Application of machine learning for isomorphic analysis of robotic wrist mechanisms

Application of machine learning for isomorphic analysis of robotic wrist mechanisms

Jiyaul MUSTAFA, Abdullah Aamir HAYAT

Abstract. Robotic wrist mechanisms are essential for achieving dexterity, precision, and orientation control in manipulators. Traditional isomorphic analysis, based on graph-theoretic tools such as connectivity matrices, articulation points, and Wiener numbers, is effective but limited by scalability, efficiency, and the need for manual interpretation. This paper proposes a machine learning (ML) framework that represents wrist topologies as graphs and applies Graph Neural Networks (GNNs) to identify structural equivalence. A benchmark dataset was created from Tsai’s atlas of spherical and non-spherical wrist mechanisms, augmented with synthetically generated topologies. The preliminary simulation results demonstrate that the GNN-based model achieves over 95% accuracy in classifying isomorphic and non-isomorphic designs, while reducing classification time by approximately 60% compared to the Wiener number method. This preliminary study relies heavily on a data set, which may misclassify symmetrical structures. With this, the future work aims to expand the data sets, conduct detailed computational comparisons, and utilise other learning approaches.

Keywords
Robotic Wrist Mechanisms, Isomorphism, Graph Theory, Machine Learning, Graph Neural Networks, Mechanism Synthesis, Structural Analysis

Published online 6/20/2026, 10 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Jiyaul MUSTAFA, Abdullah Aamir HAYAT, Application of machine learning for isomorphic analysis of robotic wrist mechanisms, Materials Research Proceedings, Vol. 67, pp 465-474, 2026

DOI: https://doi.org/10.21741/9781644904176-62

The article was published as article 62 of the book Climate Action and Sustainability

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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