JPS58194175A - Controlling system of positioning conversion head - Google Patents

Abstract

PURPOSE:To attain quickly, the settling of the transient response produced near an objective track by correcting a signal having head driving components in response to an integrating value existing at the end of movement of a conversion head, while inducing the integration in response to the acceleration or deceleration being a difference between a moving position pattern signal calculated on the basis of an objective track signal and a track position signal read actually. CONSTITUTION:When an objective track signal is applied to a feedforward signal generating circuit 1 and a moving position pattern signal generating circuit 2, a feedforward signal obtained from the circuit 1 is supplied to an adder 5, and a difference between a moving position pattern signal obtained from the circuit 2 and a position information signal recorded on a magnetic disc in advance read at a head position detector 7 is applied to the adder 5 via a compensating circuit 6. The magnetic head is moved toward the objective track with an output signal of the adder 5. During that time, an output signal of a subtractor 8, i.e., a difference between the objective position and the actual position, is integrated to form an error signal. This error signal is supplied to the circuit 1 for the correction of the feedforward signal for the next movement, i.e., increase or decrease, allowing to decrease the error.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a transducer head positioning control system that improves as much as possible the problems caused by feedforward control.

(2) Background of the Invention In head positioning control systems used in conventional magnetic disk drives, especially in head positioning control systems in which head position information can only be obtained discretely,
Forward control is adopted. 1. This feedforward control reduces the driving force to move the head to the target position. Based on this value, the actuator is driven to move the head to the target track, but it is inevitable that errors will occur in this control system, so feedback control is also used.

I? , Therefore, conventional feedback control has its limitations, and it is preferable for control. ``Phenomena that do not exist are now appearing, so the development of solutions to them is eagerly awaited.''

(3) Prior art and problems Even if feedback control is used in conjunction with feedforward control as described above, errors caused by internal pressure in the feedforward control system include errors in circuit constants, variations in force coefficients of actuators, etc. In addition to steady errors, there are also relatively large dynamic errors such as resistance value fluctuations due to temperature rise in the actuator winding and drive voltage fluctuations, so each of these errors can be the cause. As a result, errors in the feedforward system increase, making the head movement operation unstable, and as a result, harmful transient responses such as overshoot and undershoot occur in the vicinity of the target track. Therefore, it is unavoidable that a problem will occur in the readout L, -' filling operation of the head.

(4) 1. Purpose of the Invention The present invention was devised by paying attention to the technical problems existing in the conventional system as described above, and its purpose is to automatically reduce errors occurring in the feedforward control system to achieve target tracking. An object of the present invention is to provide a transducer head positioning control method that quickly settles transient responses occurring in the vicinity. 8(5)
0 Structure of the Invention And this purpose is to: 1. respond to a target track signal; 1. In response to the difference between the movement position pattern signal calculated by Kfft and the track position signal taken, and the target trunk signal, 1. In a transducing head positioning control method, a transducing head drive mechanism is operated in response to a head drive component signal generated by a transducing head to position the transducing head on a target track.
This is accomplished by creating an integral in response to the acceleration or deceleration of the difference and modifying the head drive component signal by a value responsive to the integral value present at the end of the transducer head movement.

(6) Embodiments of the Invention The present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of a circuit implementing the present invention. l
is a feedforward signal generation circuit, which is a 2Fi moving position pattern signal generation circuit. A target track signal is sent to these circuits 1 and 2! [3 is not connected.

Further, the circuit 1 is provided with a correction input 4 (the connection of this human power -\ will be described later) which receives a signal 46 for correcting the feedforward signal (head drive component signal) generated therefrom.

5 is an adder, one input of 7 is connected to the output of the feedforward signal generation circuit 1, and the other input is connected to the compensation circuit (
Output 6 (described later) is connected.

The output of the moving position pattern signal generating circuit 2 is connected to the other input of a subtracter 8 which connects the output of a head position detector 7, which will be described later, to one human input. The output of the subtracter 8 is sent to the compensation circuit 6! & continued.

The output of the subtraction 68 is connected to the input of the error integrator 9, whose output is connected to the correction input 4 of the feedforward signal generation circuit l.
connected to.

The error integrator 9 is configured to change the polarity of the C integral during acceleration and deceleration, and the changing manual power is sent to the polarity signal output 11 of the moving position pattern signal generator 2 via the polarity converter 10. It is connected.

The output of the adder 5 is connected to an actuator (head drive mechanism) 13 via a power amplifier 12.

Next, the operation of a circuit implementing the present invention with the above-described configuration will be explained.

In order to position a transducing head such as a magnetic head to one of the recording tracks of a recording medium such as a magnetic disk, a target track signal for this purpose is sent to a feedforward signal generating circuit 1 and a moving position pattern signal generating circuit 2. When supplied, a feedforward signal (head drive component signal) is generated from circuit 1 ((2) in Fig. 2).
-1)), and a moving position pattern signal is generated from the circuit 2 (see (2-2) in Figure 1@2).

The signal from the circuit 1 is supplied to the adder 5, and a difference signal between the output signal of the circuit 2 and the position information *ii signal recorded in advance on the magnetic disk, which is read by the head position detector 7C, is generated. The signal is supplied to the adder 5 through a compensation circuit 6'ft.

The output signal of the adder 5 is supplied to the actuator 13 via the power amplifier 12, and the magnetic head is moved toward the target track. Meanwhile, the output signal of the subtracter 8, that is, the target position and the actual position, are The difference is integrated during the -SS excitation operation up to the above-mentioned target track while switching between the acceleration time period and the deceleration time period according to the output signal of the polarity converter 10. At the end of the movement,
The value generated from the error integrator 9 is shown in Table 1 as the error signal 1 in feedforward control.

This -difference signal is supplied to the feedforward signal generating circuit 1 to modify, ie increase or decrease, the feedforward signal for the next movement. Due to this K, the error in the feedforward signal used for movement is reduced.

Therefore, the moving operation is stabilized, the transient response near the target track is quickly settled, and the time required to start the read/write operation is shortened.

I: It is also possible to digitize the necessary circuits in the circuit of the first embodiment. In that case, it is necessary to provide an analog-to-digital conversion circuit or a digital-to-analog conversion circuit between the analog section and the digital section. Do that 7 and digitize it 4! In addition, the part inside the broken line 14 can also be made up of nicrobrosenona.

(7) According to the present invention, the error in the foot node A1 node signal is automatically reduced, so the moving operation is stable and the transient response near the target track is quick. It is set to . Therefore, effects such as the time Fi until entering the read 2/4 writing operation can be shortened can be obtained.

[Brief explanation of the drawing]

FIG. WA1 is a block diagram of a circuit implementing the present invention, and FIG. 2 is a signal waveform diagram used to explain the circuit of FIG. 1. In the figure, 1 is a feedforward signal generation circuit, 2
is a moving position pattern signal generation circuit, 5 is an adder, 6 is a compensation circuit, 7 is a head position 11 detector, 8 is a subtracter, 9 is an error integrator, 10ki polarity converter, ]2 is a power increaser, 1
3 is an actuator. Applicant: Hiroshi Matsuoka, Patent Attorney, Fujitsu Limited

Claims (1)

[Claims] a difference between a moving position pattern signal calculated in response to the target track signal and an actually read track position signal;
In the conversion head positioning control method, the conversion head drive mechanism is operated in response to the head drive component signal generated in response to the target track signal to position the conversion head on the target track. A transducer head positioning control method comprising: generating a corresponding nine integrals, and modifying the head drive component signal by a value corresponding to the integral value existing at the end of movement of the transducer head. .