JPH10275433A - Disk recording/reproducing device and head positioning control system applied to it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a servo system excellent for a vibration-proof characteristic without increasing a servo band and requiring a vibration removal mechanism by a function executing effective disturbance compensation at a head positioning control time for the disturbance such as vibration and an impact, etc. SOLUTION: In the servo system applied to an HDD, a disturbance compensation part 3 using an acceleration sensor 5 provided on e.g. a head slider of a head actuator mechanism is provided. A compensation controller 4 in the disturbance compensation part 3 estimates the disturbance based on an acceleration detection value G by the acceleration sensor 5 and a control amount Sa from the servo controller 1, and generates a disturbance compensation value C for cancelling the disturbance from the control amount Sa.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk recording / reproducing apparatus which uses a disk as a recording medium and controls the positioning of a head at a target position on the disk to record / reproduce data. And a disk recording / reproducing apparatus applied to an optical disk apparatus.

[0002]

2. Description of the Related Art Conventionally, a hard disk drive (HD)
In D), servo information is recorded in advance on a disk used as a recording medium, and a head for positioning the head at a target position (target track) on the disk using the servo information reproduced by the head. A positioning control system (servo system) is provided.

In particular, a small HDD employs a servo system of a sector servo system in which servo sectors for servo information arranged on each track are provided together with data sectors (user data areas) on a disk.

Here, the servo information includes track address (cylinder address) information for identifying a track on a disk on which a head is located, and servo burst information for detecting a head position within the range of one track. Are roughly divided into The servo system obtains the track address information and the servo burst information from the servo information sampled at a sampling period determined by the number of servo sectors and the number of rotations of the disk. The servo system performs seek control of the head using the track address information (speed control to the target track) and track following control using the servo burst information (position control within the range of the target track). In the track following control, the servo system uses the servo burst information to calculate a position error with respect to a target position (within the range of the target track) of the head, and calculates a control amount for eliminating the position error. Execute control.

By the way, small HDDs are often mounted inside personal computers. For this reason, if vibration or shock is applied to the computer from outside, the HD
D also has the effect of vibration and impact. In addition, a small HDD mounted on a recent portable personal computer
Is often used especially in an environment where vibration or impact is applied.

[0006]

As described above, a small HDD mounted on a personal computer has a high possibility of being subjected to external vibration or shock. Therefore, it relates to disturbance compensation for suppressing the influence of so-called disturbance. Technology is important. In particular, in the HDD, it is necessary to control the positioning of the head at the target position with high precision, so that when the influence of disturbance is great, the track following control becomes difficult. Traditionally,
Methods have been proposed in which the servo band is increased as much as possible to improve the vibration proof characteristics, or a vibration isolation mechanism is attached to the HDD device body.

However, in the sector servo system, the format efficiency of the disk (increase in the number of data sectors)
From the viewpoint, it is difficult to increase the sampling frequency by increasing the number of servo sectors. Generally, in a sample value control system, there is a phase delay due to a sample hold. In order to prevent this phase delay from affecting the control system, it is necessary to limit the servo band to about 1/7 or less of the sampling frequency. It is said that there is. Therefore, there is a limit to improving the anti-vibration characteristic in the head positioning control by increasing the servo band described above. In addition, in order to attach the vibration isolation mechanism to the HDD device main body, a structural device is required, and it is particularly difficult for a small HDD to be mounted on a portable personal computer.

An object of the present invention is to provide a function for executing effective disturbance compensation at the time of head positioning control for disturbances such as vibrations and shocks, without increasing the servo band or requiring a vibration isolation mechanism. Another object of the present invention is to realize a servo system having excellent vibration resistance.

[0009]

SUMMARY OF THE INVENTION The present invention relates to an HDD, for example.
In a disk recording / reproducing apparatus, a sensor means provided on a head slider, for example, of a head actuator mechanism, and a servo means for calculating a control amount of the head actuator mechanism based on positional error information of the head with respect to a target position during head positioning control A servo system having disturbance compensating means for estimating a disturbance based on a detection value of the sensor means and a control amount calculated by the servo means and eliminating the disturbance.

