of Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy VISUAL SERVO TRACKING CONTROL VIA A LYAPUNOV-BASED APPROACH By Guoqiang Hu December 2007 Chair: Dr. Warren E. Dixon Major: Mechanical Engineering Recent advances in image processing, computational technology and control theory are enabli...

This paper presents on-line tool breakage detection of small diameter drills by monitoring the AC servo motor current. The continuous wavelet transform was used to decompose the spindle AC servo motor current signal and the discrete wavelet transform was used to decompose the feed AC servo motor current signal in time–frequency domain. The tool breakage features were extracted from the decompos...

Servo systems, consisting of actuators, drive trains and loads, are commonly used throughout both the robotic and machine tool industries. One important servo problem is the precise position and velocity control of each joint used in a robotic manipulator. Olle of the factors governing performance of such systems is the mism.atch that often exists between motor and load inertias. This paper dis...

This paper discusses the design and implementation of two track-following controllers for dual-stage hard disk drive servo systems. The first controller is designed by combining an outer loop sensitivity-decoupling (SD) controller with an inner loop disturbance observer (DOB). The second is designed by combining mixed H2/H∞ synthesis techniques with an add-on integral action. The designed contr...

This paper discusses the possibility to use low-cost on/off valves instead of servo valves even in demanding servo applications. Different on/off control techniques are first reviewed and analyzed. Then the basic principles of suggested Digital Hydraulics technology are introduced and some tracking control results are presented. Results show that energy efficient and high-quality position and v...

In this paper, an intelligent robust position controller for permanent-magnet synchronous motor (PMSM) servo drives is proposed. The intelligent robust position controller consists of a two-degrees-offreedom integral plus proportional & rate feedback (2DOF I-PD) controller in addition to an on-line trained neural-network model-following controller (NNMFC). This controller, 2DOF I-PD NNMFC, comb...

This paper deals with the problem of the shaft speed estimation in a digitally controlled DC servo drive. Some different observer structures are presented and compared. The developed extended observers enable proper estimation of the plant state variables, even under the action of a constant or slow varying load torque disturbance. Two useful procedures for the adjustment of observer gains are ...

In order to find and treat fault or abnormal occurrences in numerically controlled machine tool of flexible manufacturing system in real-time, a study for computer numerically controlled (CNC) on-line fault diagnostics system has been carried out. The system can look up one or more sticking points of numerically controlled machine tool fault simply, locate CNC faults rapidly and accurately, but...