---
_id: '62285'
abstract:
- lang: eng
  text: 'The sliding square model is a widely used abstraction for studying self-reconfigurable
    robotic systems, where modules are square-shaped robots that move by sliding or
    rotating over one another. In this paper, we propose a novel distributed algorithm
    that enables a group of modules to reconfigure into a rhombus shape, starting
    from an arbitrary side-connected configuration. It is connectivity-preserving
    and operates under minimal assumptions: one leader module, common chirality, constant
    memory per module, and visibility and communication restricted to immediate neighbors.
    Unlike prior work, which relaxes the original sliding square move-set, our approach
    uses the unmodified move-set, addressing the additional challenge of handling
    locked configurations. Our algorithm is sequential in nature and operates with
    a worst-case time complexity of O(n^2) rounds, which is optimal for sequential
    algorithms. To improve runtime, we introduce two parallel variants of the algorithm.
    Both rely on a spanning tree data structure, allowing modules to make decisions
    based on local connectivity. Our experimental results show a significant speedup
    for the first variant, and a linear average runtime for the second variant, which
    is worst-case optimal for parallel algorithms.'
author:
- first_name: Irina
  full_name: Kostitsyna, Irina
  last_name: Kostitsyna
- first_name: David Jan
  full_name: Liedtke, David Jan
  id: '55557'
  last_name: Liedtke
- first_name: Christian
  full_name: Scheideler, Christian
  id: '20792'
  last_name: Scheideler
citation:
  ama: 'Kostitsyna I, Liedtke DJ, Scheideler C. Invited Paper: Distributed Rhombus
    Formation of Sliding Squares. In: Bonomi S, Mandal PS, Robinson P, Sharma G, Tixeuil
    S, eds. <i>Stabilization, Safety, and Security of Distributed Systems</i>. Springer
    Nature Switzerland; 2025:325-342. doi:<a href="https://doi.org/10.1007/978-3-032-11127-2_26">10.1007/978-3-032-11127-2_26</a>'
  apa: 'Kostitsyna, I., Liedtke, D. J., &#38; Scheideler, C. (2025). Invited Paper:
    Distributed Rhombus Formation of Sliding Squares. In S. Bonomi, P. S. Mandal,
    P. Robinson, G. Sharma, &#38; S. Tixeuil (Eds.), <i>Stabilization, Safety, and
    Security of Distributed Systems</i> (pp. 325–342). Springer Nature Switzerland.
    <a href="https://doi.org/10.1007/978-3-032-11127-2_26">https://doi.org/10.1007/978-3-032-11127-2_26</a>'
  bibtex: '@inproceedings{Kostitsyna_Liedtke_Scheideler_2025, place={Cham}, title={Invited
    Paper: Distributed Rhombus Formation of Sliding Squares}, DOI={<a href="https://doi.org/10.1007/978-3-032-11127-2_26">10.1007/978-3-032-11127-2_26</a>},
    booktitle={Stabilization, Safety, and Security of Distributed Systems}, publisher={Springer
    Nature Switzerland}, author={Kostitsyna, Irina and Liedtke, David Jan and Scheideler,
    Christian}, editor={Bonomi, Silvia and Mandal, Partha Sarathi and Robinson, Peter
    and Sharma, Gokarna and Tixeuil, Sebastien}, year={2025}, pages={325–342} }'
  chicago: 'Kostitsyna, Irina, David Jan Liedtke, and Christian Scheideler. “Invited
    Paper: Distributed Rhombus Formation of Sliding Squares.” In <i>Stabilization,
    Safety, and Security of Distributed Systems</i>, edited by Silvia Bonomi, Partha
    Sarathi Mandal, Peter Robinson, Gokarna Sharma, and Sebastien Tixeuil, 325–42.
    Cham: Springer Nature Switzerland, 2025. <a href="https://doi.org/10.1007/978-3-032-11127-2_26">https://doi.org/10.1007/978-3-032-11127-2_26</a>.'
  ieee: 'I. Kostitsyna, D. J. Liedtke, and C. Scheideler, “Invited Paper: Distributed
    Rhombus Formation of Sliding Squares,” in <i>Stabilization, Safety, and Security
    of Distributed Systems</i>, Kathmandu, 2025, pp. 325–342, doi: <a href="https://doi.org/10.1007/978-3-032-11127-2_26">10.1007/978-3-032-11127-2_26</a>.'
  mla: 'Kostitsyna, Irina, et al. “Invited Paper: Distributed Rhombus Formation of Sliding
    Squares.” <i>Stabilization, Safety, and Security of Distributed Systems</i>, edited
    by Silvia Bonomi et al., Springer Nature Switzerland, 2025, pp. 325–42, doi:<a
    href="https://doi.org/10.1007/978-3-032-11127-2_26">10.1007/978-3-032-11127-2_26</a>.'
  short: 'I. Kostitsyna, D.J. Liedtke, C. Scheideler, in: S. Bonomi, P.S. Mandal,
    P. Robinson, G. Sharma, S. Tixeuil (Eds.), Stabilization, Safety, and Security
    of Distributed Systems, Springer Nature Switzerland, Cham, 2025, pp. 325–342.'
