Society and Technological Change Media Presentation about Darpa's BigDog. Dynamically stable Quadruped Robot.

1. Social Impact Of Technology
Destructive Technologies:
BigDog, the Rough-Terrain
Quadruped Robot
By Chris Sirett & Gabriel Karski
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2. Background
• Less than half the Earth's landmass is accessible to existing wheeled and tracked vehicles.
•This situation motivates the development of robot vehicles that use legs for their locomotion
• Boston Dynamics goal is to achieve animal-like mobility on rough and rugged terrain,
terrain too difficult for any existing vehicle.
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3. What Is BigDog ?
BigDog is a self-contained, unmanned, dynamically stable quadruped robot
• Developed as a robotic pack mule to accompany soldiers in terrain too rough for conventional
vehicle
• Funded By DARPA (Defense Advanced Research Foundation)
• Developed By Boston Dynamics in conjunction with NASA Jet Propulsion Laboratory and
Harvard University Concord Field Station.
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4. Size & Capabilities
• Size of a large dog; 1 meter long, 0.83 meter tall, 110 kg
• Can carry up to 155 kg
• Transverse Difficult Terrain
• Dynamically Stable
• Runs 6.4 km/h
• Can Climb a 35 degree incline
• Obstacle Tracking / Avoidance
• Autonomous Navigation (GPS)
• Follow the Leader Capable (LIDAR)
• Manual Control Capable (OCU)
• Follows Terrain Maps
• Can jump 1.1 meters
• Holds world record for a legged vehicle traveling 12.8 miles without stopping or
refueling
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5. BigDog’s Architecture
Gyro/IMU Heat Exchanger
Hip Engine/Pump
Computer
Knee
Actuators
Ankle
Leg Spring
Foot
Force Sensor
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6. Power Plant
Leopard go-kart engine
• One cylinder
• Two stroke
• Water cooled
• 9,000 rpm !!
• ~15 hp
• Electric starter
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7. Hydraulic System
Hydraulic System • Heat exchanger
• Variable displacement hydraulic pump • Various filters, manifolds,
(3,000 psi) accumulators, and
• Custom actuator package (x16) valves
– Low-friction hydrodynamic seals
– 2-stage electro-hydraulic servo-valve
– Position sensor
– Force sensor
Hydraulic
Actuator
Package
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8. Sensors
GPS LIDAR
(light detection
Battery Voltage and ranging)
Ring Laser
Gyro & Linear
Accelerometers Stereo Vision (pair
of camera’s)
Engine Temp
& Speed Joint angles
& forces
Hydraulic
Pressure, Flow
& Temp
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9. Sensory Perception
MEASUMENT 1,000 Hz update Frequency
TYPE LOCATION n
QUANTITY
Linear Pot Joint Displacements Knee, Hip, Ankle 16
Load Cell Actuator, ankle Forces Legs 16
Ammeter Servo Valve Current ebox 16
Sterio Vision Obstacles, optic flow, ground slope Body 3 Propioception
LIDAR Human Tracking Body 1
3 angular Rates
Gyro 3 Linear Accelerations (IMU) Body 6 Exeroception
Temperature Engine, Oil Temperature Body 3
Flow Oil Flow Body 4
Pressure Oil Pressure
Engine RPM
Body 2 Homeostasis
Govenor Battery Voltage Body 2
Total 69
Propioception: “Ones Own”. Provide information on the “feel” of a movement
Exeroception: Provide information on the outcome of a movement
Homeostasis: Is the property of a system that regulates its internal environment
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10. Onboard Computer
• PC104 stack
• Pentium 4 CPU
• QNX real-time OS
• Code: C++
• Custom I/O interface boards
• Functions Performed:
– Control
– Sensing
– Data Collection
– Communications
– Electric Power Distribution
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11. OCU (Operator Control Unit)
Operator Provides
High Level Control Visual Display Provides Operational and Engineering Data
Input Only.
• Steering Head Mounted
Display
• Speed
• Start/Stop Engine 900 Mhz
• Stand/Sit/Squat Antenna
• Walk/Trot/Jog
HMD
Electronics
Steering
Controller
OCU Computer
Onboard Control
System handles low Battery
level control
900 Mhz
• Stability Radio
• Reflex
• Obstacle Avoidance
08/08/12
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12. Adaptable
BigDog adapts to the terrain in two ways:
1.It adjusts body height and attitude to conform to the local terrain
2.Adjusts footfall placement to compensate for orientation of the robot body
and ground plane relative to gravity.
