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...

Different methods for change detection of signal features are compared for a residual generated at a hydraulic servo axis. The residual is based on a physical model of the pressure buildup inside the hydraulic cylinder. Nevertheless, it is augmented with an observer to counteract slight model impurities even over prolonged periods of operation. Different sensor faults are introduced, which affe...

In this study, the control performance of a hydraulic servo system with a feedback linearization compensator is investigated. The focus of this study is set on the quantitative investigation of the effects(sensitivities) of disturbances and system parameters’ variation on control performances of the hydraulic control system. Finally, verifies the efficacy of a disturbance observer to overcome t...

Micro-optical devices, e.g., micro lenses, micro mirrors, play an important role in high speed data, voice and video signal transmissions. In this study, a new method of fabricating micro optical devices was investigated. The method is different from traditional fabrication processes in the sense that that the micro optical elements were simultaneously machined in a process known as slow tool s...

This paper will address two issues associated with the implementation of a hydraulically powered dissimilar muster-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented. (Schill...

This project aims to develop a novel large stroke asymmetric pneumatic servo system of a hardware-in-the-loop for path tracking control under variable loads based on the MATLAB Simulink real-time system. High pressure compressed air provided by the air compressor is utilized for the pneumatic proportional servo valve to drive the large stroke asymmetric rod-less pneumatic actuator. Due to the p...

Modern computer-aided design and dynamics simulation tools allow design and testing to be performed in a virtual-reality environment. The integration of controller synthesis programs also makes it possible to perform servo tuning without actually having to build a prototype. However, most servo controllers are based on integer processors for machine tools, and the integer numbers entering into ...

A directional drilling tool control unit whose design is based on servo control of a rotary valve using the roll-stabilised instrumented system approach has been successfully used in oil fields for over twenty years. In this paper, Field Oriented Control (FOC) is applied to cascaded voltage regulation and servo control using a open-loop plant model of the roll-stabilised control unit. The servo...

The hard disk drive storage industry is driven to increase data storage density, with increasing tracks per inch (TPI) and bits per inch (BPI) on the recording media. In the development of higher density recording, high-speed testing of magnetic heads and media in engineering and manufacturing environments has traditionally focused on spinstands and disk head testers. This paper describes a hig...