JPH0731550B2 - Positioning control device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a positioning device for positioning a member at a target position. More specifically, information is recorded and / or reproduced by using magnetic, optical, or physical means along a concentric or spiral information track provided on the surface of a disk-shaped medium. The present invention relates to a positioning control device such as a magnetic disk device and an optical disk device that enables the positioning.

2. Description of the Related Art In order to record / reproduce information along an information track on a disk surface, a data transducer for reading / writing data is always held on a target information track in accordance with rotation of the disk, that is, track following. Position control must be performed.

Next, the position detecting method on the disk surface of the data transducer for tracking the track will be described. Floppy disk drive (FDD) and hard disk drive (HD
In magnetic disk devices such as D), called the sector servo system, the disk is equally divided into areas called fan-shaped sectors, and identification data called sector servo signals are magnetically recorded on a part of the information track divided for each sector. In some cases, the signal is read for each sector by the data transducer according to the rotation of the disk, and the relative position error with respect to the information track is detected and recognized in a sampling manner to follow the track. Further, in the optical disk device, in the case of the sampling servo system, when the information tracks on the disk surface are provided with track-following pits at regular intervals and are optically detected and used as the identification data in the same manner as above. In the continuous servo system, there is a case in which a spiral or concentric guide groove is provided on the disk surface and the groove is optically detected to follow the track.

Furthermore, the position fluctuation of the information track that occurs during track following is described. In the optical disk device, the information track changes in position (eccentricity) as the disk rotates due to factors such as displacement of the center of rotation when the disk medium is replaced and deviation of the rotation shaft of the spindle motor that rotates the disk. The amplitude of this eccentricity may be from several tens of μm to one hundred and several tens of μm, and the width of the track to be followed (about 1.
6 μm), which is extremely large, hinders the realization of track following. In the FDD of the magnetic disk devices, in addition to the eccentricity similar to that of the optical disk device, another type of eccentricity occurs due to the base film of the disk medium expanding or contracting and being distorted by the influence of heat. The eccentricity of each eccentricity is smaller than that of the optical disk device, and is about several tens to several tens of μm at the most, but this becomes an obstacle in increasing the recording capacity by increasing the track density.

In order to suppress the position variation of the information track due to such eccentricity and realize the track following with sufficient accuracy, the positioning control system has been variously devised conventionally. less than,
One of the conventional positioning control devices will be described with reference to the drawings.

FIG. 17 is a block diagram of a conventional positioning control device.
In the figure, reference numeral 108 denotes an actuator, which allows the data transducer 103 to freely move on the disk 101. The displacement of the selected information track 102 of the disk 101 immediately below the data transducer 103, that is, the amount of eccentricity of the information track, is r, and the displacement of the data transducer 103 is y.
Express with. Reference numeral 104 is a position error detector for detecting a relative position error e = ry between the information track 102 and the data transducer 103, and 106 is at least one of stabilization compensation and deviation compensation of a position control loop including an analog filter. A compensating circuit for performing the above, and a driving circuit 107 for applying a current to the actuator 108. The data transducer 103 is connected to the actuator 108 by a supporting member shown by a dotted line 109. The output signal of the compensation circuit 106 is branched and input to the simulation circuit 113 that simulates the transfer characteristic of the combined system of the drive circuit 107 and the actuator 108.

FIG. 18 is a signal transmission block diagram of a track following servo system of a conventional positioning control device, and mainly shows the flow of servo signals in FIG. This track-following servo system uses the data transducer 1 for the eccentricity r of the information track 102 which is generated as the disk 101 rotates.
Position error signal e to track 03 within a certain error range
= Ry must be operated to be as small as possible. However, the servo signal is the compensation circuit 106, the drive circuit 1
A delay occurs in the process of passing through 07, the actuator 108, the support member 109, and the position error detector 104. Therefore, a certain value of error is maintained between the central position of the data transducer 103 and the central position of the information track 102, and the positioning error remains.

