In terms of the state space model of actuator in hard disk drive, this paper presents digital servo controllers (seeking mode and settling mode) using pole placement technique and optimal control technique to meet requirements of head position system such as average seek time, position accuracy.
Also it introduces the servo control system composed of servo controllers, S7-300 PLC and ProTool which is designed on the basis of Profibus-DP fieldbus. Such system features simple structure, convenient control and easy maintenance, etc. In addition, the software design and the communication process between servo controllers and PLC on this system are introduced.
This technique, based on side locking to an atomic transition using a servo controller, is very simple and can be implemented straightforwardly to lock the laser at the red detuned frequency position required for laser cooling experiments.
Tuning of a digital disk drive servo controller using fixed-structure H∞ controller optimization
To address the problem of improving the positioning accuracy of the read write head of hard disk drives (HDDs), we present a tuning methodology for the HDD servo controller based on the fixed-structure H∞ controller optimization.
In this paper, the development of a disturbance observer that supplements the nominal head servo controller in minimizing the effects of the tape transients is presented.
Finally, test results are presented to illustrate the effectiveness of the servo controller.
With this solution, in fact, the characteristics of the system to be controlled by the servo-controller are rather independent from all possible variations of electrical impedance of the VCM and power supply voltage.
This gives the tracker the properties of a servo-controller with position feedback.
Development of a servo-controller of heart rate using a cycle ergometer
Thus, we developed a servo-controller of HR using a cycle ergometer.
We then examined the performance of the servo-controller of HR in 55 healthy volunteers.
The machine-tools performances within the framework of high-speed machining both depend on the design of the reference trajectory and on the tuning of the servo controllers.
(1) Conditions of controllability and observability for enlarged system, (2) a design method of optimal preview servo controllers, and (3) a simple and convenient algorithm of control law are obtained.
In order to suppress the stationary error between a reference trajectory and a servo system response, servo controllers often include the integral characteristic.
The uncertainty model can be used for analysis and synthesis of robust servo controllers.
There are large contouring errors around sharp corners when low-bandwidth servo controllers (such as P-PI control) are used.