The sensor means is an acceleration sensor for detecting an acceleration (angular acceleration) generated in a predetermined direction of the head actuator mechanism, and detects an acceleration value including a disturbance. The disturbance compensating unit estimates the amount of disturbance from an error between the acceleration value from the sensor unit and the control amount calculated by the servo unit (that is, the acceleration value for moving the head), and controls the servo unit. Compensation processing is performed to eliminate the disturbance value estimated from the quantity.

With such a configuration, when a disturbance acts during the follow-up control for causing the head to follow the target position on the disk, the servo system estimates the value of the disturbance included in the control amount for the follow-up control. By eliminating the disturbance from the control amount, disturbance compensation for the following control is executed. Therefore, as a result, a reduction in positioning accuracy or unstable positioning control due to the effect of disturbance can be suppressed, and a reliable data recording / reproducing operation can be realized.

According to another aspect of the present invention, there is provided a servo system having means for arranging acceleration sensors at two positions of a head actuator and detecting angular acceleration during rotation operation of the head actuator based on detection values of the respective acceleration sensors. is there. The disturbance compensating means estimates a value of the disturbance from an error between the angular acceleration of the head actuator and the control amount of the servo means, and performs a compensation process for eliminating the disturbance from the control amount.

With such a configuration, it is possible to suppress the influence on the estimated value of disturbance due to the acceleration component when the entire HDD moves. In other words, the detection value of one acceleration sensor includes an acceleration component when the entire HDD moves, which affects the estimated value of disturbance. On the other hand, according to the present method, it is possible to accurately calculate the angular acceleration during the rotation operation of the head actuator by calculating the angular acceleration using the detection value of each acceleration sensor.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a block diagram showing a configuration of a servo control system related to the first embodiment. FIG. 2 is a block diagram showing a main part of an HDD related to the first embodiment. FIG. 3 is a block diagram showing a configuration of a disturbance compensation controller related to the embodiment, FIG. 4 is a diagram showing a structure of an acceleration sensor related to the embodiment, and FIG. 5 is related to the embodiment. FIG. 6 is a diagram showing a mounting position of the acceleration sensor, and FIG. 6 is a flowchart for explaining an operation of the servo system of the embodiment. (Structure of Servo System) The servo system of this embodiment comprises a control system as shown in FIG.
It is assumed that the present invention is applied to a head positioning control system D (see FIG. 2). The servo system roughly includes a servo controller 1, a head driving mechanism 2, and a disturbance compensating unit 3 related to the present embodiment. The servo controller 1 is a main component, and inputs a position error E between a target position D and a current position P of the head, and outputs a head driving mechanism 2
Is a feedback controller that outputs a control amount Sa for controlling the driving of.

The head drive mechanism 2 includes a head actuator for moving the head to a target position (a target track on the disk) and a voice coil motor (VC).
M). The disturbance compensator 3 has a compensation controller 4 and an acceleration sensor 5. The compensation controller 4 receives the detection value G from the acceleration sensor 5 and the control amount Sa from the servo controller 1, estimates the value of the disturbance (acceleration value) applied to the system, and compensates for eliminating the disturbance. Output value C. (Configuration of HDD) Next, a configuration of an HDD to which the servo system of the present embodiment is applied will be described with reference to FIG. Servo controller 1 and disturbance compensator 3 of servo system
The compensation controller 4 of FIG.
7 is realized by the microcontroller 16 including the control unit 7.

As shown in FIG. 2, the HDD of this embodiment includes a disk 11, a head 10, a head actuator 13, a microcontroller 16, a read / write circuit 21, and a disk controller (HDC) 26.
And One or a plurality of disks 11 (here, one disk is provided for convenience) are provided, and are rotated at a high speed by a spindle motor 12. A large number of concentric tracks are arranged on the disk 11, and each track is provided with a servo sector on which servo information including the servo burst information is recorded.

