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

2Interfacing the robot

3

Representing the robot - URDF

4High Level Tools

5Conclusions

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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.com
http://www.robotsource.org

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Introduction. The Robot and the Framework Architecture

Introduction, Robot Structure

Zn+1
Zn-1
Zn-2
ZnZn+2

Figure: 16-DOF Lola-OPTM , structure

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Introduction. The Robot and the Framework Architecture

Introduction, Current Gait Control

Parameterized gaitsn
Oo + Ao Sin+ ωo t , n odd λo
θ(n, t) =n+ ωe t + δ , n evenOe + Ae Sinλe(1)Scripted Gaits.

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Introduction. The Robot and the Framework Architecture

Introduction

Function
ParametersCompound
Serpenoid Curve

Robot
Locomotion

Figure: 16-DOF Lola-OPTM , Controller Mapping

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Introduction. The Robot and the Framework Architecture

Introduction. Framework Architecture, Information Flow

ProtocolSelectorAnimation

DAQ

ForwardKinematics

Robot

Look-Up
Table Control

ScriptedControl Interfaces

Plotting

Prop.
SensorsExo.
Sensors

ForwardKinematics
V. Prop.
Sensors

Virtual Environment

Log
Message Passing
Protocol Converter

FKPlotting
Tool

Parameterized

User
Input

Controller

V. RobotHighleveltask
input

V. Exo.
Sensors

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

Kde-KST

ProtocolSelector

Animation

DAQ

ForwardKinematics

Robot

Look-Up
Table Control

ScriptedControl Interfaces

Plotting

Prop.
SensorsExo.
Sensors

ForwardKinematics
V. Prop.
Sensors

Virtual Environment

Log
Message Passing
Protocol Converter

FKPlotting
Tool

ParameterizedUserInput

Controller

V. Robot

Highlevel
task
input

V. Exo.
Sensors

Figure: Plotting Capabilities
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Introduction. The Robot and the Framework Architecture

Introduction Architecture implemented with ROS

Highleveltask
input

Log
Message Passing
Protocol Converter

FK
Plotting
Tool

Lola-OP
Simulator

Plotting

DAQ

Scripted

Look-Up
Table Control

Control Interfaces
Parameterized

User
Input

Controller

CMU
Uncle
Sam

ProtocolSelector

Lola-OPTM
Kulebra-OPTM

NTNU
KulKo

KM-RoBoTa s.a.s.

Figure: Message Passing Protocol Converter implemented in ROS
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Interfacing the robot

Table of contents1Introduction. The Robot and the Framework Architecture

2Interfacing the robot

3

Representing the robot - URDF

4High Level Tools

5Conclusions

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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

2Interfacing the robot

3

Representing the robot - URDF

4High Level Tools

5Conclusions

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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

2Interfacing the robot

3

Representing the robot - URDF

4High Level Tools

5Conclusions

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High Level Tools

High Level Tools. Rviz visualization

Figure: Lola-OPTM in 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 Snake
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High Level Tools

High Level Tools. Remote Operation

Take the control, write the message, send it, move the real robot, gather
info, 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

ConclusionsIntegration with Lola-OPTM Robot 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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