Jeffrey Gould

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Robot Mobility in Harsh Environments Using
Hydraulically Actuated Articulated Limbs

• Jeffrey Gould

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Outline

• Objectives
• Criteria and Constraints
• Design Overview
• Some Specifics
• In the Works

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Objectives

• To Develop a Novel Approach to Robot Locomotion
  Suitable for Urban Search and Rescue
• Design and Construct Critical Subsystems in a
  Prototype
• Emphasis on Kinematics and Controls

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Criteria and Constraints

• Strong Enough to Force Its Way Through Rubble
• Physically Robust Enough to Survive in Harsh
  Environment
• Stable and Robust Control System
• Untethered

• Small to Penetrate Rubble Without Adversely
  Affecting Structures Stability
• Lightweight to Reduce Power Demands
• Simple to Set-Up and Operate
• Non-Hazardous

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Design Overview
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Burrowing Inspiration
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Basic Arm Kinematics

• Two Joints
• Hydraulically Operated
• 180 Not Possible

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More Inspiration

• Only Need 135
• Not Unique
• Possible to Optimize

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Optimization

• Shortest/Smallest
• Cost
• Bulk
• Weight
• Flow
• Rotation Requirement
• Torque Requirement

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Equations
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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Heuristic Approach
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How to Pick dmin?

• Determines Force Against Environment
• Mission Requirements
• More Information on Complete Robot
• Using 300-500 Pounds at Tip
• Interference

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Joint Specifics

• Find Rod End
• Find Bearing
• Check For Clearance

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Bearings
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Bearings
Fc
Fe
Fr
R
L
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Tubing
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In the Works

• Valves
• Pump
• Folding Design
• Balance
• Sensors

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Folding Design

• Might be advantageous for locomotion
• Needed to get through doors

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Balance

• Tail Section
• Simple Rear Legs

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Sensors

• Joint Angle
• Optical Encoder
• Absolute
• Single Turn
• Pressure Sensors
• Strain Gages
• Whiskers/Proximity

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Questions?
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180 Concept
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Components