Now, referring to FIG. 17 and FIG. 18, the simulation circuit 113
Outputs the estimated amount ya of the displacement y of the data transducer 103. On the other hand, the position error signal e and the output of the simulation circuit 113 ya
Is input to the adder 110 and outputs ra = e + ya, that is, an estimated amount of displacement (estimated amount of eccentricity) of the information track 102 immediately below the data transducer 103. However, due to the above reason, the displacement y includes a certain delay with respect to the eccentricity amount r, and the estimated amount ya also includes the same delay. Therefore, after obtaining the eccentricity estimation amount ra, this is set for a certain time L
If a virtual eccentricity amount rc whose phase is advanced by just that is obtained and a servo system is configured to cause the data transducer 103 to follow this rc, the displacement y will follow r well. In reality, it is impossible to advance the time, so this is performed as follows using the delay element 111 by utilizing the periodicity of the eccentricity amount. That is, if the estimated eccentricity ra is composed of a high frequency whose fundamental wave is the rotation frequency (1 / T) of the disk, similar to the eccentricity r, this delay element 11
The output rc of 1 is multiplied by rc = ra-e- ^(TL) s = ra-e ^LS . That is, an eccentricity estimation amount with an advanced L time phase compared to ra can be obtained. By obtaining the difference between the eccentricity estimation amount rc and the data transducer displacement estimation amount ya by the adder 112, the position error signal estimation amount without delay ea = rc−
By obtaining ya and adding it to the drive circuit 107 via the compensation circuit 106 to drive the actuator 108, the tracking delay of the data transducer 103 can be eliminated. [Patent Document 1] JP-A-53-106105 [Problems to be solved by the invention] However, the above-mentioned structure has the following problems. First, the transfer characteristics of the combined system of the actuator 108, the data transducer 103, the support member 109, the drive circuit 107, and the like due to tolerance, aging, temperature change, and the like vary. This is a simulated circuit if turned over 11
Unless the circuit constant of 3 is adjusted accordingly, an error is included in the transfer characteristic of the simulation circuit, and an error occurs in the estimated amount ya of displacement of the data transducer. The estimated amount ya further includes an error due to variation in the circuit constant of the simulation circuit 113 and temperature drift. Next, in the case of the track following servo system as shown in the conventional example, the delay element 11 is used instead of directly applying the servo using the position error signal e.
Since 1 is used, there is no effect of suppressing disturbance when it is applied to the actuator 108. Furthermore, in order to shift from the tracking operation for one information track to the tracking operation for another information track, once the loop of the track following servo system is cut off and a track scene is performed, the track following operation is restarted. In the conventional track following servo system configuration in which the element 111 is used, it is not possible to quickly follow a new track due to the action of the servo loop.

In view of the above problems, the present invention provides not only high-accuracy track following performance, but also an error in the estimated amount of displacement of the data transducer can be made sufficiently small, and an effect of suppressing it when disturbance is applied to the actuator Have a
Further, the present invention provides a positioning control device capable of tracking a track even in a transient tracking operation after a track seek.

Means for Solving the Problems In order to solve the above problems, a positioning control device of the present invention is a position error detector for detecting a relative position error between a target member, that is, an information track to be followed by a disk and a moving member, that is, a data transducer. A position detector for detecting the absolute position of the moving member, and a compensation means for performing at least one of stabilization compensation and deviation compensation of the position control loop based on the position error signal output from the position error detector. A first adder for adding the position error signal output by the position error detector and the position signal output by the position detector; a signal based on the output of the compensating means; and the first adder Second addition with the signal based on the output of
And an actuating circuit for applying a current to the actuator means for allowing the moving member to move freely by a signal based on the output of the second adder.

Action The present invention, by adopting the above-described configuration, not only provides highly accurate track following performance, but also can sufficiently reduce the error in the estimated amount of displacement of the data transducer, and when disturbance is applied to the actuator. It is possible to provide a positioning control device that has the effect of suppressing it and that is capable of tracking the track even in the transient tracking operation after the track scene.

