JP2003272328A - Disk storage device and head positioning control method - Google Patents

Abstract

(57) [Problem] To provide a disk storage device capable of improving head positioning accuracy in a head positioning control system including a disturbance feedforward control system by adapting to fluctuations in disturbance. is there. A disk drive having a head positioning control system including a disturbance feed-forward (FF) control system is disclosed. The system (CPU 70)
Is a disturbance F for observing the acceleration of the disturbance with the acceleration sensor 9 and compensating for the deterioration of the positioning accuracy due to the disturbance.
Implement the F control function. Separately from this disturbance FF control function, the system is based on disturbance and position error.
It has a parameter identification function for updating the transfer characteristics of the disturbance FF control system.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates generally to the field of disk storage devices, and more particularly to head positioning control systems.

[0002]

2. Description of the Related Art Conventionally, in a disk storage device represented by a hard disk drive (hereinafter referred to as a disk drive),
A head positioning control system for positioning a head (magnetic head) at a target position (track to be accessed) on a disk which is a data recording medium is provided. The head performs a data read / write operation on the disk.

A head positioning control system controls a voice coil motor (VCM) of an actuator in which a head is mounted by a feedback control system using a CPU as a controller to execute head follow-up control with respect to a target position. . In such a system, a method has been developed or proposed in which a disturbance feedforward control system is provided to suppress the influence of external vibration or shock (hereinafter referred to as disturbance) applied to the drive.

The disturbance feedforward control system calculates a compensation value for suppressing the influence of the disturbance based on the acceleration value of the disturbance detected (observed) by the acceleration sensor provided in the drive. With this disturbance feedforward control system, it is possible to absorb fluctuations caused by disturbance during head follow-up control.

[0005]

If a head positioning control system including a disturbance feedforward control system is used,
Since the compensating function for the disturbance applied during the drive of the disk drive can be realized, the head positioning accuracy can be improved.

The performance of the disturbance feedforward control system depends on the setting of the transfer characteristic (F) to be set. Usually, the transfer characteristic F is the acceleration fluctuation characteristic of the disturbance (transfer characteristic K), the position fluctuation characteristic due to the disturbance (transfer characteristic W), the characteristic of the actuator including the VCM which is the control target (transfer characteristic P) (stiffness, resonance). , Attenuation rate) etc. Furthermore, in an actual disk drive, there are mechanical variations for each drive product, the mounting angle of the acceleration sensor, the relative angle of the head positioning position, the direction of the external force for exciting the disturbance, and the secular change. The transfer function (K, W, P) at changes.

However, generally, during the manufacturing process of the disk drive, the transfer characteristic F of the disturbance feedforward control system is fixedly set and is not updated after the product is shipped. Therefore, when the disk drive is actually used, there is a possibility that the effect of the head positioning accuracy with respect to the disturbance may greatly vary due to mechanical variations and environmental changes among individual products.

Therefore, an object of the present invention is to make it possible to determine the transfer characteristics of the disturbance feedforward control system so as to adapt to environmental changes during use and mechanical variations among products, so that head positioning accuracy with respect to disturbance can be improved. It is to provide a disk storage device capable of stably ensuring the improvement of

[0009]

SUMMARY OF THE INVENTION An aspect of the present invention relates to a disk storage device (disk drive) using a head positioning control system for executing follow-up control by a feedback control system and disturbance compensation by a disturbance feedforward control system. . The system includes a parameter identification function for updating the transfer characteristic of the disturbance feedforward control system in accordance with the disturbance to be observed when the disk storage device is used.

A disk storage device according to an aspect of the present invention is a disk storage device having a head positioning control system for positioning a head at a target position on a disk which is a data recording medium. A tracking control means for performing positioning control with an actuator mechanism for moving the head as a control target based on a positional error between the current position of the head and the target position; and a disturbance corresponding to vibration or impact applied from the outside. Disturbance detection means, feedforward control means for executing feedforward control for suppressing the influence of the disturbance on the control operation of the tracking control means, disturbance characteristic value detected by the disturbance detection means, and the position The transmission of the feedforward control means based on the error It is obtained by a parameter identification means for performing the parameter identification processing of determining sex.

