TY - GEN

T1 - Path Accuracy Improvement of Parallel Kinematic Structures by Identification of Friction and Rigid-Body Dynamics

AU - Grotjahn, Martin

AU - Abdellatif, H.

AU - Heimann, Bodo

PY - 2004

Y1 - 2004

N2 - This paper presents a new identification approach for PKM dynamics based on a two-step estimation strategy. A number of local models is identified for different configurations in the first step of the identification scheme. In the second step they are used to obtain the global model of the PKM by application of a least square estimator. The efficiency and capacity of the proposed approach is proved by the experimental application to the linear direct driven hexapod PaLiDA. Excellent identification results and high model quality were found. The implementation of the identified model for feedforward control provides a significant improvement of path accuracy and shows that the consideration of friction is very important. Since only simple PTP-Motion are used for parameter excitation, the approach can be simply implemented in standard industrial controls. The methodology offers the possibility of separate identification of rigid-body and friction dynamics. Additional loads in manufacturing processes can be also quickly identified, in order to guarantee an adaptation to changed model parameters.

AB - This paper presents a new identification approach for PKM dynamics based on a two-step estimation strategy. A number of local models is identified for different configurations in the first step of the identification scheme. In the second step they are used to obtain the global model of the PKM by application of a least square estimator. The efficiency and capacity of the proposed approach is proved by the experimental application to the linear direct driven hexapod PaLiDA. Excellent identification results and high model quality were found. The implementation of the identified model for feedforward control provides a significant improvement of path accuracy and shows that the consideration of friction is very important. Since only simple PTP-Motion are used for parameter excitation, the approach can be simply implemented in standard industrial controls. The methodology offers the possibility of separate identification of rigid-body and friction dynamics. Additional loads in manufacturing processes can be also quickly identified, in order to guarantee an adaptation to changed model parameters.

M3 - Conference contribution

SP - 217

EP - 236

BT - Proc. Of the Parallel Kinematics Seminar, PKS2004

CY - Chemnitz, Deutschland

ER -