First Embodiment A positioning control device according to a first embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a positioning control device according to the first embodiment of the present invention. In the figure, 8 is an actuator,
The data transducers 3 are freely movable on the disk 1. The displacement of the selected information track 2 of the disk 1 immediately below the data transducer 3, that is, the amount of eccentricity of the information track is represented by r, and the displacement of the data transducer 3 is represented by y. 4 is a relative position error e = r between the information track 2 and the data transducer 3.
A position error detector 5 for detecting −y is a position detector for detecting the absolute position of the data transducer 3, and the movable portion of the actuator 8 and the transmission member 10 are mechanically coupled to each other. 6 is a compensation circuit for stabilizing and / or deviation compensating the position control loop consisting of an analog filter, and 11 is an adder for adding the output signal of the position error detector 4 and the output signal of the position detector 5. Bowl, 17
Is an amplifier for amplifying the output signal of the adder 11, 12 is an adder for adding the output signal of the compensation circuit 6 and the output signal of the amplifier 17,
A drive circuit 7 receives the output signal of the adder 12 and applies a current to the actuator 8. The data transducer 3 is connected to the actuator 8 by a supporting member shown by a dotted line 9.

FIG. 2 is a signal transmission block diagram of a track following servo system of the positioning control apparatus in the first embodiment of the present invention, and mainly shows the flow of servo signals in FIG.

The operation of the positioning control device of the present invention configured as described above will be described.

The track-following servo system shown in FIGS. 1 and 2 positions the data transducer 2 within a certain error range so as to follow the fluctuation of the absolute position of the information track 2 caused by the rotation of the disk 1, that is, the eccentricity r. Error signal e = r
-Y must be operated to be as small as possible.

In FIGS. 1 and 2, the position detector 5 outputs an estimated amount ya of the absolute position y of the data transducer 3.
The ya is called an estimator because the position detector 5 does not directly measure the displacement of the data transducer 3, but rather the transmission member.
By estimating the displacement of the data transducer 3 by measuring the displacement of the movable part of the actuator 8 via 10. Next, the position error signal e and the estimated amount ya are added by the adder.
It is input to 11, and ra = e + ya, that is, the estimated amount of displacement (estimated amount of eccentricity) of the information track 2 immediately below the data transducer 3 is output. The signal amplified by the amplifier 17 and the output signal of the compensation circuit 6 are added by the adder 12 and then input to the drive circuit 7 to drive the actuator 8.
The follow-up operation of the data transducer 3 becomes possible.

The operating principle of the positioning control device of the present invention will be described in more detail from another angle.

In FIGS. 1 and 2, the eccentricity estimation amount ra is calculated by the amplifier 17
The remaining servo loop from which the eccentricity estimation loop added to the adder 12 via is removed is a normal track following servo system. In this normal servo system, the gain of the compensating circuit 6 must be infinite in order to make the tracking error e = ry of the data transducer 3 on the information track 2 zero. However, since it is impossible to make the gain infinite in reality, a slight error remains. In the present invention, in addition to the conventional servo loop, by estimating the eccentricity of the information track 2 and directly applying this to the drive circuit 7,
While trying to further reduce the tracking error, it has the following features that are not available in the past. That is, in a relatively low frequency region near the frequency of the eccentricity of the information track 2, assuming that the combined transfer characteristic from the drive circuit 7 to the actuator 8 has a phase delay of almost zero and a gain of about 1, the gain of the amplifier 17 is about 1. By setting y to 1, y = ra
Becomes Therefore, the estimation accuracy of the eccentricity estimation amount ra is extremely high,
When ra = r, y = r, which is e = r-
It is nothing but y = 0. By the way, the compensation circuit 6 at this time
Output becomes zero, but the compensation circuit 6 is
In the figure, it has functions of ensuring loop stability, suppressing disturbance, and eliminating direct current deviation between the central position of the data transducer 3 and the central position of the information track 2.

Next, the signal waveform of each part in the track following servo system of the positioning control device of the present invention will be shown based on a specific example.

