The New Jersey Institute of Technology's
Electronic Theses & Dissertations Project

Title:	Vibration control on linear robots with digital servocompensator
Author:	Kwadzogah, Roger Kobla
View Online:	njit-etd1999-071 (xi, 61 pages ~ 3.0 MB pdf)
Department:	Department of Electrical and Computer Engineering
Degree:	Master of Science
Program:	Electrical Engineering
Document Type:	Thesis
Advisory Committee:	Chang, Timothy Nam (Committee chair) Meyer, Andrew Ulrich (Committee member) Hou, Edwin (Committee member)
Date:	1999-05
Keywords:	Automatic control --Data processing. Feedback control systems. Control systems --Design.
Availability:	Unrestricted
Abstract:	Control application for active damping of structural vibrations and acoustic noise in mechanical systems is one of the engineering fields that can benefit from advances made in digital signal processors. This thesis project is one such application. It is about a vibration control at the loading point of a high speed linear robotic workcell. A lead zirconate titanate piezoelectric ceramic is used as the actuator and an accelerometer provides the sensing. From experimentally measured frequency response of this system, a shaping filter is designed and added on. The reshaped system is fitted with a third order transfer function design model. And based on this model, a discrete-time control scheme designated “servocompensator” is designed and implemented on a Digital Signal Processing board to control structural vibrations on the robotic workcell. Servocompensator is a control scheme based on the principle of Internal Model Design. The results have demonstrated the servocompensator as a powerful scheme for controlling independently the individual modes within the spectrum of a given vibration signal. In a typical result, as much as 40 dB of attenuation is produced on the targeted mode, where 0 dB is equal to 1 g of acceleration in this application. Furthermore, with the multi-tasking capability of the digital hardware, multiple mode control is demonstrated by multiplexing a number of single-mode servocompensators.