The head 10 has an MR (magnetore)
Sistive head 10a and recording head 10b formed of an inductive type thin film head are recording / reproducing separation type heads integrated on the same head slider. Head 1
Numerals 0 are provided on both sides of the disk 11, respectively, and are held by the head actuator 13.

The head actuator 13 is driven to rotate about a predetermined rotation axis by the driving force of a voice coil motor (VCM) 14 to move the head 10 in the radial direction of the disk 11. The VCM 14 is a VCM driver 1 controlled by the CPU 17 of the microcontroller 16.
5 is supplied with a drive current to drive.

The read / write circuit 21 is usually composed of a dedicated integrated circuit, and executes data read / write processing. The read / write circuit 21 converts the write data output from the HDC 26 into a recording current by the recording amplifier 23 and outputs it to the recording head 10b. The read / write circuit 21 amplifies a reproduction signal output from the reproduction head 10a by a reproduction amplifier 24 and inputs the amplified signal.
The read data decoded to the original write data is HDC2
6 is output.

As described above, the servo system is a feedback control system for controlling the positioning of the head 10 on a target track (a track including a sector to be accessed) on the disk 11. Specific components include a servo processing circuit 22, a sample and hold circuit 25,
And the microcontroller 16. The servo processing circuit 22 is usually included in an integrated circuit constituting the read / write circuit 21, and extracts servo information (track address information and servo burst information) from a reproduced signal.

The sample and hold circuit 25 samples and holds the position signal level, which is the servo burst information extracted by the servo processing circuit 22. The microcontroller 16 converts the position signal level held by the sample and hold circuit 25 into the A / D converter 1.
8 and converted into a digital value (position information) and input. As described above, the CPU 17 corresponds to the servo controller 1 of FIG.
A position error calculation for calculating a position error with respect to a target position of the head 10 (here, the range of the target track) is executed using the position information input through the control unit 8, and a control amount for eliminating the position error is determined. calculate. The microcontroller 16 converts the control amount calculated by the CPU 17 into a D / A
The signal is converted into an analog signal by the converter 19 and supplied to the VCM driver 15. The CPU 17 executes the head positioning control including the above-described position error calculation processing and the other control of the HDD by a program stored in the memory 20 in advance.

Further, the CPU 17 of the present embodiment executes a disturbance compensation process corresponding to the compensation controller 4 of the disturbance compensation unit 3 as described above. (Operation of Servo System) The configuration and operation of the disturbance compensator 3 will be described below with reference to FIGS.

First, the disturbance compensator 3 comprises a compensation controller 4 and an acceleration sensor 5, as shown in FIG.
The acceleration sensor 5 is a sensor using a piezo element,
As shown in FIG. 4, a sensor body including a support portion 42 formed by etching a silicon member, a beam 41, and a weight 40 is provided inside a package 43 made of glass. The operation principle of the acceleration sensor 5 is as follows.
When acceleration occurs in the direction of arrow Gd due to disturbance, the beam 41 is deformed by the inertia of the weight 40, and this beam 41
The resistance value of the beam 41 changes due to the piezoresistance effect. By detecting the change in the resistance value, the acceleration value is converted into an electric signal. In the present embodiment, such an acceleration sensor 5 is provided on a side surface of a head slider 50 on which the head 10 is mounted, as shown in FIG.

