Session: SE-07-01 Seismic Evaluation of Systems, Structures and Components

Paper Number: 123964

123964 - Low Computational Cost Online Acceleration Compensation Method for High-Frequency Vibration and Experimental Verification on a 6-Degree-of-Freedom Shaking Table 

Vibration experiments using shaking tables are being conducted to evaluate the seismic resistance of buildings and the ground. Acceleration amplitude is an important parameter in vibration experiments and must be controlled accurately. Target value compensation and model-based control based on the input/output characteristics obtained from preliminary  excitation experiments are generally performed. However, preliminary excitation experiments cannot be performed in experiments to observe irreversible responses such as damage to the specimen due to excitation. Therefore, a control method that does not require trial excitation or that can obtain control parameters during excitation is required. In this study, we propose a method that measures the amplitude of each wave in excitation targeting a sine wave, and corrects the input online using the measured amplitude. In the proposed method, the shaking table is regarded as a discrete-time plant with one input and one output, with the command displacement amplitude of one sine wave as the input and the measured acceleration amplitude as the output. This method was tested on an actual Stewart platform type hydraulic shaking table. Compensation calculations are performed for each wave rather than for each calculation cycle of the controller, so the amount of calculation is less compared to methods that implement continuous time domain controllers, and it can be implemented using inexpensive calculation equipment. The experiment started with no model, and the correction calculation converged in about 8 waves in the frequency band from 1 Hz to 10 Hz. The acceleration amplitude control error was less than 5%.

Presenting Author: Ryo Hosoda Solutions inc.

Presenting Author Biography: Ryo Hosoda is a manager in the measurement control division of Solutions Inc.
He works on the development of control hardware and software for hydraulic testing machines.
He is also a doctoral student at Tokyo University of Agriculture and Technology.

Authors:

Ryo Hosoda Solutions inc.
Yasutaka Tagawa Tokyo University of Agriculture and Technology