CIRP CARV Conference 2018 08-10 October 2018

Nantes, France

Digital twin for adaptation of robots’ behavior in flexible robotic assembly lines

Niki Kousi, Christos Gkournelos, Sotiris Aivaliotis, Christos Giannoulis, George Michalos, Sotiris Makris

Laboratory for Manufacturing Systems & Automation (LMS)Dept. of Mechanical Engineering & AeronauticsUniversity of Patras, Greecewww.lms.mech.upatras.gr

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Contents

▪ Introduction

▪ Hybrid production paradigm

▪ Digital twin infrastructure

• Resource Manager

• Sensor manager

• 3D Environment constructor

▪ Unified data model

▪ Automotive case study

▪ Conclusions

▪ Acknowledgments

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Introduction

Today – Tradition production Tomorrow – Future production

Production system transition to mass customization

Stationary resources – rigid line structure

Fixed control logic of the process

High cost – effort to make changes in the line-process

Market demand for higher product personalization

Need for multi product variants

Need for Flexible and reconfigurable production lines

Lead to

combined with Lead to

Lead to

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Hybrid production paradigm

How to enable the dynamic nature of this production paradigm ?

“Perception & skills to

automatically program and

execute multiple tasks”

“Human-Robot &

Robot-Robot

collaboration in a safe

way”

Mobile Product Platform (MPP)

Mobile Robot Platform (MRP)

“Enabling mobility on

products and resources”

Product & Process Perception

Environment Perception “Dynamic balancing and

redirecting to stations”

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Digital twin infrastructure

Resource Nodes

Resource

Manager

Sensor

Manager

Layout

Manager

3D environment

constructor

Unified

Data

Model

Sensor Nodes

3D Scene reconstructionArm Motion

Planner

Platform

Path Planner

Robot behavior

adaption

Digital Twin

CAD files

Execution Coordinator

CAD

Sensors

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Resource Manager

ROS Driver Driver

: Resource manager

MRP_1 Status topic

MRP_1 Location topic

MPP_1 Status topic

MPP_1 Location Topic

MPP_1MRP_1

: Status Monitoring

: Location Monitoring

: Status Monitoring

: Location Monitoring

ROS Topic Publisher

ROS Topic Publisher

ROS Topic Subscriber

ROS Topic Subscriber

ROS Topic Subscriber

ROS Topic Subscriber

• The registration of a new

resource into the production

system

• The storage of the appropriate

attributes based on the unified

resource model

• Realtime monitoring

❖ Resource location

❖ Resource execution status

The responsibilities of resource

manager are:

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Sensor Manager

ROS

Driver

rc_visard 65KinectMicroScan3rc_visard 160

ROS

Driver

ROS

Driver

ROS

Driver

ROS Topic Publisher

ROS Topic Publisher

ROS Topic Publisher

ROS Topic Publisher

: Sensor manager

rc_visard 160 topic

MicroScan3 topic

Kinect topicrc_visard 65 topic

: 2D-3D Sensor Data combination

Fused data topic

ROS Topic Subscriber

ROS Topic Subscriber

ROS Topic Subscriber

ROS Topic Subscriber

ROS Topic Subscriber

• The interfacing with the existing’s

sensors’ ROS drivers.

• The storage of the appropriate

configuration files based on the

unified sensor model

• Sensor data combination

for merging multiple, sensor data

into one topic

The responsibilities of sensor

manager are:

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Layout Manager

• The storage of the CADs files of

fixtures, parts and products.

• The creation of the .sdf files

containing the collisions and the

inertia attributes

• The relative positions between

parts and static fixtures

The responsibilities of layout manager are:

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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3D Environment Constructor

Generated Tf tree

3D Environment constructor

rc_visard URDF file

MRP URDF file

Product SDF file

TF topic tree

MPP URDF file

Kinect URDF file Laser Scanner URDF file

Fixtures SDF file

Sensors Manager

Layout s Manager

Re

sou

rce

s M

ana

ge

r

Publish tf data

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Unified world data model

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Automotive case study (1/3)

Station Task Resource Duration

S1 Pre-assembly of right damper Human 12 secs

S1 Load damper on comp. machine Human 5 secs

S1

Compression of right damper & Alignment / Nut insertion during the compression

Human –Comp. mach.

20 secs (human -8 secs)

S1 Load comp. damper on AGV Human 5 secs

S2 Pre-assembly of left damper Human 12 secs

S2 Load damper on comp. machine Human 5 secs

S2 Compression of right left & Alignment / Nut insertion during the compression

Human –Comp. mach.

20 secs (human -8 secs)

S2 Load comp. damper on AGV Human 5 secs

S3 Screwing machine connect each damper with one disk

Screwing machine

57 secs

S4 Cables / Screws Insertion Human 50 secs

• Assembly of the front suspension of a

passenger vehicle

• Involves handling, cabling insertion and

screwing operations – 4 workstations

• Manual assembly & 1 automated screwing

machine

• Challenges of the current set up

❖ Ergonomy: up to 480 dampers (6 Kg)

are lifted by human operators per shift

❖ Flexibility: the automated screwing

machine cannot handle all product

variants

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Automotive case study (2/3)

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Automotive case study (3/3)

MRP H/W configuration Online robot arm motion planning

3D Octomap

Online robot base path planning

Moving

obstacle

Integrated software components:

Online robot instruction with gestures

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Conclusions

The benefits of the proposed infrastructure for a production

system

✓ Robustness against the real-world uncertainty

✓ Generic enough to be applicable in various use cases

✓ Fast and easy integration of new resources

Future work

➢ Integration with the physical robotic set up

➢ Performance validation in the proposed infrastructure

➢ Integration with a high level decision mechanism for online

task re-allocation

Laboratory for Manufacturing Systems and Automation (LMS)Department of Mechanical Engineering and Aeronautics, University of Patras, Greece

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Acknowledgments

THOMAS

Mobile dual arm robotic workers with embedded cognition for

hybrid and dynamically reconfigurable manufacturing systems(Grant Agreement: 723616)

http://www.thomas-project.eu

http://www.thomas-project.eu/facebook

http://www.thomas-project.eu/youtube

http://www.thomas-project.eu/twitter

http://www.thomas-project.eu/googleplus

http://www.thomas-project.eu/linkedin

CIRP CARV Conference 2018 08-10 October 2018

Nantes, France

THANK YOU!

Laboratory for Manufacturing Systems & Automation (LMS)Dept. of Mechanical Engineering & Aeronautics

University of Patras, Greecewww.lms.mech.upatras.gr