Modeling and disturbance compensation aided by multibody dynamics analysis in shaking table systems

Abstract

This paper presents an approach for modeling and disturbance compensation in multi-axis shaking table systems. Shaking table system is one of the facilities for seismic tests, where the accurate reproducibility of earthquake acceleration waveforms is essentially desired to evaluate the precise vibratory responses of specimen. However, the rotational motion due to overturning moment of specimen generates as a disturbance for the actuator control system, resulting in the lower reproducibility for the desired earthquake acceleration by deterioration of table motion performance. In order to compensate for the disturbance, at first, the simulator of shaking table including the specimen and control system is modeled using a multibody dynamics analysis including in a control CAD software. Based on the simulator, compensation signals that can cancel the disturbance are generated by an iterative learning control on the simulation, where the compensation signals are stored as time-series data. By using the compensation signals in the actual experiments, effects of the disturbance can be suppressed by the compensation signals in a feedforward control manner without repetitive actual excitations. The effectiveness of proposed control approach has been verified by experiments using a laboratory prototype.

Human-induced force reconstruction using a non-linear electrodynamic shaker applying an iterative neural network algorithm

“…Another classical alternative consists of using an iterative learning control system (ILC) [16,17]. The application of this control method to shaking tables has been explored in [18,19,20].…”

Iterative learning control-based ripple compensation in web handling systems

“…It is difficult for the disturbance observer to estimate disturbance with high accuracy and without delay because the bandwidth that can be compensated is limited from the viewpoint of ensuring stability. Therefore, this paper presents a design approach of tension and velocity control systems based on an iterative learning control (ILC) (Bristow et al, 2006;Seki and Iwasaki, 2015;Oomen, 2020a) in consideration of periodic ripple disturbance suppression in the web handling system. Web handling systems are often used under constant tension and constant transportation velocity.…”

Simulador sísmico de bajo coste para uso en prácticas de docencia

“…Para cargas mas pesadas Kaida et al [4], presentan una mesa que se mueve con actuadores hidráulicos, y que que ocupa un espacio menor que las opciones comerciales, debido a la disposición que toman los actuadores respecto de la mesa. Todo esta controlado desde la herramienta (MATLAB/Simulink by Math-Works, Inc.) [5] Este trabajo presenta el diseño y el cálculo previo del simulador de bajo coste, desarrollado por el grupo de Automática, Robótica y Mecatrónica de la Universidad de Almería. El apartado 2 describe los análisis previos realizados, la cadena cinemática elegida, y las ecuaciones cinemáticas y dinámicas que se han elegido para el cálculo de los movimientos del sistema mecatrónico.…”