Publica
Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Optimal Control Simulations of TwoFinger Precision Grasps
 Kecskeméthy, A.: Multibody Dynamics 2019 : Proceedings of the 9th ECCOMAS Thematic Conference on Multibody Dynamics, 1518 July 2019, Duisburg, Germany Cham: Springer International Publishing, 2020 (Computational methods in applied sciences 53) ISBN: 9783030231316 (Print) ISBN: 9783030231323 (Online) S.6067 
 Thematic Conference on Multibody Dynamics <9, 2019, Duisburg> 

 Englisch 
 Konferenzbeitrag 
 Fraunhofer ITWM () Fraunhofer FCC () 
Abstract
Grasping is a complex human activity performed with readiness through a complicated mechanical system as an end effector, i.e. the human hand. Here, we apply a direct transcription method of discrete mechanics and optimal control with constraints (DMOCC) to reproduce humanlevel grasping of an object with a threedimensional model of the hand, actuated through joint control torques. The equations of motions describing the hand dynamics are derived from a discrete variational principle based on a discrete action functional, which gives the time integrator structurepreserving properties. The grasping action is achieved through a series of constraints, which generate a hybrid dynamical system with a given switching sequence and unknown switching times. To determine a favourable trajectory for grasping action, we solve an optimal control problem (ocp) with an objective involving either the contact polygon centroid or the control torques subject to discrete EulerLagrange equations, boundary conditions and path constraints.