With the head positioning control system having such a configuration, when the disk drive is used, the process for identifying the parameter for determining the transfer characteristic of the disturbance feedforward control system adapted to the observed disturbance is executed. In other words, the parameter identification mode can be executed separately from the control execution mode of the disturbance feedforward control system. Therefore, after shipping the disk drive product, it is possible to update the transfer characteristic of the disturbance feedforward control system so as to adapt to environmental changes during use and mechanical variations between products. Therefore, in the actual use environment, it is possible to stably ensure the improvement of the head positioning accuracy against the disturbance.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(Structure of Disk Drive) As shown in FIG. 1, the disk drive of this embodiment has a disk 1 as a data recording medium and a spindle motor (SPM) 2.
And a head 3 for executing data read / write operations
And an actuator 4.

The disk 1 is rotated by the SPM 2. The disc 1 is provided with a large number of concentric tracks 100 on its surface. Each track 100 has a predetermined number of servo areas 10 arranged at predetermined intervals in the circumferential direction.
1 is included. In the servo area 101, servo information used for detecting the position of the head 3 in the head positioning control system during normal read / write operation is recorded.

In the head 3, a read head and a write head are usually mounted separately on a slider. The actuator 4 has the head 3 mounted thereon, and the driving force of a voice coil motor (VCM) 5 moves the head 3 in the radial direction of the disk 1. The VCM 5 is a control target in a narrow sense in the head positioning control system and is a main element of the actuator mechanism.

Further, the disk drive includes a read / write channel 6, a microcontroller 7, and a VCM.
It has a driver 8 and an acceleration sensor 9. The read / write channel 6 has a signal processing circuit 60 that processes a read signal corresponding to servo information or user information read from the read head included in the head 3 or a write signal. The read / write channel 6 also includes a position detection circuit 61 that extracts servo information from the read signal and generates a position detection signal for detecting the position of the head 3.

The microcontroller 7 includes a microprocessor (CPU) 70, which is the main element of the head positioning control system, and its program (firmware).
And a ROM 71 that stores various control parameters. The CPU 70 realizes the feedback control system and the disturbance feedforward control system of the head positioning control system by executing the program stored in the ROM 71. The VCM driver 8 is the CPU 70
A drive current corresponding to the control operation amount (including the compensation value by the disturbance FF controller) from is generated and supplied to the VCM 5.

The acceleration sensor 9 detects the acceleration (disturbance value) of the disturbance (exciting external force) corresponding to the vibration or shock applied to the disk drive, and outputs the detection signal to the acceleration signal processing circuit 10. The acceleration signal processing circuit 10 has a filter (LPF or the like) that amplifies the detection signal from the acceleration sensor 9 and reduces noise. The A / D converter 11 converts the acceleration signal into an acceleration value (denoted as A) which is a digital value, and outputs it to the CPU 70.

(Head Positioning Control System) The configuration and operation of the head positioning control system according to this embodiment will be described below with reference to FIGS. 2 to 12.

First, the principle operation of the system will be described with reference to FIG.

As described above, the system has the CPU 7
It is realized by 0. The CPU 70 synchronizes the current position of the head 3 with the position detection circuit 6 in synchronization with the rotation angle of the disk 1.
Get from 1. The CPU 70 also constitutes a sample value control system that calculates a control operation amount (defined as a control value u) to be input to the controlled object 81 (VCM 5) at a constant time interval (servo cycle). The drive current value supplied to the VCM 5 is preset with a limit value by the VCM driver 8.

In this system, a follow-up controller (transfer function C) 80 constituting a feedback control system outputs a control value calculated at a predetermined servo cycle (sampling interval) to a controlled object 81, and the head position on the disk. Follows the target position (R).

On the other hand, the disturbance feedforward control system is
The disturbance feedforward controller (hereinafter referred to as FF controller) 88 is a main element. FF controller 88
Acquires the acceleration value (A) of the disturbance (excitation external force) observed by the disturbance observing section 82 (that is, the acceleration sensor 9) at the timing when the current position of the head is obtained.

In this system, the position error (e) due to the disturbance (A) is controlled by the disturbance feedforward control system.
This is a method of compensating for the effect on. Here, the transfer function from the disturbance detection (acceleration value A) to the head position error (e) can be expressed by the following equation (1).

