networked control systems vincenzo liberatore. today: cyberspace interact with remote virtual...
TRANSCRIPT
Today: CyberspaceToday: Cyberspace
Interact with remote virtual environment– On-line social activities
Communicate with co-workers, friends
– On-line search and information gathering– Disaster Recovery Networks– Distributed multimedia, games– E-commerce:
Buy books, CDs, computers Dump stock shares
Tomorrow: Cyber+PhysicsTomorrow: Cyber+Physics
Affect a remote physical environment– Hazardous environments– Terrestrial, space exploration– Distributed manufacturing– Remote diagnostic and troubleshooting– Experimental facilities
E.g., microgravity fluid dynamics
– Home robotics
Enabling TechnologiesEnabling Technologies
Embedded computing– Embed computers in the physical world
Pervasive networking– Interconnect them
Control theory and robotics– Physics-software interface
ChallengesChallenges
Remove dependency on– Precise environment models– Quality-of-Service provisioning
Software that is– Distributed– Adaptive and evolvable– Secure and safe (e.g., stability)– Remotely re-programmable
ObjectivesObjectives
Manipulation tasks– E.g., collect and manipulate a specimen from Mars
surface– Contact operations
Energy exchanged between robot and environment Results in physical change in environment state
– Safety: Force or kinematics constraints
Remote supervision
Distributed ControlDistributed Control
Natural admittance control– Virtual Attractors– Locally encapsulates real-time constraints
Multi-agent distributed system– Software components, autonomous, adaptable,
knowledgeable, mobile, collaborative, persistent
Supervisory control and tele-operation Evolvable software
DemonstrationDemonstration
Engineer, using a C# interface, loads a high-level command into the Virtual Supervisor (VS).
Wide-area Network
The VS then splits the command into pieces and send them to the
VR
VR
VR VR
VRVR
VR
Based on data obtained by the other VR’s, the robot is controlled directly by a single VR.
Virtual Robots (VR’s) residing on the network.
BenefitsBenefits
Supervisory control– Beyond tele-operation and autonomy
Dynamic reconfiguration– Task-oriented reconfiguration– Plug-and-play– Fault-tolerance– Survivability– Extensibility
Networked Control SystemsNetworked Control Systems
Traditional view
CONTROL SYSTEM+
-
Networked control system
INTERNET
CONTROL SYSTEM+
-
FoundationsFoundations
Toward a theory of networked control– Mathematical underpinnings – Established operation principles– Patterns and pitfalls
Core factors– System dynamics
E.g., output of open loop system
– Network dynamics E.g., packet forwarding, losses, delays, jitter
Networked control systems
AcknowledgmentsAcknowledgments
Faculty– Vincenzo Liberatore, Wyatt S. Newman,
Michael S. Branicky, Steve P. PhillipsStudents
– Adam Covitch, Ahmad Al-HammouriAlumni
– David Rosas