Fast on-line determination of quasi-optimal grasp configurations based on off-line analysis and parametrization of the wrist position

Determining the optimum configuration of a mechanical hand in order to grasp an object is a computational hard work, mainly due to the large number of degrees of freedom (fingers and wrist), the existence of a large number of solutions, and the constraints imposed by the object or the task to be don...

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Detalles Bibliográficos
Autores: Färber, Gerrit Hartmut, Suárez Feijóo, Raúl|||0000-0002-3853-7095
Tipo de recurso: informe técnico
Fecha de publicación:2005
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:2117/525
Acceso en línea:https://hdl.handle.net/2117/525
Access Level:acceso abierto
Palabra clave:Robots -- Motion
Grasp configurations
Mechanical hands
Mans mecàniques
Manos mecánicas
Prensió
Prensión
Wrist position
Robòtica -- Informes tècnics
Àrees temàtiques de la UPC::Informàtica::Robòtica
Descripción
Sumario:Determining the optimum configuration of a mechanical hand in order to grasp an object is a computational hard work, mainly due to the large number of degrees of freedom (fingers and wrist), the existence of a large number of solutions, and the constraints imposed by the object or the task to be done. This paper presents an approach to solve this problem under certain conditions, which is then particularized for an anthropomorphic mechanical hand involving 22 degrees of freedom. The configurations of the hand to optimally grasp rectangular parallelepipeds of different sizes with a planar grasp (contact points on the same plane) are determined off-line from the results the wrist position is analyzed and stored as approximated functions of the height and width of the grasped object. This information is used for a fast on-line computation of the hand configuration in a real grasp operation, given the rectangular parallelepiped bounding-box of the part of the object that will be “inside” the hand after the grasp. The approach has been implemented for the mechanical hand MA-I and the paper includes numerical examples.