Modares Mechanical Engineering

Modares Mechanical Engineering

An Extension to "Robust cooperative multiple flexible-joint arms control using the q-Bernstein-Schurer operators as the uncertainty approximator: A singular perturbation approach"

Document Type : Original Article

Authors
karim bayat 1
alireza izadbakhsh 2
ali jamali 3
amir hooshang mazinan 1
1 Department of Electrical Engineering Control , ST.C., Islamic Azad University, Tehran, Iran
2 Department of Electrical Engineering , Ga. C., Islamic Azad University, Garmsar, Iran
3 Department of biomedical engineering , Sha. C., Islamic Azad University, Shahrood, Iran
10.48311/mme.2026.117226.82872
Abstract
Abstract: This paper introduces a robust adaptive controller tailored for collaborative multiple robots and equipped with elastic joints. It utilizes a simple model of manipulator dynamics, treating all other dynamics as lumped uncertainty. The proposed approach integrates Function Approximation Techniques (FAT), specifically Bernstein-type rational functions, to estimate lumped uncertainty. Recent advancements have utilized FAT-based robust adaptive controllers for uncertainty estimation. However, our innovation distinguishes itself from prior research by minimizing the required regressor matrices. This advantage becomes particularly pronounced as the number of manipulators and their degrees of freedom increase. In addition, the coefficients of the Bernstein-type rational functions are adjusted by the adaptation laws derived from stability analysis, which are not presented in the previous literature. To the best of our knowledge, this paper marks the first engineering application of Bernstein-type rational functions for function approximation in adaptive form. Stability analysis guarantees that all error signals remain uniformly ultimately bounded (UUB). The theoretical advancements are validated by employing two elastic joint manipulators to transport a rigid object. The outcomes are also compared with two advanced approximation techniques to show the precision and effectiveness of the proposed controller design. The results exhibit the usefulness of the proposed control scheme, facing uncertainties and disturbances
Keywords
Bernstein-type rational functions
Collaborative robots
Elastic joints
Function approximation technique
Subjects
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Modares Mechanical Engineering
Volume 26, Issue 8
August 2026
Pages 649-663