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Non-communicative robot swarming in the GUARDIANS project

J. Sàez-Pons

Lyuba Alboul

Veysel Gazi

Jacques Penders

8 January, RISE 08

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GUARDIANS project

© Jaime Alemany

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Contents

• Non-communicative robot swarming• Potential functions method• Simulation results• Conclusions• Future work

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Non-communicative robot swarming

• Robot formation and keeping

• No communication robot-robot

• No communication robot-human

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Method

• Social potential functions [Reif and Wang 99]

Each robot Ri calculates a Force Fi, which is the generator of the new velocity vector of the robot

• Assumptions:

Each robot can distinguish between obstacles, humans and other robots

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Robot-robot potential function

Where position vector,

euclidean norm, and

is the vector from robot i to j

ij

robot-robot potential function

0.0

1.0

2.0

3.0

4.0

5.0

6.0

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0

rij

Frr

(rij

)

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Robot-obstacle potential function

i

p

Where position vector,

euclidean norm, and

is the vector from robot i to p

robot-point potential function

0.0

1.0

2.0

3.0

4.0

5.0

6.0

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0

rij

Urp

(rij

)

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Robot-human potential function

h

i

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Artificial potential function (APF)

ij

p

hRobot-Human

Robot-Robot

Robot-Obstacle

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Simulation results

-Video

- Player software (robot device interface)- Stage (2D multiple robot simulator)- Erratic model equipped with Hokuyo laser rangefinder

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Simulation results

-Video

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Simulation results

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Conclusions

• Formation generation around the fire fighter with no communication between team components

• Potential field method suitability

• Robot-human team navigation

• Swarm obstacle avoidance

• Flexibility– Number of robots

– Robust to failures of individual robots

• Problems using APF– Local minima

– Overwhelmed situations

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Future work

• More complex scenarios:– More obstacles

– Narrow corridors

– Doors

• Combination of different control behaviours– Wall-following

– Lost robot situation

– …

• Study other attraction/repulsion potential functions

THANK YOU!