On the other hand, as shown in FIG. 3, the compensation controller 4 detects a detection signal G (acceleration value) from the acceleration sensor 5.
Gain circuit 30 and subtraction circuit 31 for multiplying by a predetermined gain
Having. The subtraction circuit 31 calculates an error between the acceleration value output from the gain circuit 30 and the control amount Sa from the servo controller 1. Here, normally, it can be assumed that the drive input (drive current value) of the VCM 14 and the angular acceleration of the head actuator 13 are proportional to the head actuator mechanism. The output of the gain circuit 30 can be assumed to be the angular acceleration of the head actuator 13 including the acceleration due to disturbance. On the other hand, the control amount S from the servo controller 1
“a” corresponds to the drive input (drive current value) of the VCM 14. Therefore, the compensation controller 4 calculates the angular acceleration (torque disturbance) of the head actuator 13 due to the disturbance.
Is output (compensation value C). Note that the compensation controller 4 is specifically realized by the CPU 17 of the microcontroller 16 as described above. That is, the output of the acceleration sensor 5 is converted into a digital value by the A / D converter 18 and input to the CPU 17.

In such a configuration, the operation of the servo system of this embodiment will be described with reference to the flowcharts of FIGS. 1, 2 and 6 as appropriate. First, the reproducing head 10
It is assumed that a is moved to the target track on the disk 11 and the track following control for positioning within the target track is executed. Reproduction head 10a
Reads the servo information pre-recorded on the track,
Output to the read / write circuit 21. As described above, the servo burst information is extracted by the servo processing circuit 22, and the sample and hold circuit 25 and the A / D converter 1
8 to the CPU 17 (step S8).
1). The CPU 17 calculates a position error between the target position D and the current position P of the reproducing head 10a (Step S2). That is, the servo controller 1 calculates the control amount Sa by inputting the position error information E (step S3).

If no disturbance occurs, the control amount Sa (same value as Sb) of the servo controller 1 is supplied to the head drive mechanism 2 (NO in step S4, S).
8). That is, the CPU 17 converts the calculated control amount into an analog signal (drive control signal) by the D / A converter 19 and supplies the analog signal to the VCM driver 15. Thereby, VC
M14 is supplied with a drive current corresponding to the control amount Sa,
The head actuator 13 is driven. Therefore, the reproducing head 10a moves so as to eliminate the position error and follows the target track.

On the other hand, when disturbance such as vibration or impact is applied, the detection value G detected by the acceleration sensor 5 includes an acceleration component due to the disturbance. The compensation controller 4 inputs the detection value G (the angular acceleration value of the head actuator including the disturbance component) detected by the acceleration sensor 5, and as described above,
A disturbance value (corresponding to the compensation value C) is estimated based on the control amount Sa of the servo controller 1 and the detection value G (YES in step S4, S5, S6). Using this disturbance compensation value C, the control amount Sa of the servo controller 1 is reduced by the subtractor 6 shown in FIG.
(Step S7). Therefore, the head drive mechanism 2 is supplied with a control amount Sb in which disturbance is compensated for the control amount Sa of the servo controller 1. That is, VCM
A drive current corresponding to the control amount Sb is supplied to drive the head actuator 13 (step S14).
8).

As described above, according to the present embodiment, the acceleration sensor 5 and the compensation controller 4 disposed on the head slider 50 add the head actuator 13 to the head actuator 13 during the track following control for causing the head 10 to follow the range of the target track. Estimated disturbance. Compensation controller 4
Outputs the estimated value as a disturbance compensation value C. Therefore,
Using the disturbance compensation value C, the servo controller 1 (CPU
The control amount Sa of 17) can be compensated for to the control amount Sb excluding the disturbance component. Thereby, disturbance compensation in head positioning control can be realized. In this embodiment, the disturbance compensation at the time of track following control has been described. However, the present invention can be applied to seek control at the time of moving the head 10 to a target track. (Second Embodiment) FIGS. 7 and 9 are diagrams related to the second embodiment. In the second embodiment, as shown in FIG.
The two acceleration sensors 5a and 5b are arranged at two positions of the head actuator 13, and the angular acceleration during the rotational driving of the head actuator 13 is detected with high accuracy based on the detection values (Ga, Gb) of the acceleration sensors 5a and 5b. It is a method.
That is, in the first embodiment described above, one acceleration sensor 5
Is provided on a head slider near the head 10 to detect the angular acceleration when the head actuator 13 is driven to rotate.

