On the effect of structural elasticity on the stability and performance of parallel manipulators

This work deals with the control design and control simulation for a parallel structure with reduced degrees of freedom. Firstly, a novel coupled PD-control algorithm which yields uniform eigenfrequencies and properties in all directions of motion is introduced. The results of the linear model are compared to automated MBS-simulations. Afterwards, the stability range is compared to the actual measured stability range which is much smaller. Elasticity effects due to the platform and the joint stiffness are implemented in the MBS-model and evaluated. In the last step, we compare the simulated stability regions of the updated MBS-models to the measured boundaries.