Authors:
Adrián Peidró
;
Óscar Reinoso
;
Arturo Gil
;
José María Marín
;
Luis Payá
and
Yerai Berenguer
Affiliation:
Miguel Hernández University, Spain
Keyword(s):
Closed-chain Mechanism, Isolated Singularity, Taylor Expansion, Stability.
Related
Ontology
Subjects/Areas/Topics:
Engineering Applications
;
Informatics in Control, Automation and Robotics
;
Intelligent Control Systems and Optimization
;
Mechatronics Systems
;
Robot Design, Development and Control
;
Robotics and Automation
;
Signal Processing, Sensors, Systems Modeling and Control
Abstract:
When the geometric design of a closed-chain mechanism is non-generic, the singularity locus of the mechanism
may exhibit isolated points. It is well known that these isolated points are unstable since they disappear
or generate/reveal cusps when the geometric design of the mechanism slightly deviates from a non-generic
design, possibly affecting the ability of the mechanism to reconfigure without crossing undesirable singularities.
This paper presents a method based on second-order Taylor expansions to determine how these isolated
singularities transform when perturbing the different geometric parameters of a non-generic mechanism. The
method consists in approximating the singularity locus by a conic section near the isolated singularity, and
classifying the resulting conic in terms of the perturbations of the different geometric parameters. Two non-generic
closed-chain mechanisms are used to illustrate the presented method: an orthogonal 3R serial arm
with specified positio
n for its tip, and the planar Stewart parallel platform.
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