Here, when a disturbance is applied to the HDD,
The entire HDD may move in a so-called translation direction.
Therefore, the detected value of the acceleration sensor 5 according to the first embodiment includes not only the angular acceleration of the head actuator 13 but also the HD
The influence of the acceleration when the entire D moves is included.
Therefore, the second embodiment is to provide a method that can accurately detect the angular acceleration of the head actuator 13 without being affected by the acceleration when the entire HDD moves.

Hereinafter, the operation of the servo system according to the present embodiment will be described with reference to FIGS. Note that FIG. 1 and FIG. 2 are also applied to the present embodiment, and a description thereof will be omitted. Also in the present embodiment, it is assumed that the reproducing head 10a is moved to a target track on the disk 11 and performs track following control for positioning within the target track. The reproducing head 10a reads the servo information recorded in the track in advance and outputs the read servo information to the read / write circuit 21. As described above, the servo burst information is extracted by the servo processing circuit 22, and is sent to the CPU 1 via the sample and hold circuit 25 and the A / D converter 18.
7 (step S10). The CPU 17 calculates a position error between the target position D and the current position P of the reproducing head 10a (Step S11). That is, the servo controller 1 calculates the control amount Sa by inputting the position error information E (step S12).

Here, when no disturbance occurs, the control amount Sa (same value as Sb) of the servo controller 1 is supplied to the head drive mechanism 2 (NO in step S13, S).
18). That is, the CPU 17 converts the calculated control amount into an analog signal (drive control signal) by the D / A converter 19 and supplies the analog signal to the VCM driver 15. Thereby, V
A drive current corresponding to the control amount Sa is supplied to the CM 14 to drive the head actuator 13. Therefore,
The reproducing head 10a moves so as to eliminate the position error and follows the target track.

On the other hand, when disturbance such as vibration or shock is applied, the control amount Sa of the servo controller 1 includes an acceleration component due to the disturbance. Here, in the present embodiment,
The compensation controller 4 includes two acceleration sensors 5a and 5b
Is input (YES in step S13, S14). The compensation controller 4 calculates the angular acceleration ω of the head actuator 13 based on the detected acceleration values Ga and Gb (Step S15).

The acceleration sensors 5a and 5b are respectively shown in FIG.
As shown in FIG.
It is assumed that they are arranged at the positions of distances La and Lb from the rotation axis 70 of FIG. Further, the acceleration sensors 5a and 5b
It is assumed that the acceleration in the ± Y direction is detected. The compensation controller 4 calculates the angular acceleration ω of the head actuator 13 according to the operation expression shown in the following expression (1). ω = (Gb−Ga) / (Lb−La) (1) Then, the compensation controller 4
The value of the disturbance (corresponding to the compensation value C) is estimated based on the control amount Sa and the angular acceleration ω (step S16). Using the disturbance compensation value C, the subtraction unit 6 shown in FIG.
A control amount Sb obtained by removing a disturbance component from the control amount Sa of the servo controller 1 is calculated (step S17). VCM
A drive current corresponding to the control amount Sb is supplied to the head 14 to drive the head actuator 13 (step S1).
8).

As described above, according to the present embodiment, the angle of the head actuator 13 is controlled by using the detection values of the two acceleration sensors 5a and 5b without being affected by the acceleration when the entire HDD moves. Acceleration ω can be calculated accurately. Therefore, the value of the disturbance (that is, equivalent to the disturbance compensation value C) can be estimated with high accuracy by the angular acceleration ω. For other effects, see the first
This is the same as the embodiment.

