Evacuating Two Robots from Two Unknown Exits on the Perimeter of a Disk with Wireless Communication

Pattanayak, Debasish; Ramesh, H.; Mandal, Partha Sarathi; Schmid, Stefan

doi:10.1145/3154273.3154313

Cited by 18 publications

(9 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The relevance of the paper is modeled in real life situations where evacuation is critical and in which certain members of society are given priority over others due to class, hierarchical position or even demographic differences. In many research problems both the wireless and face-to-face models are reviewed for a small number as well as an asymptotically large number of robots [13,17,22].…”

Section: Related Workmentioning

confidence: 99%

Scatter Search on a Disk

Chopra¹

2021

Preprint

View full text Add to dashboard Cite

Consider a unit disk with two objects at unidentified locations. We examine the problem of two or more robots in search of both objects in the wireless communication model. We begin with two robots and both are needed to carry an object. Subsequently, we design several algorithms that describe robots trajectories in search of the objects. We were able to achieve a minimum worst-case search time of 6.7518 and a lower bound of 3 + π 2 . Additionally, we define two general cases and bound the worst-case search time for both. The first of the cases is for n ≥ 3 robots and an object can be moved by one robot. The second case is where we have n ≥ 3 robots and two robots are needed to carry an object. We achieve an upper bound of 1 + 2π n + sin (⌊n 2 ⌋ π n ) for the first case and an upper bound of 3 + 2π n + sin π n for the second case, with lower bounds of 2 + π n and 3 + π n respectively.

show abstract

Section: Related Workmentioning

confidence: 99%

Scatter Search on a Disk

Chopra¹

2021

Preprint

View full text Add to dashboard Cite

show abstract

“…Since the inception of 2 EVAC F2F in [1], numerous search and evacuation-type variants have emerged that studied different robot specs and/or number of searchers, different communication models, and different domains. Some notable examples include search and/or evacuation in the disk with more than 1 exits [29,30], in triangles [31,32], on multiple rays [33], in graphs [34,35], on a line with at least two robots [36,37] (generalizing the seminal result of [38]), with faulty robots [39][40][41] or with probabilistically faulty robots [42], with advice (information) [43], with priority specification on the searchers [44,45], with immobile agents [46,47], with time/energy trade-off requirements [48,49], with speed bounds [50], and with terrain dependent speeds [51], just to name some. The interested reader may also see the recent survey [52] that elaborates more on some selected topics.…”

Section: Related Workmentioning

confidence: 99%

A Multi-Objective Optimization Problem on Evacuating 2 Robots from the Disk in the Face-to-Face Model; Trade-Offs between Worst-Case and Average-Case Analysis

2020

View full text Add to dashboard Cite

The problem of evacuating two robots from the disk in the face-to-face model was first introduced by Czyzowicz et al. [DISC’2014], and has been extensively studied (along with many variations) ever since with respect to worst-case analysis. We initiate the study of the same problem with respect to average-case analysis, which is also equivalent to designing randomized algorithms for the problem. In particular, we introduce constrained optimization problem 2EvacF2F, in which one is trying to minimize the average-case cost of the evacuation algorithm given that the worst-case cost does not exceed w. The problem is of special interest with respect to practical applications, since a common objective in search-and-rescue operations is to minimize the average completion time, given that a certain worst-case threshold is not exceeded, e.g., for safety or limited energy reasons. Our main contribution is the design and analysis of families of new evacuation parameterized algorithms which can solve 2EvacF2F, for every w for which the problem is feasible. Notably, the worst-case analysis of the problem, since its introduction, has been relying on technical numerical, computer-assisted calculations, following tedious robot trajectory analysis. Part of our contribution is a novel systematic procedure, which given any evacuation algorithm, can derive its worst- and average-case performance in a clean and unified way.

show abstract

“…Most results were obtained for evacuation from the disk with wireless communication, i.e., for robots that can exchange information at all times. Czyzowicz et al [20] and Pattanayak et al [11] consider evacuation with multiple exits and known positions of the exists relative to each other. Lamprou et al [18] consider two robots of different speeds.…”

Section: Related Workmentioning

confidence: 99%

Evacuating Two Robots from a Disk: A Second Cut

Disser

Schmitt

2019

Structural Information and Communication Complexity

View full text Add to dashboard Cite

We present an improved algorithm for the problem of evacuating two robots from the unit disk via an unknown exit on the boundary. Robots start at the center of the disk, move at unit speed, and can only communicate locally. Our algorithm improves previous results by Brandt et al. [CIAC'17] by introducing a second detour through the interior of the disk. This allows for an improved evacuation time of 5.6234. The best known lower bound of 5.255 was shown by Czyzowicz et al. [CIAC'15].

show abstract

Evacuating Two Robots from Two Unknown Exits on the Perimeter of a Disk with Wireless Communication

Cited by 18 publications

References 5 publications

Scatter Search on a Disk

Scatter Search on a Disk

A Multi-Objective Optimization Problem on Evacuating 2 Robots from the Disk in the Face-to-Face Model; Trade-Offs between Worst-Case and Average-Case Analysis

Evacuating Two Robots from a Disk: A Second Cut

Contact Info

Product

Resources

About