[0025]

[Equation 1]

Here, P is the transfer characteristic of the controlled object 81, and C is the transfer characteristic of the follow-up controller 80. Further, W is the position variation characteristic (85) of the disturbance, and shows the transfer characteristic from the disturbance value (A) to the target position variation (r).
This target position variation (r) occurs because the drive housing or the disk 1 is deformed by the disturbance and the track followed by the follow-up controller 80 moves. Further, K is the acceleration fluctuation characteristic (86) of the disturbance, and the acceleration value (d) of the disturbance equivalently added to the control value (u) from the disturbance value (A).
The transfer characteristics up to are shown.

Disturbance (A) with respect to head position error (e)
In order to suppress the influence of the above, the transfer characteristic F of the disturbance FF controller 88 may be set as shown in the following expression (2) so that the numerator term of the expression (1) becomes zero.

[0028]

[Equation 2]

The system may be a system in which the disturbance feedforward control system compensates the influence of the disturbance (A) on the control input value (u) from the follow-up controller 80. In this case, in the transfer function from the disturbance detection (acceleration value A) to the head position error (e), the numerator of the right term of the formula (1) is “W-KP-FP”. Also, the disturbance F
In the transfer characteristic F of the F controller 88, the denominator of the right term of the equation (2) is “P”.

Next, a parameter identifying method for determining the transfer characteristic (F) of the disturbance FF controller 88 will be described with reference to FIG. This method uses the so-called least squares method. FIG. 2 has an identification target 201 (transfer function B) corresponding to the FF controller 88 and a parameter identifier 202 (transfer function Q) as elements.

The parameter identifier 202 is used to identify the identification target 20.
Input (u) of the identification target 201, where 1 is a discrete system
The transfer characteristic is estimated from the relationship between the output and the output (y). This relationship is expressed by the following equation (3).

[0032]

[Equation 3]

Here, a is a coefficient parameter on the output side of the parameter identifier 42, and b is a coefficient parameter on the input side thereof. k is the number of steps in the discrete system.

Further, the unknown parameter vector θ and the input / output vector ζ (k) are defined by the following equation (4).

[0035]

[Equation 4]

From this definition, the equation (3) can be expressed as the following equation (5).

[Equation 5]

Here, using the estimated value of the unknown parameter at the time (k-1), the identification model as shown in the following equation (6) can be calculated.

[0038]

[Equation 6]

The identification error can be expressed by the following equation (7).

[Equation 7]

The parameter vector θ can be estimated by the least-squares method by using the measurement data y (k) and ζ (k) up to the time k by an evaluation function as shown in the following equation (8).

[0041]

[Equation 8]

Methods for determining the parameter vector θ include offline identification, which requires all past data to calculate an estimated value, and online identification, which sequentially estimates each identification step of a discrete system. In determining the transfer function (F) of the disturbance FF controller 88, the latter with a small amount of data is desirable.

Specifically, using a square matrix Γ (k) of degree (2n + 1), the following equation (9) is obtained for each identification step.
To calculate.

[0044]

[Equation 9]

The initial value of Γ (k) is “Γ (0) = γI” from the positive constant (γ) and the unit matrix (I).

[0046]

[Equation 10]

On the basis of the above principle, the parameter identifier 202 executes the identification processing step (here, k) as shown in the flowchart of FIG. 4 or FIG. 5, and the transfer function (F) of the disturbance FF controller 88. To estimate.

The parameter identifier 202 is used by the identification target 20.
1. Input (u) and output (y) of 1 are acquired (step S
1 or S10). Hereinafter, the parameter identifier 202 is
The calculation of the equation (4) is executed (step S2 or S
11). Next, the calculation of the equations (6) and (7) is executed (step S3 or S12). Further, the calculation of the equation (10) is executed (step S4 or S1).
3). Then, the calculation of the equation (9) is executed for each identification step (step S5 or S14).

Here, if the count number (N) of the identification step is larger than the sufficiently large constant (S), the parameter identifier 202 ends the identification process (Y in step S6).
ES). Otherwise, the parameter identifier 202
The identification step is continued (NO in step S6, S
7). Further, the parameter identifier 202 may determine the end of the identification process based on the amount of change (degree of change v) of the parameter estimation value with respect to the previous sample (k−1) (the method of FIG. 5). That is, the parameter identifier 202 uses the following equation (1
1) is calculated (step S15).