FIG. 3 is a block diagram of a concrete track following servo system. S means S of Laplace transform, 15 is an integrator for compensating the deviation of the servo system, 16 is an amplifier for adjusting the loop gain, and 17 is for adjusting the magnitude of the output of the adder 11. It is an amplifier (the gain is ka). (However, ki = 370 and ka = 1 in the figure.) The transfer function of the drive circuit 7 and the actuator 8 shown in FIG. 2 is a second-order lag system as a whole, and the constants p and q have a cutoff frequency of 300 Hz. The value is such that The rotation speed of the disk is 600 rpm, and the displacement r of the information track 2 is given by a sine wave having an amplitude of 20 μm and a frequency of 10 Hz. FIG. 4 (a) shows the signal track displacement r, the data transducer displacement y, the position error detector output e, and the respective signal waveforms when the track following servo system shown in FIG. 3 is simulated on a computer program. ~ (C). In the figure, 0.1 [sec] corresponds to one rotation of the disc.

For comparison, FIG. 5 shows a configuration in which the output of the amplifier 17 is not added to the output of the amplifier 16. In addition, the waveform of each part by the simulation in this case is shown in FIGS.
Shown in.

When the position error signal e is compared between FIG. 4 and FIG.
In the figure, the amplitude is about 3 μm, while in FIG.
It is 0.1 μm, and by adopting the servo system configuration of FIG. 3, there is an excellent effect that the position deviation becomes about 1/30.

A positioning control device according to a second embodiment of the present invention will be described below with reference to the drawings.

FIG. 7 is a block diagram of a positioning control device according to the second embodiment of the present invention. In the figure, the basic configuration is the same as that in FIG. 1, and therefore only the different points will be described below. 13 is an adder
Differentiator for differentiating the output signal of 11, 11 is an adder for adding the output signal of the adder 11 and the output signal of differentiator 13, and 12 is an adder for adding the output signal of the compensation circuit 6 and the output signal of the adder 14. It is a vessel.

FIG. 8 is a signal transmission block diagram of the track following servo system of the positioning control apparatus in the second embodiment of the present invention, and mainly shows the flow of the servo signal in FIG.

The operation of the positioning control device of the present invention configured as described above will be described below.

The track-following servo system shown in FIGS. 7 and 8 is similar to the first embodiment in that the data transducer 2 has a certain error in the fluctuation of the absolute position of the information track 2 caused by one rotation of the disk, that is, the eccentricity r. In order to follow within the range, the position error signal e = ry must be operated as small as possible. However, the servo signal is delayed in the process of passing through the drive circuit 7 and the actuator 8.
That is, in the first embodiment, the drive circuit 7 is operated in a relatively low frequency region near the frequency of the eccentricity of the information track 2.
It is assumed that the combined transmission characteristic from the actuator to the actuator 8 has a phase delay of almost zero and a gain of about one. However, not only in such a case, but also with some phase delay. Further, when the servo system is a discrete time system, a phase delay due to the sample holder is added to this.
Therefore, a certain value of error is maintained between the center position of the data transducer 3 and the center position of the information track 2, and a positioning error remains.

In FIGS. 7 and 8, the position detector 5 outputs the estimated amount ya of the absolute position y of the data transducer 3.
On the other hand, the position error signal e and the estimated amount ya are input to the adder 11,
ra = e + ya, that is, the estimated amount of displacement (estimated amount of eccentricity) immediately below the data transducer 3 of the information track 2 is output. However, for the reason described above, the displacement y includes a delay with respect to the fluctuation (eccentricity amount) r of the position of the information track 2, and the amount ya estimated for this also includes a similar delay. In addition, ya includes an electrical delay when the position detector 5 estimates. Therefore, the eccentricity estimation amount ra also includes the delay caused by these. In order to remove this delay, the eccentricity estimation amount ra is differentiated by a differentiator 13, and the signal amplitude is adjusted by an amplifier or attenuator (not shown), and then added to the original signal ra.
By adding at 14, the eccentricity estimation amount rc with a slightly advanced phase rather than the original eccentricity amount r is obtained. By adding this to the output signal of the compensation circuit 6 by the adder 12 and then inputting it to the drive circuit 7 to drive the actuator 8, it becomes possible to eliminate the tracking delay of the data transducer 3.

Next, the signal waveform of each part in the track following servo system of the positioning control device of the present invention will be shown based on a specific example.

