Mech 328 Team

1
Mech 328 Team 4
Angela Melick, Brendan Jay, Jon Leskewich, Dave
MacCallum

• Alternative Actuators Project

November, 2005 University of British Columbia
2
Introduction
?
A backhoe without hydraulic actuators?
3
Project Scope
Environmentally Sensetive
Rivers and Floods
Explosion Risk
Urban
Applications for backhoe with alternative
actuators
4
Problem Statement

• No hydraulic actuators
• Same digging power
• Limited modification

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Concepts

• Cable Actuators

• Robotic Actuators

• Power Screw Actuators

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Concepts
Cable Actuators

• Pros

• Cons

O

• Maintenance
• Cost
• Power
• Ease of Use
• Ease of Design
• Environmental

P
O
O
O
P
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Concepts
Robotic Actuators

• Pros

• Cons

P

• Maintenance
• Cost
• Power
• Ease of Use
• Ease of Design
• Environmental

O
O
P
O
P
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Concepts
Power Screws

• Pros

• Cons

P

• Maintenance
• Cost
• Power
• Ease of Use
• Ease of Design
• Environmental

O
P
P
P
P
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Selected Concept
Weighted Decision Matrix

• Power Screws

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Selected Concept
Actuator Details

• R075 E-stick
• 40kN for 5.50kW
• 6.72 m/min
• Casing Removed

• R250 - Stick
• 275kN for 9.50kW
• 5.52 m/min

• R225 - Bucket
• 175kN for 5.50kW
• 6.72 m/min

• R250 - Boom
• 350kN for 9.50kW
• 5.56 m/min

• R150 - Swing
• 125kN for 5.50kW
• 5.56 m/min

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Selected Concept
Actuator Features

• Load sensing safeties
• Quick manufacture
• 60dB operating
• Many connection and motor orientation options
• Options for faster actuators at additional cost.

12
Selected Concept
Modifications

• Replace Hydraulic actuators with power-screw
  actuators
• Two connections redesigned
• Add stand-alone generator

13
Selected Concept
Calculations

• Speed Volumetric Flow Rate / Bore Area
• Vf/(piD2/4) 11.0m/min
• Force Required
• F P(pi/4)d2

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Selected Concept
Comparisons

• Simultaneous Actuator Motion
• Slower Actuator Speed
• Power Gain in Boom, Stick, and Bucket
• Power Loss in E-stick and Swing
• Much Quieter Operating Noise
• Same power on push and pull

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Selected Concept
Power Supply Options and Cost Estimates

• Existing Diesel Engine
• External Generator
• For quiet operation
• 29kW MMG 35 John Deere Generator

• 244 404.74 CAD
• 25 50 000 per actuator
• 2500 for contract work ea.

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Summary
Dont sacrifice power!

• Same Power

• Low Noise

• Limited Modification

• Similar Range of Motion

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Thank You!