[0050]

[Equation 11]

The parameter identifier 202 determines the degree of change (v)
If is sufficiently smaller than the constant (z), the identification process ends (YES in step S16). Otherwise, the parameter identifier 202 continues the identification step (NO in step S16, S17).

Next, as shown in FIGS. 6 and 7, when the filter 204 (input filter H) is provided on the input side (b) of the parameter identifier 202 and the filter 205 (on the output side (a) thereof). A parameter identification method when the output filter J) is provided will be described.

Each of the filters 204 and 205 has the above equation (3).
Is a discrete system itself, and the transfer characteristic is expressed by the following equation (12).

[0054]

[Equation 12]

Here, as shown in FIG. 6, the input side (b)
When the filter 204 (input filter H) is provided in, the parameter identifier 202 identifies a transfer function represented by the following equation (13).

[0056]

[Equation 13]

Further, as shown in FIG. 7, when a filter 205 (output filter J) is provided on the output side (a),
The parameter identifier 202 identifies a transfer function represented by the following equation (14).

[0058]

[Equation 14]

As described above, the parameter identifier 202
Are filters 204 (H) and 205 (J) on the input / output side.
By arranging, the transfer function of a discrete system different from that of the identification target 201 (B) can be identified while using the input / output signals applied to the identification target 201 (B).

Generally, in the parameter identification by the least squares method, the convergence speed differs depending on the frequency characteristic of the identification object 201, and the convergence time becomes very long when the frequency element is close to the integral element. The information of the identification target 201 is
It is relatively easy to predict at low frequency components. Therefore,
Identification input / output filters 204, 20 using known information
5, the parameter identifier 20 for only high frequency elements
Estimating by 2 is a practically effective method.

In the parameter identification, the above equation (3) is used.
The calculation processing amount is determined by the order of the discrete system shown in, and the calculation amount increases with the square of the number of parameter estimations. Therefore, the information of the known identification target 201 is added to the input / output filters 204 and 205 for identification, and the unknown identification target 20 is added.
It is possible to reduce the order and the amount of calculation by identifying only the characteristic of 1.

Here, the transfer function B of the identification target 201 is defined as shown in the following equation (15), where the known part of the identification target 201 (B) is Bm and the unknown part is Bn.

[0063]

[Equation 15]

When the filter 204 (H) is provided on the input side, the relationship shown in the following equation (16) is established.

[0065]

[Equation 16]

When the filter 205 (J) is provided on the output side, the relation shown in the following equation (17) is established.

[0067]

[Equation 17]

Therefore, the parameter identifier 202 can estimate only the unknown part Bn of the identification object 201. Known part Bm
Is stable, as shown in the equation (16),
A method in which a filter 204 (H) is provided on the input side is effective. On the other hand, when the known portion Bm is unstable and “1 / Bm” becomes stable, the method of providing the filter 205 (J) on the output side as shown in the above expression (17) is effective. .

(Head Positioning Control System Including Parameter Identifier) FIG. 8 is a block diagram showing a main part of a system including a parameter identifier 83 for executing the above-described parameter identifying method.

In this system, the disturbance value (acceleration value A) observed (detected) by the disturbance observing section 82 is applied to the input side of the parameter identifier 83 via the input filter 84 (transfer function H) for identification. It is a configuration that is done. Furthermore, a signal indicating the position error (e) between the head position and the target position (R) is applied to the output side of the parameter identifier 83.

Here, it is assumed that the disturbance feedforward control system (disturbance FF controller 88) to be identified is a system that compensates the control value (u) output from the follow-up controller 80. In the system, the transfer function H of the input filter 84 can be expressed as shown in the following equation (18).

[0072]

[Equation 18]

From the equation (18), the equation (13) and the transfer function "(W-KP) / (1 + CP)" from the disturbance (A) to the position error (e) of the system, the following equation (19) is obtained.
The relational expression shown in is required.

