Parking brake – engagement & release
◦ Electrical (minor mods)
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

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Mitch Leammukda
Mast degrees of freedom (DOFs)
Accelerator
Transmission
Lights, alarms, etc.
Agile Robotics Site Visit
8/8/2008
5
Steering
shaft
Steering


Hydrostatic steering
pump transfers
hydraulic fluid to
move steer wheels
Hydrostatic
pump
Implement gearbox,
pulley, motor/clutch
driven by Copley
Accelnet motor
controller
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
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Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
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Hydraulic Brake

Pedal physically
pushes down on
master cylinder

Implement motor
and cable system
driven by Copley
Accelnet motor
controller
Mitch Leammukda
Master
Cylinder
Brake Pedal
Agile Robotics Site Visit
8/8/2008
8
Hydraulic Brake (cont.)
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
9
Parking Brake



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Pedal physically pulls
on cable to engage
parking brake
Hand lever releases
brake
Implement motor,
clutch, and cable
system to engage
Implement solenoid
and cable to disengage
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
10
Parking Brake (cont.)
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
11
Mast Actuation

Mini-Levers system
◦ Potentiometers
control DOFs




Lift
Tilt
Sideshifting
Fork positioning
◦ Forklift’s electronic
control unit (ECU)
reads voltages across
the potentiometers
and then controls the
mast
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
12
Mast Actuation (cont.)

Microcontroller (uC)
in between MiniLevers and ECU
◦ uC controlled by CPU
and then output
voltages to control
mast
◦ uC can accept output
from Mini-Levers and
then “relay” voltages
to ECU
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
13
System Integration – Next Steps

Controls Interface Modifications
◦ Design computer control capability of accelerator, transmission,
emergency stop, on-board electronics, etc.

Power Inverters
◦ Provide sufficient power to CPU, sensors, add’l motors, safety
indicators, networking components

Computers
◦ Process sensor data, perform planning and execution of maneuvers
◦ Shock-mounted to handle dynamic movement, bumps

Sensor Mounting
◦ Allow for proper data collection of variety of sensors, pointing in
different directions
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
Timeline
apr 08
aug 08
sep 08
nov 08
jan 09
Concepts of mechanical &
electrical modifications
All DBW elements transferred to
full-size prototype ready for
software testing and data collection
Additions & modifications for selfcontained autonomous platform
Complete all modifications for
autonomous capability
End-to-end capability demonstrated
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
mar 09
Schedule/Milestones

Sept. 30, 2008
◦ All DBW elements transferred to full-sized prototype ready for
software testing and data collection


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

Steering, hydraulic brake, and parking brake actuation
Mast, accelerator, transmission actuation
Baseline set of sensors mounted and wired
CANBus interface software reading vehicle data/states
Nov. 30, 2008
◦ Additions/modifications for self-contained autonomous platform
 Power inversion additions and wiring
 Controls CPU system mounted with network connections
 Preliminary human/autonomous handoff system

Jan. 31, 2009
◦ Complete all modifications for autonomous capability
 Robust safety/handoff system implemented
 Visible & audible annunciators functional

March 31, 2009 – end of Year 1
◦ End-to-end capability demonstrated
Mitch Leammukda
Agile Robotics Site Visit
8/8/2008
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