Soleymani M, Hamidizadeh M, Sayahi S, Moradzadeh H, Rahmani M. Fuzzy control of a seismic shake table using a vision-based displacement measurement system. Modares Mechanical Engineering 2015; 14 (14) :117-124
URL:
http://mme.modares.ac.ir/article-15-8181-en.html
1- Mechanical Engineering Department, Faculty of Engineering, Arak University
Abstract: (5655 Views)
Control of seismic shake table in order to track the predefined earthquake profile is a key concern in design of seismic shake tables. This paper proposes a vision-based real time displacement measurement system using image processing techniques to control a laboratory-scale seismic shake table. The shake table is controlled via a fuzzy-supervisory controller, an inner PID loop and a Fuzzy outer one, whose feedback is provided by the vision-based measurement system. To minimize tracking errors, the fuzzy controller uses displacement and acceleration responses as its feedbacks. For this purpose, a camera and an image processing application are utilized to measure the motions directly in real time. Results are sent to a host PC through a network as the controller feedback. Proposed system performance is compared with an alternative system which utilizes a linear encoder as displacement sensor and controller feedback. Test results prove effectiveness of the proposed fuzzy system in cutting back the tracking errors. In addition, the vision-based system uses a very low cost camera to measure the displacement directly. It has appropriate accuracy, works in real time, and doesn't need any contact with the table, comparing to the encoder version.
Article Type:
Research Article |
Subject:
Control Received: 2014/07/25 | Accepted: 2014/08/16 | Published: 2014/10/11