[0074]

[Formula 19]

That is, the calculation result (Q) is the transfer characteristic F (F = (W-KP) / P) of the disturbance FF controller 88.
Matches In the equation (18), the transfer function C of the tracking controller 80 is known. In addition, the control target 81
Also in the disk drive, the transfer function P of is compared with the acceleration fluctuation characteristic K of the disturbance and the position fluctuation characteristic W of the disturbance,
It is a value that can be easily obtained.

Further, in the system in which the position error (e) is compensated by the disturbance feedforward control system (disturbance FF controller 88), the transfer function H of the input filter 84 is expressed as shown in the following equation (20). it can.

[0077]

[Equation 20]

From the equation (18), the equation (13) and the transfer function "(W-KP) / (1 + CP)" from the disturbance (A) to the position error (e) of the system, the following equation (21) is obtained.
The relational expression shown in is required.

[0079]

[Equation 21]

That is, the calculation result (Q) matches the transfer characteristic F of the disturbance FF controller 88 shown in the equation (2).

9 and 10 are block diagrams showing the configuration of a head positioning control system including the parameter identifier 83 and the disturbance FF controller 88.

The system shown in FIG. 9 is a system in which the disturbance FF controller 88 compensates for the control value (u) output from the follow-up controller 80. The system shown in FIG. 10 is a system in which the position error (e) is compensated by the disturbance FF controller 88. Either way,
The identification end determination unit 87 is configured to control the identification processing of the transfer characteristic (F) of the disturbance FF controller 88 by the parameter identifier 83 and the control execution of the disturbance FF controller 88 after identification.

Referring to the flowchart of FIG. 11 below,
The operation of the system shown in FIG. 9 or 10 will be described.

When the head positioning control (servo control) operation of the disk drive is started, the system (that is, the CPU 70) causes the position error (e) between the current head position and the target position (R), and the acceleration sensor 9. The disturbance value (acceleration value A) by the (disturbance observation unit 82) is observed (step S20). Here, in the first sample (servo period), the identification mode of the disturbance feedforward control system is assumed (YES in step S21).

That is, as shown in FIG. 9 or 10, the output of the disturbance FF controller 88 is off and the output of the parameter identifier 83 is on. The tracking controller 80 executes the tracking control calculation based on the observed position error (e) to calculate the control value (u) (step S23). The parameter identifier 83 executes the filter operation as shown in the above equation (18) or equation (20) (YES in step S24, S25). And
The parameter identifier 83 executes the identification step as shown in FIG. 4 or FIG. 5, and determines the end of the parameter identification processing (steps S26 and S27).

When the identification process is completed, the parameter identifier 83 updates the parameters of the disturbance FF controller 88 and newly identifies the transfer function (F) adapted to the disturbance (step S28). Then, from the next sample, the disturbance FF controller 88 enters the control execution mode, and the disturbance F
The output of the F controller 88 is on and the output of the parameter identifier 83 is off (step S2).
9).

In the control execution mode of the disturbance FF controller 88, the disturbance FF controller 88 executes the control calculation and the control value (u) or the position error (e) due to the disturbance (A).
Is compensated for (NO in step S21, S22).
Further, in the control execution mode of the disturbance FF controller 88, the CPU 70 executes the evaluation of the head positioning accuracy, and when it determines that the accuracy is degraded, the CPU 70 shifts to the re-execution of the identification mode from the next sample (step S3).
0, S31).

As described above, according to the system of the embodiment, in the actual servo control in the disk drive, the parameter identification mode for determining the transfer function of the disturbance feedforward control system and the disturbance feedforward control system. The control execution modes of and are executed separately. Therefore, it is possible to update the transfer characteristic (parameter) so as to enable the compensation function of the disturbance feedforward control system against disturbance by adapting to the usage environment of the disk drive or mechanical variations among products. . Therefore, in the actual environment in which the disk drive is used, it is possible to stably ensure the improvement of the head positioning accuracy against disturbance.

FIG. 3 shows the effect of the system, showing temporal changes in the identification parameter (characteristic 300) and the head positioning accuracy (characteristic 301). TP indicates the time when the identification determination ends, and the time when the parameters of the disturbance feedforward control system are updated. Head positioning accuracy characteristics 3
01 indicates that the accuracy has improved since the identification determination end time point TP.