FIG. 9 is a block diagram of a concrete track following servo system. The specific example shown in FIG. 3 was a continuous time servo system, but in this case it is a discrete time servo system. Z means Z of Z transform, and Z ⁻¹ means delay of one sample time. 20 is a sampler, 21 is an integrator for compensating the deviation of the servo system, 22 is a multiplier for adjusting the loop gain, 11 is a differentiator, and 23 is for adjusting the magnitude of the output of the differentiator 11. A multiplier, 24 is a sample holder. (However, ki = 1, kd = 1.) The transfer function of the drive circuit 7 and the actuator 8 shown in FIG. 8 is a second-order lag system, and the constants p and q have a cutoff frequency of 300 Hz. It is such a value. The rotation speed of the disk is 600 rpm, the sampling frequency is 340 Hz, and the displacement r of the information track 2 has an amplitude of 20 μ.
m, frequency shall be given by a sine wave of 10 Hz. The coefficient kd of the multiplier was determined so that the track followability near 10 Hz corresponding to the frequency of eccentricity was optimal. FIG. 10 shows the displacement r of the information track, the displacement y of the data transducer, the output e of the position error detector, and the respective signal waveforms when the track following servo system shown in FIG. 9 is simulated on a computer program.

For comparison, FIG. 11 shows a configuration in which the eccentricity estimation amount rc is not added to the output of the multiplier 22. Figure 12 shows the waveform of each part in the simulation in this case. However,
The position error signal e in FIGS. 10 (a) to (c) and FIGS. 12 (a) to (c) is the signal after passing through the sampler 20.

Comparing the position error signal e between FIG. 10 and FIG.
The amplitude is about 3.5 μm in the figure, while it is about 0.1 μm in FIG. 10, and by adopting the servo system configuration in FIG. 9, the excellent effect that the position deviation becomes about 1/35 is obtained. is there.

Hereinafter, a positioning control device according to a third embodiment of the present invention will be described with reference to the drawings.

FIG. 13 is a block diagram of a positioning control device according to the third embodiment of the present invention. In the figure, the basic structure is the same as that in FIGS. 1 and 7, and therefore only different points will be described below. Reference numeral 18 is a first compensation circuit for performing at least one of stabilization compensation and deviation compensation of a position control loop formed of an analog filter, and 19 is a delay generated in the process of the servo signal passing through the drive circuit 7 and the actuator 8. A second compensation circuit comprising an analog filter for compensation,
Reference numeral 12 is an adder that adds the output signal of the first compensation circuit 18 and the output signal of the second compensation circuit 19.

FIG. 14 is a signal transmission block diagram of the track following servo system of the positioning control device in the third embodiment of the invention, and mainly shows the flow of the servo signal in FIG.

The operation of the positioning control device of the present invention configured as described above will be described below.

The track-following servo system shown in FIGS. 13 and 14 is similar to the first and second embodiments in that the absolute position variation of the information track 2, that is, the eccentricity r caused by the rotation of the disk 1 is changed by the data transducer. The position error signal e = ry must be operated to be as small as possible in order to make 3 follow within a certain error range. However, the servo signal is delayed in the process of passing through the drive circuit 7 and the actuator 8. That is, in the relatively low frequency region near the frequency of the eccentricity of the information track 2, the synthetic transfer characteristic from the drive circuit 7 to the actuator 8 is accompanied by some phase delay. Further, when the servo system is a discrete time system, a phase delay due to the sample holder is added to this. Therefore, an error of a certain value remains between the center position of the data transducer 3 and the center position of the information track 2, and the positioning error remains.

That is, in the same way as described in the second embodiment, the information track 2 is included in the estimated eccentricity ra in FIGS. 13 and 14.
A delay is included with respect to the position variation (eccentricity amount) r of. In order to compensate for this delay, the estimated eccentricity ra is input to a second compensating circuit for compensating the transfer characteristic of the combined system from the drive circuit 7 to the actuator 8 and the output thereof is used rather than the original eccentricity amount. Obtain the eccentricity estimator rc with a little advanced phase,
By adding this to the output signal of the first compensation circuit 18 by the adder 12 and then inputting it to the drive circuit 7 to drive the actuator 8, it becomes possible to eliminate the tracking delay of the data transducer 3.

