Modular Snake ROS

Juan Leon, Laura Paez and Kamilo Melo{juan.leon,laura.paez,kamilo.melo}@km-robota.com

KM-ROBOTA Research Group, KM-ROBOTA S.A.S.Bogota - Colombia

www.km-robota.com.

ROSCon2013, Stuttgart, Germany

May 11, 2013

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Motivation

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Table of contents

1 Introduction. The Robot and the Framework Architecture

2 Interfacing the robot

3 Representing the robot - URDF

4 High Level Tools

5 Conclusions

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Introduction. The Robot and the Framework Architecture

Introduction, Lola-OP TM Robot

Figure: 16-DOF Lola-OPTM, Modular Snake Robot

http://www.km-robota.comhttp://www.robotsource.org

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Introduction. The Robot and the Framework Architecture

Introduction, Robot Structure

Zn+2

Zn-2

Zn-1

Zn

Zn+1

Figure: 16-DOF Lola-OPTM, structure

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Introduction. The Robot and the Framework Architecture

Introduction, Current Gait Control

Parameterized gaits

θ(n, t) =

Oo + AoSin

(n

λo+ ωot

), n odd

Oe + AeSin

(n

λe+ ωet + δ

), n even

(1)

Scripted Gaits.

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Introduction. The Robot and the Framework Architecture

Introduction

FunctionParameters

RobotLocomotion

CompoundSerpenoid Curve

Figure: 16-DOF Lola-OPTM, Controller Mapping

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Introduction. The Robot and the Framework Architecture

Introduction. Framework Architecture, Information Flow

Virt

ual E

nviro

nmen

t

V. Exo. Sensors

V. R

obot

ForwardKinematics

V. Prop.Sensors

Exo. Sensors

Rob

ot

ForwardKinematics

Prop.Sensors

DAQ

Plotting

User Input

High leveltaskinput

Controller Log

ProtocolSelector

Mes

sage

Pas

sing

Pro

toco

l Con

vert

er

Par

am

eter

ized

Scr

ipte

d

Look

-Up

Tabl

e C

ont

rol

Control Interfaces

FKPlotting

Tool

Animation

Figure: Simulation and Control Framework Architecture.

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Introduction. The Robot and the Framework Architecture

Introduction. Control Interfaces - Front-ends

Figure: Scripted and parameterized Gaits Front-ends.

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Introduction. The Robot and the Framework Architecture

Introduction. Physics Simulator Examples

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Introduction. The Robot and the Framework Architecture

Introduction. Log File and Real-Time Plotting

Virt

ual E

nviro

nmen

t

V. Exo. Sensors

V. R

obot

ForwardKinematics

V. Prop.Sensors

Exo. Sensors

Rob

ot

ForwardKinematics

Prop.Sensors

DAQ

Plotting

User Input

High leveltaskinput

Controller Log

ProtocolSelector

Mes

sage

Pas

sing

Pro

toco

l Con

vert

er

Par

am

eter

ized

Scr

ipte

d

Look

-Up

Tabl

e C

ont

rol

Control Interfaces

FKPlotting

Tool

Animation

Kde-KST

Figure: Plotting Capabilities

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Introduction. The Robot and the Framework Architecture

Introduction Architecture implemented with ROS

DAQ

Plotting

User Input

High leveltaskinput

Controller Log

ProtocolSelector

Mes

sage

Pas

sing

Pro

toco

l Con

vert

er

Par

am

eter

ized

Scr

ipte

d

Look

-Up

Tabl

e C

ont

rol

Control Interfaces

FKPlotting

Tool

Lola-OPTM

Kulebra-OPTM

NTNUKulKo

CMUUncle Sam

Lola-OP Simulator

KM-RoBoTa s.a.s.

Figure: Message Passing Protocol Converter implemented in ROS12 / 23

Interfacing the robot

Table of contents

1 Introduction. The Robot and the Framework Architecture

2 Interfacing the robot

3 Representing the robot - URDF

4 High Level Tools

5 Conclusions

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Interfacing the robot

Interfacing the Robot. The lola op middleware package

lola op middleware package features:

What we need to interface... just Dynamixel AX-12 actuators ?

... < depend package = ”dynamixel controllers”/ > ...

More Dependences (letting the door open)

Writing and Reading from the robot (establishing the Topic/s)

Qt interfaces → ROSlauch

Yes, it can be On-board too

Let’s look a simple Demo ...

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Representing the robot - URDF

Table of contents

1 Introduction. The Robot and the Framework Architecture

2 Interfacing the robot

3 Representing the robot - URDF

4 High Level Tools

5 Conclusions

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Representing the robot - URDF

Representing the Robot. URDF.xml

Figure: Fully Featured/Robust Lola-OPTM URDF

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High Level Tools

Table of contents

1 Introduction. The Robot and the Framework Architecture

2 Interfacing the robot

3 Representing the robot - URDF

4 High Level Tools

5 Conclusions

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High Level Tools

High Level Tools. Rviz visualization

Figure: Lola-OPTMin Rviz, Open loop gait controller

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High Level Tools

High Level Tools. TF

Figure: Using TF to implement the Floating Body Frame of Reference in SnakeRobots

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High Level Tools

High Level Tools. Remote Operation

Take the control, write the message, send it, move the real robot, gatherinfo, send it back, decode it, Rviz and visualize what is going on.

As simple as Bagfiles...

TCP/IP, from LAN → to Internet

What about Real Time ??

Let’s look another simple Demo ...

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Conclusions

Conclusions

Integration with Lola-OPTMRobot Architecture(each block as a ROSnode)

High Level Tools aid, Open issues to explore

What about MoveIt ?? (ROSCon2014...Maybe?)

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Conclusions

Conclusions

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Conclusions

Questions?

Thank you!

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