Sensor-Based Identification of Singularities in Parallel Manipulators

[EN] Singularities are configurations where the number of degrees of freedom of a robot changes instantaneously. In parallel manipulators, a singularity could reduce the mobility of the end-effector or produce uncontrolled motions of the mobile platform. Thus, a singularity is a critical problem for...

ver descrição completa

Detalhes bibliográficos
Autores: Pulloquinga-Zapata, José Luis, Ceccarelli, Marco, Mata Amela, Vicente|||0000-0003-2255-0567, Valera Fernández, Ángel|||0000-0001-6843-6394
Formato: artículo
Fecha de publicación:2024
País:España
Recursos:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/220290
Acesso em linha:https://riunet.upv.es/handle/10251/220290
Access Level:acceso abierto
Palavra-chave:Robotics
Parallel manipulators
Kinematics
Singularities
Experimental analysis
Descrição
Resumo:[EN] Singularities are configurations where the number of degrees of freedom of a robot changes instantaneously. In parallel manipulators, a singularity could reduce the mobility of the end-effector or produce uncontrolled motions of the mobile platform. Thus, a singularity is a critical problem for mechanical design and model-based control. This paper presents a general sensor-based method to identify singularities in the workspace of parallel manipulators with low computational cost. The proposed experimental method identifies a singularity by measuring sudden changes in the end-effector movements and huge increments in the forces applied by the actuators. This paper uses an inertial measurement unit and a 3D tracking system for measuring the end-effector movements, and current sensors for the forces exerted by the actuators. The proposed sensor-based identification of singularities is adjusted and implemented in three different robots to validate its effectiveness and feasibility for identifying singularities. The case studies are two prototypes for educational purposes-a five-bar mechanism and an L-CaPaMan parallel robot-and a four-degree-of-freedom robot for rehabilitation purposes. The tests showcase its potential as a practical solution for singularity identification in educational and industrial robots.