Next, the track following servo system of the positioning control device of the present invention will be described in more detail based on a specific example.

FIG. 15 is a block diagram of a concrete track following servo system. Similar to the specific example shown in FIG. 9, this case is also a discrete-time servo system. Explaining only the points different from FIG. 9,
In this case, 30 indicates the transfer characteristic of the combined system of the sample holder 24, the drive circuit 7 and the actuator 8, and as shown in the figure, Can be expressed by the general formula However, S is S of the Laplace transform, and k, 1 is a positive integer. Reference numeral 25 is a second compensating circuit configured by a digital filter for compensating the transfer characteristic 30, and as shown in the figure, Can be expressed by the general formula However, Z is Z of Z conversion, and m and n are positive integers. The second compensation circuit 25 includes a sample holder 24, a drive circuit 7 and an actuator 8.
Can be set to compensate for the delay at various frequencies. As a result, it becomes possible to selectively improve the track followability with respect to various types of eccentricity.

FIG. 16 is a characteristic diagram showing the disturbance suppression characteristic of the track following servo system, which shows the position error e with respect to the displacement r of the information track.
The degree of suppression of, ie, e / r is plotted on the vertical axis, and the frequency is plotted on the horizontal axis. The smaller the value on the vertical axis, the greater the degree of suppression. In the figure, 31 indicates the characteristic when the eccentricity estimation amount rc in FIG. 15 is not added to the adder 12, and the suppression rate is generally smaller than the others. Reference numeral 32 shows the characteristic in the case of FIG. 9 of the second embodiment. 33 shows the characteristics in the case of FIG. 15, and the suppression rate is improved at frequencies other than the vicinity of 10 Hz corresponding to the frequency of eccentricity.

As described above, in the positioning control device of the present invention,
The position detector 5 estimates the displacement of the data transducer 3.
Is done indirectly using. Therefore, by sufficiently increasing the mechanical accuracy of the position detector 5, the support member 9, and the transmission member 10, the error in the estimated amount ya of the displacement of the data transducer 3 can be made sufficiently small. Further, as is apparent from the block diagram of the servo system in FIG. 2, even when a disturbance is applied to the actuator 8, the normal servo loop functions of the position error detector 4, the compensation circuit 6, the drive circuit 7, and the actuator 8 are performed. It has the effect of suppressing this. Further, even in the transitional follow-up operation after the track seek, it is possible to quickly follow a new track by the action of the servo loop. The track follow-up control system of the specific configuration example of the first embodiment is a continuous time system, but it may be a discrete time system.

Further, although the track following control system of the concrete configuration examples of the second embodiment and the third embodiment is constituted by the discrete time system, it may be constituted by the continuous time system.

