Singularities of serial robots: identification and distance computation using geometric algebra

The singularities of serial robotic manipulators are those configurations in which the robot loses the ability to move in at least one direction. Hence, their identification is fundamental to enhance the performance of current control and motion planning strategies. While classical approaches entail...

Descripción completa

Detalles Bibliográficos
Autores: Zaplana Agut, Isiah|||0000-0002-0862-3240, Hadfield, Hugo, Lasenby, Joan
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/381329
Acceso en línea:https://hdl.handle.net/2117/381329
https://dx.doi.org/10.3390/math10122068
Access Level:acceso abierto
Palabra clave:Algebras, Linear
Kinematics
Serial robotic manipulators
Singularity identification
Geometric algebra
Rotor group
Distance to a singularity
Àlgebra lineal
Cinemàtica
Àrees temàtiques de la UPC::Informàtica::Robòtica
Descripción
Sumario:The singularities of serial robotic manipulators are those configurations in which the robot loses the ability to move in at least one direction. Hence, their identification is fundamental to enhance the performance of current control and motion planning strategies. While classical approaches entail the computation of the determinant of either a 6×n or n×n matrix for an n-degrees-of-freedom serial robot, this work addresses a novel singularity identification method based on modelling the twists defined by the joint axes of the robot as vectors of the six-dimensional and three-dimensional geometric algebras. In particular, it consists of identifying which configurations cause the exterior product of these twists to vanish. In addition, since rotors represent rotations in geometric algebra, once these singularities have been identified, a distance function is defined in the configuration space C , such that its restriction to the set of singular configurations S allows us to compute the distance of any configuration to a given singularity. This distance function is used to enhance how the singularities are handled in three different scenarios, namely, motion planning, motion control and bilateral teleoperation.