urban search and rescue 2007 general robotics 2007
TRANSCRIPT
Purpose• Carnegie Urban Rescue Force (CURF) has
started a initiative with the General Robotics Class of Spring 2007 to develop a fleet of highly compatible robots to help in the rescue effort.
Introduction
Design Criteria• Size Constraints
– Width: 6.0”– Depth: 8.5”– Height: 6.0”– Includes the vision system
• Tele-operation
• Vision System
• Extra Parts– Extra LEGO motor– $50 spending limit for LEGO parts
Introduction
High Level Overview• Write a Proposal March 21
• Checkpoint March 28
• Demonstration April 3
• Finalists April 4
• Poster April 9
• Self-Evaluation April 9
Tasks
Design Proposal• Write-up:
– Basic schematics– Descriptions– Special features– Obstacles– Climbing– Steering– Controllability
• Hand in by Tuesday, March 21st, 2007• Following outline is Highly Recommended.• Note: You cannot continue on with the
prototyping phase if your design proposal does not meet these requirements
Tasks
Common Difficulties
• Rubble and debris
• Collapsed objects
• Unstable structures
• Narrow hallways
• Obstacles
• Stairs
Tasks
Designing Good Robot Platform for Adverse Terrain
• Drive trains revisited• Tank Treads• Differential drive configurations• Center of Gravity• Mechanical Robustness• Suspensions• Testing
Mechanical
Drive Trains Revisited
• High-torque situations
• Back driving
• Foreign objects
• Weak links
Mechanical
Tank Treads
In the past, people forgot:
• Slack on top or bottom depending upon location of driven wheel
• Idler on top of tread can increase tension and area of drive wheel in contact with tread
Mechanical
Center of Gravity
•Masses–Handy Board–LEGO motors–Added mass (batteries, fishing weights, etc.)
•High CG is bad•Consider CG in relation to length and width•Traction
Mechanical
Mechanical Robustness
• Masses
• Internal forces
• Odd forces
• No parts sticking out
• Zip Ties
Mechanical
Suspensions
• 1st: Wheel/track suspension – squishyness of wheels– span of tracks
• 2nd: Active Dampening Suspensions– Tube things in kits– LEGO shock absorbers– Random foam, springs
• 3rd: Passive suspensions
Mechanical
Testing
• Torque Tests• Stall drive wheels • Hill Tests • Various terrain• Ground clearance• Break-over angle• Ridges
Mechanical
Control and Control Issues
• Robot has 1st person perspective
• Pilot has 3rd person perspective (sometimes occluded)
• Moveable Camera
• Where to put intelligence?
• Autonomy?
Controls
Control: Robot Intelligence
• Robot has encoders– go(int inches)– turn(int degrees)
• Ground sensors
– feelers
• Inclination sensors– mercury switches– rolling ball inclinometers, – accelerometers
• Internal sensor • Self-diagnostics
Controls
Control: Robot Autonomy
• Autonomous functions to deploy equipment
• Autonomously navigate occluded areas (i.e. wall following)
• Automate compounded functions such as expanding
Controls
“Smart Mechanism”• Mechanisms that compound DOFs
– Can do different things depending on which way turned
• Release mechanisms
• Expanding Mechanisms
• Locking Mechanisms– Can lock an expansion or an appendage
into position
• E-Mail me (and other TAs) for consulting
Controls
Neat Ideas
•Marsupial Robots–Robin Murphy, USF
•Shape Reconfiguring robots–Inuktun.com
•Asymmetry•NASA Rovers
•Current off road vehicle examples
–Land Rover–Jeep–Hummer–Moon Rover–Mars Rovers–ATVs–The Animal (ok, old)–Other Toys
Controls
Design Proposal?
• Qualitative analysis– Mobility, user friendliness, coolness
• Quantitative analysis– Top speed, ground clearance, torque
• For the proposal, we would like you to think numerically.
Q&A
Prototype Evaluation?
• 6 of the 8 checkpoints
• Ability to move and turn,
• Use the camera
• Surmount various obstacles.
• None of these require autonomy.
• This must be done during lab hours.
• March 28th at 8pm (the latest)
Q&A