conference:
  end_date: 2025-10-11
  location: Kathmandu
  name: 27th International Symposium on Stabilization, Safety, and Security of Distributed
    Systems (SSS)
  start_date: 2025-10-09
date_created: 2025-11-23T21:07:12Z
date_updated: 2026-02-11T08:31:14Z
department:
- _id: '79'
doi: 10.1007/978-3-032-11127-2_26
editor:
- first_name: Silvia
  full_name: Bonomi, Silvia
  last_name: Bonomi
- first_name: Partha Sarathi
  full_name: Mandal, Partha Sarathi
  last_name: Mandal
- first_name: Peter
  full_name: Robinson, Peter
  last_name: Robinson
- first_name: Gokarna
  full_name: Sharma, Gokarna
  last_name: Sharma
- first_name: Sebastien
  full_name: Tixeuil, Sebastien
  last_name: Tixeuil
language:
- iso: eng
page: 325-342
place: Cham
publication: Stabilization, Safety, and Security of Distributed Systems
publication_identifier:
  isbn:
  - '9783032111265'
  - '9783032111272'
  issn:
  - 0302-9743
  - 1611-3349
publication_status: published
publisher: Springer Nature Switzerland
status: public
title: 'Invited Paper: Distributed Rhombus Formation of Sliding Squares'
type: conference
user_id: '15578'
year: '2025'
...
---
_id: '64881'
author:
- first_name: Nada
  full_name: Almalki, Nada
  last_name: Almalki
- first_name: Siddharth
  full_name: Gupta, Siddharth
  last_name: Gupta
- first_name: Othon
  full_name: Michail, Othon
  last_name: Michail
- first_name: Andreas
  full_name: Padalkin, Andreas
  last_name: Padalkin
citation:
  ama: 'Almalki N, Gupta S, Michail O, Padalkin A. Efficient Distributed Algorithms
    for Shape Reduction via Reconfigurable Circuits. In: <i>Lecture Notes in Computer
    Science</i>. Springer Nature Switzerland; 2025. doi:<a href="https://doi.org/10.1007/978-3-032-11127-2_5">10.1007/978-3-032-11127-2_5</a>'
  apa: Almalki, N., Gupta, S., Michail, O., &#38; Padalkin, A. (2025). Efficient Distributed
    Algorithms for Shape Reduction via Reconfigurable Circuits. In <i>Lecture Notes
    in Computer Science</i>. Springer Nature Switzerland. <a href="https://doi.org/10.1007/978-3-032-11127-2_5">https://doi.org/10.1007/978-3-032-11127-2_5</a>
  bibtex: '@inbook{Almalki_Gupta_Michail_Padalkin_2025, place={Cham}, title={Efficient
    Distributed Algorithms for Shape Reduction via Reconfigurable Circuits}, DOI={<a
    href="https://doi.org/10.1007/978-3-032-11127-2_5">10.1007/978-3-032-11127-2_5</a>},
    booktitle={Lecture Notes in Computer Science}, publisher={Springer Nature Switzerland},
    author={Almalki, Nada and Gupta, Siddharth and Michail, Othon and Padalkin, Andreas},
    year={2025} }'
  chicago: 'Almalki, Nada, Siddharth Gupta, Othon Michail, and Andreas Padalkin. “Efficient
    Distributed Algorithms for Shape Reduction via Reconfigurable Circuits.” In <i>Lecture
    Notes in Computer Science</i>. Cham: Springer Nature Switzerland, 2025. <a href="https://doi.org/10.1007/978-3-032-11127-2_5">https://doi.org/10.1007/978-3-032-11127-2_5</a>.'
  ieee: 'N. Almalki, S. Gupta, O. Michail, and A. Padalkin, “Efficient Distributed
    Algorithms for Shape Reduction via Reconfigurable Circuits,” in <i>Lecture Notes
    in Computer Science</i>, Cham: Springer Nature Switzerland, 2025.'
  mla: Almalki, Nada, et al. “Efficient Distributed Algorithms for Shape Reduction
    via Reconfigurable Circuits.” <i>Lecture Notes in Computer Science</i>, Springer
    Nature Switzerland, 2025, doi:<a href="https://doi.org/10.1007/978-3-032-11127-2_5">10.1007/978-3-032-11127-2_5</a>.
  short: 'N. Almalki, S. Gupta, O. Michail, A. Padalkin, in: Lecture Notes in Computer
    Science, Springer Nature Switzerland, Cham, 2025.'
date_created: 2026-03-11T07:42:55Z
date_updated: 2026-03-11T07:43:49Z
doi: 10.1007/978-3-032-11127-2_5
language:
- iso: eng
place: Cham
publication: Lecture Notes in Computer Science
publication_identifier:
  isbn:
  - '9783032111265'
  - '9783032111272'
  issn:
  - 0302-9743
  - 1611-3349
publication_status: published
publisher: Springer Nature Switzerland
status: public
title: Efficient Distributed Algorithms for Shape Reduction via Reconfigurable Circuits
type: book_chapter
user_id: '88238'
year: '2025'
...
