Multirobot ManipulationMultirobot Manipulation

Ramon Costa CastellóRamon Costa CastellóInstitut d’Organització i Control de Sistemes Institut d’Organització i Control de Sistemes

Industrials (IOC)Industrials (IOC)

Universitat Politècnica de Catalunya Universitat Politècnica de Catalunya (UPC)(UPC)

IntroductionIntroduction

MotivationsMotivations

Multirobot Manipulation Multirobot Manipulation

AdvantagesAdvantages Load Capacity IncreaseLoad Capacity Increase

Dexterity ImprovementDexterity Improvement

Flexible ObjectsFlexible Objects

Environment

Dynamics and kinematics

Low level control loop

Path Planning

Trajectory Planning

Adaptation

Workspace

force

Robot Robot System System

ProgramminProgrammingg

Positionvelocity

path

trajectory

Experimental ConstraintsExperimental Constraints

Position controlled Position controlled ManipulatorsManipulators

Force SensorsForce Sensors

Rigid ObjectsRigid Objects

Rigid GraspingRigid GraspingR(z)Hd H

Experimental SetupExperimental Setup Experimental Setup: Experimental Setup: Work cell Work cell

composed by two RX-90 Stäubli composed by two RX-90 Stäubli manipulators (in ALTER mode), each manipulators (in ALTER mode), each manipulator having a JR3 force sensor on manipulator having a JR3 force sensor on its wristits wrist

RX-90 RX-90 JR3 JR3

PC-QNX

ISA BUS

Serial Line Controller

Internal ForcesInternal Forces Coordinated Manipulation Coordinated Manipulation

may apply undesired may apply undesired forces over manipulated forces over manipulated objectobject

Internal forces sourcesInternal forces sources inaccurate modellinginaccurate modelling lack of synchronizationlack of synchronization

GoalGoal Keep internal forces under Keep internal forces under

controlcontrol Desired load distributionDesired load distribution

Classical ApproachesClassical Approaches

Environm

ent

Robot i

control

Robot j

Environm

ent

Robot i

control

Robot j

control

Hybrid Control•Force-position Decomposition•Centralized approach•Structured Environments•Explicit Control

Impedance behaviour•Relation Between force and position•Decentralized approach•Unstructured environments•Implicit Control

Workspace ReductionWorkspace Reduction

Kinematics Kinematics Constraints Reduce Constraints Reduce Multirobot Workspace Multirobot Workspace (only on cooperative (only on cooperative manipulation).manipulation).

Workspace defined Workspace defined by implicit equations.by implicit equations.

Detailed TopicsDetailed Topics

Workspace Analysis ResultsWorkspace Analysis Results Hybrid Control ResultsHybrid Control Results Impedance Control ResultsImpedance Control Results