Although the arrangement of the two acceleration sensors 5a and 5b has been described for the case shown in FIG. 7, it goes without saying that other positions may be used. However, the relational expression (1) for calculating the respective accelerations is changed according to the arrangement of the acceleration sensors 5a and 5b. (Modification of Second Embodiment) FIG. 8 shows a modification of the second embodiment, in which the angular acceleration sensor 80 is arranged on the rotation shaft 70 of the head actuator 13. The angular acceleration sensor 80 is basically the same as the one using the two acceleration sensors 5a and 5b. Even in such a configuration, as in the second embodiment, the angular acceleration ω of the head actuator 13 can be accurately calculated without being affected by the acceleration when the entire HDD moves.

[0036]

As described above in detail, according to the present invention, when disturbance such as external vibration or impact occurs in a disk recording / reproducing apparatus such as an HDD, the disturbance acting on the head actuator mechanism is obtained. And so-called disturbance compensation processing can be executed based on the estimation result. Accordingly, it is possible to realize effective disturbance compensation at the time of head positioning control without increasing the servo band or requiring a vibration isolation mechanism as in the related art. This allows
As a result, it is possible to realize a servo system having excellent vibration proof characteristics without causing any special structural devising by the vibration isolation mechanism or lowering of the disk format efficiency due to an increase in the servo band. For example, this servo system is HD
When applied to D, it is possible to provide an apparatus having excellent vibration proof characteristics without hindering higher recording density.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a servo control system related to a first embodiment of the present invention.

FIG. 2 is an exemplary block diagram showing a main part of the HDD related to the embodiment;

FIG. 3 is an exemplary block diagram showing a configuration of a disturbance compensation controller related to the embodiment;

FIG. 4 is an exemplary view showing the structure of an acceleration sensor according to the embodiment.

FIG. 5 is a view showing a mounting position of the acceleration sensor according to the embodiment;

FIG. 6 is an exemplary flowchart for explaining the operation of the servo system according to the embodiment;

FIG. 7 is a view showing a mounting position of an acceleration sensor according to the second embodiment.

FIG. 8 is a diagram showing a modification of the second embodiment.

FIG. 9 is a flowchart for explaining the operation of the servo system according to the second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Servo controller (feedback controller) 2 ... Head drive mechanism (head actuator mechanism) 3 ... Disturbance compensation part 4 ... Compensation controller 5, 5a, 5b ... Acceleration sensor 6 ... Subtraction part 10 ... Head (recording / reproduction separation type head) 10a reproduction head 10b recording head 11 disk 12 spindle motor 13 head actuator 14 voice coil motor (VCM) 15 VCM driver 16 microcontroller 17 CPU 18 A / D converter 19 D / A converter Reference Signs List 20 memory 21 read / write circuit 22 servo processing circuit 23 recording amplifier 24 reproduction amplifier 25 sample hold circuit 26 disk controller (HDC) 70 rotary axis 80 angular acceleration sensor

Claims (10)