The control system leans the quadruped:
• forward while climbing slopes,
• backwards while descending slopes,
• sideways while walking along the contour line.
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13. Control – BigDog
Maintain Body Posture
• Control of body posture
through force control
Maintain Ground Contact
Lateral
• Force control through Velocity
compliant leg shock
Maintain Lateral Balance
• Places feet to control body
lateral velocity
BigDog Predicts lateral velocity
and acceleration for swing leg
placement
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14. Additional Controls
Motion
Estimates ground plane using history of leg kinematic data and odometry
• Adjusts posture to optimize leg strength while maintaining reach on terrain
• Uses traction control to avoid, detect and recover from foot slips
• Moves legs to avoid leg collisions
• Determines 3 dimensional motion using kinematic, inertial and visual odometry
Engine Power Control.
• Engine RPM regulated in response to actual and predicted load.
• Ground steepness, ground roughness, and lateral body velocity predict demand
Leg Collision Avoidance
• Adjacent legs have overlapping workspace
• Swing leg trajectories avoid hitting adjacent stance legs
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15. Navigation
 For Navigation BigDog uses:
• Stereo Vision
 Provides Visual Odometry
• GPS
 Provides Relative Position
• LIDAR
 Follow the leader Capability
• Terrain Maps
 Route Planning
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16. What is the Social Impact of BigDog and its Integrated
Technologies?
Each Technology on its own is
nothing revolutionary or ground
breaking
-The integration of the latest existing
technologies to create such a
complicated machine is an incredible
feat
-BigDog primarily a Military incentive
-Majority of funding from DARPA:
Defense Advanced Research Projects
Agency
-it’s an example of how Military
Technology is better funded and
more advanced than Industry
Technology
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17. Social Impact Continued…
Many technologies which have had a lasting impact on the world were first developed for
military including:
•Nuclear Energy Nuclear Energy today
as we know it started
•Computer Networking with the Atomic Bomb
•Laser Technology
BigDog will inevitably be armed with weapons for use of with Military Ground Operations
to accompany foot soldiers
Many other advanced military robot technologies are employed by the US army, such as
armed UAVs
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18. What does this mean for the good of our Planet?
 The development of more sophisticated military weapons technologies,
including integrated robotics makes the world a dangerous place
 Wide scale destruction and massacre possible in a matter of hours with
current weapons technology
 Next “World War”, or large scale conflict may threaten the world as we
know it
Let’s hope not….
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19. But there is hope…
 The upside: Many aspects of these advanced military technologies can be
used for good and for the advancement of society and the human race
 BigDog can be used in search & rescue operations, and it’s research and
production can lead to more sophisticated civil serving robots, such as:
 Robots for firefighting
 Autonomous robots for dangerous police operations
 Robots for dangerous work
A US Police
Surveillance UAV
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20. Final Thoughts
This is why it is vital to observe the social impact of these technologies
Society has a moral obligation to ensure such technologies do not get the
best of us, but are used for good.
Perhaps technology can save our planet too.
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21. END
Thanks for reading!
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22. References
 Osborn, K. (2007, September 15). Army records first uav kills. Retrieved from http
://www.armytimes.com/news/2007/09/army_UAV_kills_070915w/
 RT America. (2012, August 3). Domestic drone justice: Us court green-lights police uav
use. Retrieved from http://rt.com/usa/news/domestic-drone-court-ruling-743/
 Raibert, M., Blankespoor, K., Nelson, G., & Playter, R. (n.d.). Bigdog, the rough-terrain
quaduped robot. Retrieved from http://
www.bostondynamics.com/img/BigDog_IFAC_Apr-8-2008.pdf
 DARPA. (2012, February 7). Darpa’s legged squad support system (ls3) to lighten troops’
load). Retrieved from
http://www.darpa.mil/Our_Work/TTO/Programs/Legged_Squad_Support_System_
(LS3).aspx
 DRC Broad Agency. (2012, April 10). Darpa robotics challenge (drc). Retrieved from
http://www.darpa.mil/Our_Work/TTO/Programs/DARPA_Robotics_Challenge.aspx
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