Abstract
The purpose of this research is to develop a multi-degrees-of-freedom shaking table that can be used for the centrifugal loading test. We use a 6-degrees-of-freedom parallel link shaking table as a mechanism that satisfies the conditions of compact size, high rigidity, multi degrees of freedom. In a parallel link mechanism, since actuators are not mounted perpendicularly in each other, unintended motion often occurs (multi-axis interference problem). When the reference signal is limited to a sinusoidal wave, these interferences cause a periodic error. These periodic errors cause tracking performance deterioration and output exceeding reference signal. It is important for the shaking table to equip a controller that can follow reference motion accurately and safely. However, when a high gain feedback controller is applied to suppress these interference, stability of the control system gets worse. Therefore, in order to solve above periodic error problem, this paper proposes a method to generate the modified reference signal of the acceleration controller based on off-line Inverse Dynamics Compensation via ‘Simulation of feedback control system’(IDCS). Furthermore, this paper shows effectiveness of the proposed method by applying the method to the actual 6-degrees-of-freedom parallel link shaking table. From the experiments it is seen that the periodic error is suppressed and output signal can be accurately followed reference signal.
