Fractional calculus is a generalization of the integration and differentiation to the fractional (non-integer) order. In this paper, for the first time, we devised a fractionalorder adaptive compensation (FO-AC) method for cogging effect minimization for permanent magnetic synchronous motors (PMSM) position and velocity servo system. Cogging effect is a major disadvantage of PMSM. In our FO-AC ...

In this paper, a study of the fabrication of optical microstructures by fast tool servo (FTS) machining technology is presented. The study started from locating the sources of error exclusively involved in ultra-precision machining with FTS, which are stroke error, spatial error, trajectory generation error and errors of cutting parameters such as spindle speed, depth of cut, feed rate, etc. He...

In this study, a new servo control system is presented for the overhead crane based on discrete-time state feedback approach. It provides both robust tracking and load swing suppression. Inspired from independent joint and computed torque control in robot manipulator field, a new model is derived in which the crane actuators are considered as the main plant. The crane nonlinearities are then tr...

In this paper, based on feedback linearization control method and using a special PI (propotational integrator) regulator (IP) in combination with a feed-forward controller, a three-phase induction servo-drive is speed controlled. First, an observer is employed to estimate the rotor d and q axis flux components. Then, two input-output state variables are introduced to control the dynamics of to...

This paper proposes a new approach to disturbance estimation based on a curvature model to improve the disturbance rejection performance of a servo system. The main feature is that the stability of the control system is guaranteed when the disturbance estimation is incorporated directly into the designed control law. Simulation results show that disturbances are rejected efficiently when this a...

Pneumatic servo actuators are characterized by highly nonlinear dynamics, and as such are well suited to the use of nonlinear control methods requiring measurement of the full state, such as sliding mode control. The requirement of pressure measurement, however, is particularly burdensome, due in large part to the high cost of pressure sensors relative to other components of the servo system. S...

Since extraneous torque is the key factor to affect the accuracy of electro-hydraulic servo loading system, the forming mechanism of extraneous torque was discussed in this work. And then several design methods of loading system controller based on modern control theory were introduced, such as internal model control, Cerebella model articulation control and adaptive backstepping control.

This paper deals with the development of different control techniques such as Fuzzy, Sliding mode, and Sliding Mode fuzzy controllers for the servo drive system. Servomotors are widely used in industry due to their relatively low cost and high reliability. To get high performances we have to control the input variable in uncertainties and disturbance. Two cases are discussed for each control sc...