Anarchy, state, and utopia

Swarm robotics is an approach to collective robotics that takes inspiration from the self-organized behaviors of social animals. Through simple rules and local interactions, swarm robotics aims at designing robust, scalable, and flexible collective behaviors for the coordination of large numbers of robots. In this paper, we analyze the literature from the point of view of swarm engineering: we focus mainly on ideas and concepts that contribute to the advancement of swarm robotics as an engineering field and that could be relevant to tackle real-world applications. Swarm engineering is an emerging discipline that aims at defining systematic and well founded procedures for modeling, designing, realizing, verifying, validating, operating, and maintaining a swarm robotics system. We propose two taxonomies: in the first taxonomy, we classify works that deal with design and analysis methods; in the second taxonomy, we classify works according to the collective behavior studied. We conclude with a discussion of the current limits of swarm robotics as an engineering discipline and with suggestions for future research directions.

/pdf/swarm-robotics-a-review-from-the-swarm-engineering-46mfc058e6.pdf

Swarm robotics: a review from the swarm engineering perspective

This self-contained introduction to the distributed control of robotic networks offers a distinctive blend of computer science and control theory. The book presents a broad set of tools for understanding coordination algorithms, determining their correctness, and assessing their complexity; and it analyzes various cooperative strategies for tasks such as consensus, rendezvous, connectivity maintenance, deployment, and boundary estimation. The unifying theme is a formal model for robotic networks that explicitly incorporates their communication, sensing, control, and processing capabilities--a model that in turn leads to a common formal language to describe and analyze coordination algorithms.Written for first- and second-year graduate students in control and robotics, the book will also be useful to researchers in control theory, robotics, distributed algorithms, and automata theory. The book provides explanations of the basic concepts and main results, as well as numerous examples and exercises.Self-contained exposition of graph-theoretic concepts, distributed algorithms, and complexity measures for processor networks with fixed interconnection topology and for robotic networks with position-dependent interconnection topology Detailed treatment of averaging and consensus algorithms interpreted as linear iterations on synchronous networks Introduction of geometric notions such as partitions, proximity graphs, and multicenter functions Detailed treatment of motion coordination algorithms for deployment, rendezvous, connectivity maintenance, and boundary estimation

/pdf/distributed-control-of-robotic-networks-a-mathematical-1q6nfcvi2l.pdf

Distributed Control of Robotic Networks: A Mathematical Approach to Motion Coordination Algorithms

(i) You are allowed to freely download, share, print, or photocopy this document. (ii) You are not allowed to modify, sell, or claim authorship of any part of this document. (iii) We thank you for any feedback information, including suggestions, evaluations, error descriptions, or comments about teaching or research uses.

http://carmenere.ucsd.edu/pdfs/DCRN-BulloCortesMartinez-bibliography.pdf

Distributed Control of Robotic Networks

This paper is concerned with the collective behavior of a group of n > 1 mobile autonomous agents, labelled 1 through n, which can all move in the plane. Each agent is able to continuously track the positions of all other agents currently within its "sensing region" where by an agent's sensing region is meant a closed disk of positive radius r centered at the agent's current position. The multi-agent rendezvous problem is to devise "local" control strategies, one for each agent, which without any active communication between agents, cause all members of the group to eventually rendezvous at single unspecified location. This paper describes two types of strategies for solving the problem. The first consists of agent strategies, which are mutually synchronized, in the sense that all depend on a common clock. The second consists of strategies, which can be implemented independent of each other, without reference to a common clock.

http://www.eeci-institute.eu/GSC2012/Photos-EECI/EECI-GSC-2012-M15/handout2/rendezvous/Rend.sync.cdc.pdf

The multi-agent rendezvous problem

We consider a collection of robots which are identical (anonymous), have limited visibility of the environment, and no memory of the past (oblivious); furthermore, they are totally asynchronous in their actions, computations, and movements We show that, even in such a totally asynchronous setting, it is possible for the robots to gather in the same location in finite time, provided they have a compass

/pdf/gathering-of-asynchronous-oblivious-robots-with-limited-76hdelwsj4.pdf

Gathering of Asynchronous Oblivious Robots with Limited Visibility

In this paper, we study the distributed coordination and control of a set of asynchronous, anonymous, memoryless mobile vehicles that can freely move on a two-dimensional plane but cannot communicate among themselves. In particular, we analyze the problem of forming a certain pattern and following a designated vehicle, referred to as the leader, while maintaining the pattern: the flocking problem. We provide an algorithm to solve the flocking problem, together with theoretical considerations on its correctness and applicability, and numerical simulation showing the actual behavior of the algorithm. We also propose two variants of the algorithm sporting a more stable convergence, and analyze how different conditions on the equipment available to the vehicles and on the amount of knowledge they share affect the kind of patterns that can be formed.

Coordination without communication: the case of the flocking problem

In this paper we address the problem of mobile agents searching for a highly harmful item (called a black hole) in a ring network. The black hole is a stationary process that destroys visiting agents upon their arrival without leaving any observable trace of such a destruction. The task is to have at least one surviving agent able to unambiguously report the location of the black hole. We consider different scenarios and in each situation we answer some computational as well as complexity questions. We first consider agents that start from the same home base (co-located). We prove that two such agents are necessary and sufficient to locate the black hole; in our algorithm the agents perform O(n log n) moves (where n is the size of the ring) and we show that such a bound is optimal. We also consider time complexity and show how to achieve the optimal bound of 2n - 4 units of time using n - 1 agents. We generalize our technique to establish a trade-off between time and number of agents. We then consider the case of agents that start from different home bases (dispersed) and we show that if the ring is oriented, two dispersed agents are still necessary and sufficient. Also in this case our algorithm is optimal in terms of number of moves (Θ(n log n)). We finally show that if the ring is unoriented, three agents are necessary and sufficient; an optimal algorithm follows from the oriented case.

Mobile Search for a Black Hole in an Anonymous Ring

Consider a networked environment, supporting mobile agents, where there is a black hole: a harmful host that disposes of visiting agents upon their arrival, leaving no observable trace of such a destruction. The black hole search problem is the one of assembling a team of asynchronous mobile agents, executing the same protocol and communicating by means of whiteboards, to successfully identify the location of the black hole; we are concerned with solutions that are generic (i.e., topology-independent). We establish tight bounds on the size of the team (i.e., the number of agents), and the cost (i.e., the number of moves) of a size-optimal solution protocol. These bounds depend on the a priori knowledge the agents have about the network, and on the consistency of the local labelings. In particular, we prove that: with topological ignorance Δ+1 agents are needed and suffice, and the cost is Θ(n
 2), where Δ is the maximal degree of a node and n is the number of nodes in the network; with topological ignorance but in presence of sense of direction only two agents suffice and the cost is Θ(n
 2); and with complete topological knowledge only two agents suffice and the cost is Θ(n log n). All the upper-bound proofs are constructive.

/pdf/searching-for-a-black-hole-in-arbitrary-networks-optimal-4emm9xmx61.pdf

Searching for a black hole in arbitrary networks: optimal mobile agents protocols

https://www.site.uottawa.ca/~flocchin/Papers/TCS-self-deployment.pdf

Giuseppe Prencipe

Papers

Gathering of Asynchronous Oblivious Robots with Limited Visibility

Coordination without communication: the case of the flocking problem

Mobile Search for a Black Hole in an Anonymous Ring

Searching for a black hole in arbitrary networks: optimal mobile agents protocols

Self-deployment of mobile sensors on a ring