Title
Characterizing Universal Reconfigurability of Modular Pivoting Robots
Abstract
We give both efficient algorithms and hardness results for reconfiguring between two connected configurations of modules in the hexagonal grid. The reconfiguration moves that we consider are "pivots", where a hexagonal module rotates around a vertex shared with another module. Following prior work on modular robots, we define two natural sets of hexagon pivoting moves of increasing power: restricted and monkey moves. When we allow both moves, we present the first universal reconfiguration algorithm, which transforms between any two connected configurations using $O(n^3)$ monkey moves. This result strongly contrasts the analogous problem for squares, where there are rigid examples that do not have a single pivoting move preserving connectivity. On the other hand, if we only allow restricted moves, we prove that the reconfiguration problem becomes PSPACE-complete. Moreover, we show that, in contrast to hexagons, the reconfiguration problem for pivoting squares is PSPACE-complete regardless of the set of pivoting moves allowed. In the process, we strengthen the reduction framework of Demaine et al. [FUN'18] that we consider of independent interest.
Year
DOI
Venue
2021
10.4230/LIPIcs.SoCG.2021.10
SoCG
DocType
Citations 
PageRank 
Conference
0
0.34
References 
Authors
0
10
Name
Order
Citations
PageRank
Hugo A. Akitaya1119.76
Erik D. Demaine24624388.59
Andrei Gonczi300.34
Dylan H. Hendrickson400.34
Adam Hesterberg547.07
Matias Korman617837.28
Oliver Korten701.35
Jayson Lynch802.70
Irene Parada902.03
Vera Sacristan109511.80