*Result*: Disorder and Homeostasis in ANIBOT A Biologically-Inspired Animal Robot.

Title:
Disorder and Homeostasis in ANIBOT A Biologically-Inspired Animal Robot.
Authors:
Castillo K; Department of Mathematics, San Diego State University, 5500 Campanile Drive, San Diego, 92182, CA, USA., Parker M; Department of Mathematics, San Diego State University, 5500 Campanile Drive, San Diego, 92182, CA, USA., Reyes N; Department of Mathematics, San Diego State University, 5500 Campanile Drive, San Diego, 92182, CA, USA., Palacios A; Department of Mathematics, San Diego State University, 5500 Campanile Drive, San Diego, 92182, CA, USA. apalacios@sdsu.edu., McGee EC; Department of Nuclear Engineering, University of California at Berkeley, 110 Sproul Hall #5800, Berkeley, 94720, CA, USA., Longhini P; Nonlinear Dynamics and Materials Research, Naval Information Warfare Center Pacific, Code 71780, 53560 Hull Street, San Diego, 92152, VA, USA., Lopez H; Nonlinear Dynamics and Materials Research, Naval Information Warfare Center Pacific, Code 71780, 53560 Hull Street, San Diego, 92152, VA, USA., Vo K; Nonlinear Dynamics and Materials Research, Naval Information Warfare Center Pacific, Code 71780, 53560 Hull Street, San Diego, 92152, VA, USA.
Source:
Bulletin of mathematical biology [Bull Math Biol] 2026 Feb 21; Vol. 88 (3). Date of Electronic Publication: 2026 Feb 21.
Publication Type:
Journal Article
Language:
English
Journal Info:
Publisher: Springer Country of Publication: United States NLM ID: 0401404 Publication Model: Electronic Cited Medium: Internet ISSN: 1522-9602 (Electronic) Linking ISSN: 00928240 NLM ISO Abbreviation: Bull Math Biol Subsets: MEDLINE
Imprint Name(s):
Publication: New York, NY : Springer
Original Publication: New York, Pergamon Press.
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Grant Information:
N000142412547 Office of Naval Research; N66001-21-D-0041 Naval Information Warfare Center Pacific
Contributed Indexing:
Keywords: Bifurcation; Central Pattern Generator; Coupled nonlinear oscillator; Homeostasis; Network; Symmetry
Entry Date(s):
Date Created: 20260221 Date Completed: 20260221 Latest Revision: 20260309
Update Code:
20260309
DOI:
10.1007/s11538-026-01608-4
PMID:
41721944
Database:
MEDLINE

*Further Information*

*The effects of external perturbations (or disorder) in the Hopf bifurcations of a central pattern generator (CPG) network of neurons that serves as a model for the circuit realization of ANIBOT-a biologically-inspired animal robot with four legs-are studied, analytically and computationally, from the standpoint of homeostasis. In particular, we employ recent developments in the mathematical description of homeostasis, e.g., input-output functions, to explore the CPG response to perturbations of the network connectivity, the internal dynamics of the neurons, and electronic noise as it arises in the circuit realization of ANIBOT. The patterns of locomotion (Walk, Jump, Trot, Bound, Pace, and Pronk) are controlled, mainly, by the phase dynamics of a CPG network. The results show that with the exception of the Walk and Jump gaits, the phase dynamics of all other gaits exhibit perfect homeostatic responses. In addition, a distinctive feature of the network dynamics is that, under certain conditions, the external perturbations can lead to the appearance of certain patterns, which are absent in the unperturbed system, i.e., disorder-induced pattern formation.
(© 2026. The Author(s), under exclusive licence to the Society for Mathematical Biology.)*

*Declarations. Conflicts of Interest: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.*