EFFECTS OF THE INVENTION As described above, the positioning control device of the present invention includes a position error detector that detects a relative position error between a target member, that is, an information track to be followed by a disk and a moving member, that is, a data transducer, and a moving member. A position detector for detecting the absolute position of the position error compensation means, and a compensation means for performing at least one of stabilization compensation and deviation compensation of the position control loop based on the position error signal output from the position error detector, A first adder for adding the position error signal output by the error detector and the position signal output by the position detector, a signal based on the output of the compensating means, and an output of the first adder Second, which adds the signal
Tracker with high accuracy by including the adder and the drive circuit for applying a current to the actuator means for freely moving the moving member by the signal based on the output of the second adder. In addition to obtaining tracking performance, the error in the estimated amount of displacement of the data transducer can be made sufficiently small, and it has the effect of suppressing disturbance when disturbance is applied to the actuator. Track follow-up becomes possible even in follow-up operation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a positioning control device according to a first embodiment of the present invention, and FIG. 2 is a track of the positioning control device according to the first embodiment of the present invention shown in FIG. A signal transmission block diagram of the tracking servo system, FIG. 3 is a block diagram of a concrete track following servo system of the positioning control device in the first embodiment of the present invention shown in FIG. 2, and FIG. FIG. 5 is a signal waveform diagram of each part by simulation on the computer in the configuration, FIG. 5 is a block diagram of a normal track following servo system, FIG. 6 is a signal waveform diagram of each part by simulation on the computer in the configuration of FIG. 5, FIG. 7 is a block diagram of a positioning control device according to the second embodiment of the present invention, and FIG. 8 is a signal of a track following servo system of the positioning control device according to the second embodiment of the present invention shown in FIG. 9 is a block diagram of a concrete track following servo system of the positioning control device according to the second embodiment of the present invention shown in FIG. 8, and FIG. 10 is a computer in the configuration of FIG. Fig. 11 is a signal waveform diagram of each part by simulation in Fig. 11, Fig. 11 is a block diagram of a normal track following servo system, Fig. 12 is a signal waveform diagram of each part by computer simulation in the configuration of Fig. 11, Fig. 13 is Block diagram of a positioning control device according to a third embodiment of the present invention,
FIG. 14 is a block diagram of a track following servo system of a positioning control device according to the third embodiment of the present invention shown in FIG.
FIG. 15 is a block diagram of a specific track following servo system of a positioning control device according to the third embodiment of the present invention shown in FIG. 14, and FIG. 16 is a characteristic diagram showing disturbance suppressing characteristics of the track following servo system. FIG. 17 is a block diagram of a positioning control device in the conventional example, and FIG. 18 is a signal transmission block diagram of a track following servo system of the positioning control device in the conventional example shown in FIG. 1 ... Disk, 2 ... Information track, 3 ... Data transducer, 4 ... Position error detector, 5 ... Position detector, 6 ... Compensation circuit, 7 ... Drive circuit, 8 ... Actuator, 9 ...... Support member, 10 ...... Transmission member, 11,12,14
...... Adder, 13 …… Differentiator, 17 …… Amplifier, 18 …… First
Compensation circuit, 19 ... Second compensation circuit.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Hiromi Onodera 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-56-65211 (JP, A) JP-A-1-92813 (JP, A)

Claims (4)

[Claims] 1. A positioning control device for positioning a moving member with respect to a target member, a position error detector for detecting a relative position error between the target positioning position of the target member and the moving member, and an absolute position of the moving member. A position detector for detecting, a compensation means for performing at least one of stabilization compensation and deviation compensation of the position control loop based on the position error signal output from the position error detector, and the position error detector A first adder for adding the output position error signal and the position signal output by the position detector;
A second adder for adding a signal based on the output of the compensating means and a signal based on the output of the first adder, and the moving member by the signal based on the output of the second adder. A positioning control device comprising: a drive circuit that applies a current to an actuator means that allows it to move freely. 2. A positioning control device for positioning a moving member with respect to a target member, a position error detector for detecting a relative position error between the target positioning position of the target member and the moving member, and an absolute position of the moving member. A position detector for detecting, a compensation means for performing at least one of stabilization compensation and deviation compensation of the position control loop based on the position error signal output from the position error detector, and the position error detector A first adder for adding the output position error signal and the position signal output by the position detector; a differentiator for differentiating a signal based on the output of the first adder; and the first addition A second adder for adding a signal based on the output of the differentiator and a signal based on the output of the differentiator,
A third adder that adds a signal based on the output of the compensation means and a signal based on the output of the second adder, and the moving member by the signal based on the output of the third adder. A positioning control device comprising: a drive circuit that applies a current to an actuator means that allows it to move freely. 3. A positioning control device for positioning a moving member with respect to a target member, a position error detector for detecting a relative position error between the target positioning position of the target member and the moving member, and an absolute position of the moving member. A position detector for detecting, a first compensating means for performing at least one of stabilization compensation and deviation compensation of the position control loop based on the position error signal output from the position error detector, and the position error. A first adder for adding the position error signal output by the detector and the position signal output by the position detector, and second compensating means for inputting a signal based on the output of the first adder A second adder for adding a signal based on the output of the first compensating means and a signal based on the output of the second compensating means, and a signal based on the output of the second adder By Positioning control apparatus characterized by being composed of a current and a drive circuit which imparts to the actuator means to enable moving the movable member freely Te. 4. The second compensating means compensates a composite transfer function of a position control loop including at least one of a driving means, an actuator means and a sample and hold means. The positioning control device described.