Dynamic manipulation of a string using a manipulator-parameter identification and control based on a rigid body link model

Manipulation of deformable objects is an important subject for housekeeping and care robots. Dynamic manipulation of a string is studied in this paper as an example of deformable objects. The string is modeled by a rigid body link with passive joints in two-dimensional space. The parameters of the joint stiffness and viscosity of the string model are identified experimentally using a high-speed video camera. The desired trajectory of the manipulator is searched by using the optimal control method. The manipulator is controlled with the desired trajectory to manipulate the string. In this paper many experiments of flinging-up motion are conducted using two-link and three-link models of the string. The experimental results show the validity of the proposed method.