Swarm robotics is an approach to controlling large groups of robots inspired by social insects like ants and bees. It emphasizes emergent behaviors from local interactions between relatively simple robots with only local sensing and communication. This allows for properties like robustness, flexibility, and scalability needed for deploying many robots. Swarm robotics systems consist of many homogeneous robots that are not very capable individually but can collectively perform tasks through self-organization.

2. What is Swarm Robotics?
 Yet another novel approach to the control of large
group of robots!
 Study of multi-robot coordination strategies inspired
from social insects.
 Engineering self-organization in physically embodied
swarms.
 Application of Swarm Intelligence to the control of a
group of robots.

3. What’s novel and desirable in the
Swarm Robotics approach?
 Emphasis on the system-level functioning properties
observed in social insect systems:
 Robustness
 Flexibility
 Scalability
 Essential for deploying large numbers of robots.

4. Robustness
 Social insects can continue to operate despite large
disturbances.
 Redundancy
 Decentralized coordination
 Simplicity of the individuals
 Distributed sensing

5. Flexibility
 Social insects can offer modularized solutions to tasks
of different nature by utilizing different coordination
mechanisms.

6. Flexibility – same swarm, different
tasks
 Foraging
 Prey retrieval
 Chain formation

7. Scalability
 Social insects are observed to be able to operate under
a wide range of group sizes. That is, coordination
mechanisms are rather independent of the number of
individuals in the group.

8. Finally… a definition
 Swarm robotics is the study of how large number of
relatively simple physically embodied agents can be
designed such that a desired collective behavior emerges
from the local interactions among agents and between the
agents and the environment.

9. Criteria for Swarm Robotic systems
 A swarm robotic system should consist of
 large numbers of robots,
 few homogeneous groups of robots,
 robots that are relatively incapable or inefficient,
 robots with only local sensing and communication
abilities.

10. 0 - Individuals should be robots!
 Individuals should be autonomous robots.
 Individuals should
 be situated and autonomous
 be able to physically interact
 Mobility of individuals is sufficient, but not required.
 Metamorphic robotic systems?
 Yes
 Sensor networks?
 No

11. 1 - Large number of robots
 The study should be relevant for the coordination of
large numbers of robots.
 Why relevancy?
 How large is “large”?

12. 2 - Few homogeneous groups of
robots
 The robotic system should consist of few
homogeneous groups and that the number of robots in
each group should be large.
 Teams are not swarms.
 Hierarchical robotic systems (for instance swarms with
a “designated queen”) are less `swarm robotic’.
 What’s a homogeneous group?
 How about individual adaptation?

13. 3 - Relatively incapable of
inefficient robots
 The robotic system should utilize relatively incapable or
inefficient robots with respect to the task at hand.
 The robots should have difficulties in carrying the task on their
own.
 The deployment of a group of robots should improve the
performance of system.
 The deployment of a group of robots should improve the robustness
of the system.

14. 4 - Robots with only local sensing
and communication abilities
 For coordinating their actions, the robots should
utilize only local sensing and communication
capabilities.
 Locality promotes scalability.
 Existence of global communication channels not used
for coordination among the robots does not violate.

15. Sources of inspiration
 Self-organizing natural systems
 Social insect systems: ants, termites, wasps, bees,
cockroaches, locusts…
 Animals with social behaviors: penguins, birds, fish,
sheep...
 Unicellular organisms: Amoebae, bacteria, viruses…
 Artificial self-organizing systems
 Self-assembly of materials

16. Aggregation of amoebae into slime
mould
 When food is abundant,
amoebae (D. discoideum)
acts independently of
others, feeding and
multiplying (Bonner;1967,
Goldbeter;1996).
 When food supply is
depleted amoebae release
cAMP ( a chemo-attractant
for amoeba) into the extra-
cellular environment.
 Amoebae aggregate
forming a slug, a multi-
cellular organism which
can move and sporulate.
Summarized from Self-Organization in Biological
Systems by Scott Camazine, Jean-Louis
Deneubourg, Nigel R. Franks, James Sneyd,
Guy Theraulaz, and Eric Bonabeau

17. Quorum sensing in bacteria
 Bacteria seem to have
interesting communication
mechanisms to increase their
survival.
 V. fischeri produces light
when its population reach a
critical size.
 V. cholarae delays the
production of virulence factor
until they reach a certain
mass, to ensure a successful
infection against the
infection system.
 Recent studies show that
bacteria use certain auto-
inducers to detect their
density in the environment.
B.L. Bassler, How bacteria talk
to each other: regulation of
gene expression by
quorum sensing. Current
Opinions in Microbiology
1999 Dec;2(6):582-7.

18. Information exchange in bacteria
 Bacterial colonies can be more resistant to antibiotics than
bacteria living in suspension!
 Hypothesis: Bacteria form a “genomic web” communicating
with each other:
 Inducive communication: a chemical signal triggers a certain action
in other bacteria.
 Informative communication: the message received is interpreted by
the cell, and its response is determined by its history as well as its
current state.

19. Self-assembly
 Self-assembly: self-organization by making physical bond formation
 Individuals lose some of their motility. This creates some interesting
dynamics. Social insects and breakable bonds in chemistry
 Self-assembly of materials is described as the “autonomous
organization of components into patterns or structures without
[external] intervention.” Whitesides and Grzybowski (Science; 2002)
 Self-assembly is a promising method for fabricating regular structures:
nano-scale self-assembly is promising for building large numbers of
micro- electro-mechanical systems (MEMS), improving the robotic
assembly processes.
19/29

20. Domain Of Application
 Following are some applications of Swarm Robotics:
 1.Tasks that are too dangerous
 2.Tasks that cover a region
 3.Tasks that scale up or scale down in Time
 4.Tasks that require redundandcy

21. Conclusion
 Swarm robotics as a new approach to the control and
coordination of multi robot systems.
 It is supposed that a desired collective behavior
emerges from the interactions between the robots and
interactions of robots with the environment.
 The research of swarm robotics is to study the design
of robots, their physical body and their controlling
behavior.