[0090]

As described above in detail, according to the present invention, in the disk drive including the head positioning control system having the disturbance feedforward control system, the control execution mode of the disturbance feedforward control system is separated,
It has the identification mode of the transfer characteristic of the disturbance feedforward control system. Therefore, it is possible to identify the transfer characteristic of the disturbance feedforward control system so as to adapt to the environmental change when the drive is used and the mechanical variation for each product.
Thereby, it is possible to stably ensure the improvement of the head positioning accuracy with respect to the disturbance.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main part of a disk drive according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining a parameter identification method of a disturbance feedforward control system according to the same embodiment.

FIG. 3 is a diagram for explaining characteristics of the head positioning control system according to the embodiment.

FIG. 4 is a flowchart for explaining a parameter identification method according to the same embodiment.

FIG. 5 is a flowchart for explaining a parameter identification method according to the same embodiment.

FIG. 6 is a first parameter identification method according to the first embodiment.
For explaining a modified example of FIG.

FIG. 7 is a second parameter identification method according to the embodiment.
For explaining a modified example of FIG.

FIG. 8 is a block diagram showing a configuration of a head positioning control system including a parameter identifier according to the same embodiment.

FIG. 9 is a block diagram showing a configuration of a head positioning control system to which a parameter identification method according to the same embodiment is applied.

FIG. 10 is a block diagram showing a configuration of a head positioning control system to which a parameter identification method according to the same embodiment is applied.

FIG. 11 is a flowchart for explaining the operation of the head positioning control system according to the same embodiment.

FIG. 12 is a block diagram for explaining a principle configuration of a head positioning control system according to the same embodiment.

[Explanation of symbols]

1 ... Disc 2… Spindle motor (SPM) 3 ... Head 4 ... Actuator 5 ... Voice coil motor (VCM) 6 ... Read / write channel 7 ... Micro controller 8 ... VCM driver 9 ... Acceleration sensor 10 ... Acceleration signal processing circuit 11 ... A / D converter 70 ... CPU 71 ... ROM 80 ... Follow-up controller 83 ... Parameter identifier 84 ... Filter 88 ... Disturbance feed forward (FF) controller

Continued front page    F-term (reference) 5D088 BB11 MM09                 5D096 AA02 CC01 DD09 EE03 GG07                       HH18 KK12                 5H004 GA15 GB15 GB20 HA07 HB07                       JA03 JB01 KA32 KB01 KB33                       KC43 KC45 KC55 LA02 LA12                       MA12                 5H303 AA22 BB02 BB06 BB11 CC02                       CC07 DD01 EE03 FF03 KK01                       KK25 KK29 LL03 MM05

Claims (16)