[Claims] 1. A disk recording and reproducing apparatus for recording and reproducing data on and from a disk by positioning a head at a target position on the disk, comprising: a head moving mechanism for moving the head in a radial direction of the disk. A sensor unit provided in the head moving mechanism for detecting a disturbance acting at the time of the head positioning control; and the head moving mechanism based on head position error information with respect to a target position at the time of the head positioning control. Servo means for calculating a control amount, and disturbance compensation means for estimating the disturbance based on the detected value of the sensor means and the control amount calculated by the servo means, and eliminating the disturbance from the control amount. A disk recording / reproducing apparatus characterized by comprising: 2. The disk recording / reproducing apparatus according to claim 1, wherein said sensor means comprises an acceleration sensor, and is arranged near said head and has a function of detecting an acceleration value in a predetermined direction. 3. The disturbance compensating means calculates an error between a detection value output from the sensor means and the control amount,
3. The disk recording / reproducing apparatus according to claim 1, further comprising means for estimating the disturbance from the error. 4. The sensor means comprises a plurality of acceleration sensors, and is arranged at a plurality of predetermined positions of the head moving mechanism, and is provided with each acceleration value detected by each of the acceleration sensors and a position of each of the acceleration sensors. Based on the angular acceleration and the control amount calculated by the servo means, wherein the disturbance compensation means calculates the disturbance based on the angular acceleration and the control amount calculated by the servo means. 2. The disk recording / reproducing apparatus according to claim 1, further comprising means for estimating. 5. The sensor means comprises an angular acceleration sensor, and is disposed near a rotation axis of the head moving mechanism.
5. The disk recording / reproducing apparatus according to claim 4, further comprising a function of detecting an angular acceleration value in a predetermined direction. 6. A head positioning control system applied to a disk recording / reproducing apparatus for recording / reproducing data on / from the disk by positioning a head at a target position on the disk, the head positioning control system comprising: Using a head actuator mechanism for rotating and moving in a radial direction, and servo information reproduced from the disk by the head, calculating a position error between a target position where the head should be positioned on the disk and a current position. Means for performing a drive control of the head actuator mechanism based on the position error to calculate a first control amount for positioning control of the head at the target position; provided in the head actuator mechanism. An acceleration sensor for detecting a disturbance acting during the positioning control of the head. Means for estimating the disturbance based on an acceleration detection value of the acceleration sensor means and the first control amount, and calculating a second control amount in which the estimated disturbance is eliminated from the first control amount And a means for converting the first or second control amount into a drive control signal to drive and control the head actuator mechanism. 7. The acceleration sensor means comprises a plurality of acceleration sensors, and is arranged at a plurality of predetermined locations of the head actuator mechanism. Each acceleration value detected by each of the acceleration sensors and a position of each of the acceleration sensors are provided. And a means for estimating the disturbance based on the angular acceleration and the first control amount. 7. The head positioning control system according to claim 6, wherein: 8. The apparatus according to claim 1, wherein said acceleration sensor means comprises an angular acceleration sensor, and is disposed near a rotation axis of said head actuator mechanism, and has a function of detecting an angular acceleration value in a predetermined direction. 7. The head positioning control system according to item 6. 9. A disk recording apparatus having servo control means for controlling the positioning of a head at a target position on a disk based on servo information prerecorded on the disk, wherein the head records and reproduces data on the disk. A head positioning control method applied to a reproducing apparatus, comprising: a head actuator mechanism for holding and rotating the head in a radial direction of the disk; and Acceleration sensor means for detecting an acting disturbance, wherein the servo control means uses a servo information reproduced from the disk, and a target position and a current position where the head is to be positioned on the disk. Calculating a position error with the head, based on the position error. Calculating a first control amount for controlling the positioning of the head at the target position by driving and controlling the actuator mechanism; and calculating the first control amount based on an acceleration detection value of the acceleration sensor means and the first control amount. Estimating a disturbance; calculating a second control amount in which the estimated disturbance is eliminated from the first control amount; converting the second control amount into a drive control signal to convert the head control into a drive control signal; A head positioning control method, comprising: performing a process of controlling driving of a head. 10. A disk recording apparatus having servo control means for controlling the positioning of a head at a target position on a disk based on servo information prerecorded on the disk, wherein the head records and reproduces data on the disk. A head positioning control method applied to a reproducing apparatus, comprising: a head actuator mechanism for holding the head and rotating the disk in a radial direction of the disk; and a head actuator mechanism provided in the head actuator mechanism for rotating the head actuator mechanism. Acceleration sensor means for detecting angular acceleration during operation, the servo control means, using servo information reproduced from the disk, a target position for positioning the head on the disk Calculating a position error with respect to the current position; based on the position error Calculating a first control amount for driving and controlling the head actuator mechanism to control the positioning of the head at the target position; and calculating a first control amount and an angular acceleration detection value of the acceleration sensor means. Estimating the disturbance on the basis of the first control amount, calculating a second control amount that eliminates the estimated disturbance from the first control amount, and converting the second control amount into a drive control signal. And a step of controlling the drive of the head actuator mechanism.