[Claims] 1. A disk storage device having a head positioning control system for positioning and controlling a head at a target position on a disk which is a data recording medium, wherein the head positioning control system comprises a current position of the head and the target position. Tracking control means for performing positioning control with an actuator mechanism for moving the head as a control target based on a position error between the head, and disturbance detection means for detecting a disturbance corresponding to vibration or shock applied from the outside, The feedforward control means for executing feedforward control for suppressing the influence of the disturbance on the control operation of the follow-up control means, and the execution mode of the feedforward control are separated and detected by the disturbance detection means. Based on the disturbance characteristic value and the position error, Disk storage, characterized in that it comprises a identification mode means for performing the parameter identification processing to determine the transfer characteristic of the feedforward control unit. 2. The disk storage device according to claim 1, wherein the disturbance detection means includes an acceleration sensor that detects acceleration as a disturbance characteristic value. 3. The identification mode means, based on the position error and the calculation result of a filter calculation according to the transfer characteristics of the controlled object and the follow-up control means to which the disturbance characteristic value is input, and the position error. The disk storage device according to claim 1, wherein the disk storage device is configured to perform an identification process. 4. The feedforward control means generates a compensation signal for absorbing a variation generated in the control operation of the tracking control means due to the disturbance, based on an acceleration value corresponding to the disturbance characteristic value. The disk storage device according to claim 1, wherein the disk storage device is configured as described above. 5. An identification end determination means for determining the end of the parameter identification processing by the identification mode means, the identification end determination means having the function of the feedforward control means during execution of the parameter identification processing. 2. The configuration is made such that it is invalidated, and the transfer characteristic can be updated and the feedforward control can be executed for the feedforward control means after the parameter identification processing is completed. 4. The disk storage device according to any one of 4 above. 6. The feedforward control means is configured to execute feedforward control for compensating for a variation due to the disturbance from the position error which is an input of the tracking control means. The disk storage device according to any one of claims 1 to 5. 7. The identification mode means outputs a calculation result of a filter calculation corresponding to a complementary sensitivity function of a closed loop transfer characteristic of the controlled object and the follow-up control means to which the disturbance characteristic value is input and the position error. Based on the above, the parameter identification processing is executed, and the feedforward control means is configured to execute the feedforward control for compensating the fluctuation due to the disturbance from the position error which is the input of the tracking control means. The disk storage device according to any one of claims 1 to 5, wherein 8. The feedforward control means is configured to execute a feedforward control for compensating for a variation caused by the disturbance from a control operation amount output from the tracking control means. The disk storage device according to any one of claims 1 to 5. 9. The identification mode means is a filter corresponding to a transfer characteristic obtained by multiplying a sensitivity function of a closed loop transfer characteristic of the controlled object and the follow-up control means to which the disturbance characteristic value is input by a transfer function of the controlled object. Based on the calculation result of the calculation and the position error, the parameter identification processing is executed, and the feedforward control means compensates the fluctuation due to the disturbance from the control operation amount which is the output of the tracking control means. 1 to 5 are configured to execute the feed forward control of
The disk storage device according to claim 1. 10. A head positioning control method applied to a disk storage device having a head positioning control system for positioning and controlling a head at a target position on a disk which is a data recording medium, wherein the head positioning control system comprises: A tracking control function for executing positioning control with an actuator mechanism for moving the head as a control target based on a position error between the current position of the head and the target position, and a disturbance corresponding to vibration or shock applied from the outside. Disturbance detection function for detecting the, the feedforward control function for executing the feedforward control for suppressing the influence of the disturbance on the control operation of the tracking control means, and the execution mode of the feedforward control are separated. , The disturbance characteristic value detected by the disturbance detection function and On the basis of the serial position error, head positioning control method characterized by comprising the identification mode function to perform parameter identification process for determining the transfer characteristic of the feedforward control. 11. The identification mode function, based on the position error and the calculation result of a filter calculation in accordance with the transfer characteristics of the control target and the tracking control function, which receives the disturbance characteristic value as an input, and the parameter based on the position error. The head positioning control method according to claim 10, wherein the head positioning control method is configured to execute an identification process. 12. The head positioning control system, when executing an identification mode, performing the parameter identification process by the identification mode function, determining the end of identification, which is the end of the parameter identification process, After completion, it is configured to perform a process including a step of updating a transfer characteristic for the feedforward control function, and a step of enabling the feedforward control function after execution of the updating step. The head positioning control method according to claim 10. 13. The feedforward control function comprises:
The head positioning control method according to any one of claims 10 to 12, wherein feedforward control for compensating for a variation due to the disturbance is performed from the position error. . 14. The identification mode function includes a calculation result of a filter calculation corresponding to a complementary sensitivity function of a closed loop transfer characteristic of the control target and the follow-up control function to which the disturbance characteristic value is input, and the position error. Based on the above, the parameter identification process is executed, and the feedforward control function is configured to execute the feedforward control for compensating the fluctuation due to the disturbance from the position error. The head positioning control method according to any one of claims 10 to 12. 15. The feedforward control function comprises:
The feedforward control for compensating for the variation due to the disturbance is executed from the control operation amount calculated by the tracking control function, and the feedforward control is executed. A head positioning control method according to item. 16. The filter, wherein the identification mode function is equivalent to a transfer characteristic obtained by multiplying a sensitivity function of a closed loop transfer characteristic of the control target and the tracking control function, to which the disturbance characteristic value is input, by a transfer function of the control target. The result of the operation,
The parameter identification processing is executed based on the position error, and the feedforward control function executes feedforward control for compensating for a variation due to the disturbance from the control operation amount calculated by the tracking control function. The head positioning control method according to claim 10, wherein the head positioning control method is configured to: