KR100254911B1 - Pickup movement control device and method - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc servomechanism, and more particularly, to accurately recognize information about a speed of a sled motor and a moving distance of a pickup during track jump and seek. By controlling the driving speed of the sled motor by referring to the optimum sampling data for the acceleration section and the deceleration section, and controlling the speed of the sled before the brake section to decelerate to an appropriate speed in advance, the stabilization time of the pickup after the brake section The present invention relates to a pick-up movement control apparatus and method, which is shortened to improve data access time and to reduce data error during pickup.

Description

Pickup movement control device and method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a servo mechanism of an optical disk device. In particular, a pickup device is moved to a desired position by using a sled motor in order to search for a target address in an apparatus employing an optical disk, and is scattered scattered here and there. The present invention relates to a pickup movement control apparatus and method for controlling the speed of the sled motor so that when the sled motor is moved at high speed to retrieve data, the pickup movement is stabilized and the desired address is accurately searched.

In general, the timing setting of the kick pulse and the brake pulse for driving the sled motor for moving the pickup is configured in such a manner that the timing of the kick pulse is varied according to the moving distance of the pickup with respect to the fixed brake pulse timing.

When the sled motor is driven by the kick pulse and the brake pulse, the sled motor is driven at a constant speed when the distance to which the pickup is to be moved exceeds a certain distance. Therefore, it is necessary to stop the sled motor in operation. The force is almost constant regardless of the distance traveled.

1 is a block diagram showing a general optical application device, wherein a pickup unit 1, a driver unit 5, an RF signal reproducing unit 7, a data processing unit 9, a system control unit 11, and a servo are shown. The control unit 13 and the AV decoder unit 15 are included.

On the other hand, the pickup section 1 is constituted by a pickup 3 which detects data from the optical disc 2 on which data is recorded in accordance with a predetermined playback command signal, and the driving section 5 is in accordance with a predetermined control signal. It is configured to rotate the disk of the pickup section 1 and to perform tracking, focusing and seek operations of the pickup 3.

In addition, the RF signal reproducing section 7 is configured to RF amplify the signal provided from the pickup 3 to remove noise and distortion of the signal by the waveform equalization circuit, and to output the waveform after shaping the waveform. (9) is configured to demodulate the data signal provided from the RF signal reproducing unit (7) and correct and output the error, and the system control unit (11) receives various user commands from the outside and corresponds to various circuit units corresponding thereto. It is configured to control the operation of.

In addition, the servo controller 13 receives a predetermined feedback signal provided from the RF signal reproducing unit 7 and outputs a signal corresponding thereto to operate the spindle motor, the actuator and the sled motor provided in the driving unit 5. It is configured to control.

Also, the AV decoder unit 15 is configured to digitally process and decode the audio / video data stream supplied from the data processing unit 9 and output reproduction data.

That is, the servo controller 13 generates kick and brake pulses according to the control signal output from the system controller 11 and picks up the motor by rotating the motor attached to the sled motor of the driver 5. Receives the output signal of the movement distance sensor (3) to detect the movement distance of the pickup (3) and at the same time determine the inversion and stop time of the kick and brake to perform a search operation.

The system control unit 11 simultaneously inputs the pickup from the RF signal reproducing unit 7 when a predetermined track jump command is input from an external input means, that is, data for a target track position to which the pickup 3 is to be moved. Data about the current track position is provided, the number of tracks to be picked up by the pickup 3 is calculated, the kick and brake timings of the sled motor are determined, and the corresponding control signals are output.

In the above-described general sled movement method, a voltage is applied to the sled motor of the driving unit 5 according to the control signal of the servo control unit 13 and the pickup 3 is moved by the force. Adjust the force of the acceleration and deceleration sections on the sled motor to ensure optimum track jump through several tests to ensure that the pickup (3) moves properly.

In the kick / brake method of the sled motor, since acceleration and deceleration are inverted by a constant voltage, the period of rotation position sensor of the first sled motor of acceleration is measured, and when the period greater than this comes out in the deceleration section, the deceleration is stopped and the driving unit 5 of The tracking actuator and the sled motor are actuated to stabilize and terminate the movement of the pickup 3.

In this case, a fatal sled driving error occurs when the rotational position sensor cycle of the sled motor is not normally checked due to the eccentricity.

The sled driving error is decelerated in the state where the frequency of the PS pulse which is the rotation position signal of the sled motor is maximum, that is, the acceleration of the sled motor is maximized, as shown in FIG. As shown in the stabilization section after the brake section of the red (SL) signal, deceleration instability is caused, thereby increasing the time from driving the sled motor to normal locking.

Therefore, in general, a fatal sled driving error occurs when the pickup of the position sensor (PS) rotation period of the sled motor is not normally performed due to the eccentricity when the pickup is driven from the inner circumference to the outer circumference or the outer circumference of the disk. . In this case, when the period of eccentricity becomes long in the period where the signal period of position sensor PS is small, it is regarded as a stop condition, and when the brake pulse is generated, it stops despite the short time of the brake. There was a problem that the time was delayed and the pickup was unstable when the sled on.

In order to solve the problems of the prior art, the present invention accurately recognizes information on the speed of the sled motor and the moving distance of the pickup during track jump and search, and the sampling data of the acceleration section and the deceleration section during the sled driving. By controlling the speed of the sled before the brake section of the sled motor and appropriately decelerating, the pickup stabilization time after the brake section is shortened to provide a pickup movement control apparatus and method that improves the data access time.

In order to achieve the above object, the apparatus of the present invention is a pickup that reads data stored on an optical disk on which predetermined data is recorded and converts the data into an electrical signal, and RF-amplifies the signal provided from the pickup to equalize waveforms of noise and distortion of the signal. An optical disc reproducing system comprising an RF signal reproducing unit for removing a circuit, shaping and outputting a waveform, and a data processing unit for demodulating the data signal provided from the RF signal reproducing unit and correcting and outputting an error. A drive unit including a spindle motor, an actuator, and a sled motor for rotating the disk of the pickup unit according to a control signal of the pickup unit and performing tracking, focusing, and seeking operations of the pickup; A command for a target track position to which the pickup is to be moved from an external input means is received, and data about the current track position of the pickup is received from the RF signal reproducing unit to calculate a distance to which the pickup is to be moved, and according to the calculated movement distance of the pickup. A system controller for controlling the operation of various circuit units; A memory storing an optimum brake control timing according to the target period of the acceleration section of the sled motor, the maximum speed period of the constant speed section, the track jump distance of the pickup, and the driving speed of the sled motor; And receiving a predetermined feedback signal provided from the RF signal reproducing unit and outputting a signal corresponding thereto to control the driving unit, and detecting and counting a predetermined motor rotation position signal from a position sensor provided in the sled motor of the driving unit. Thereafter, the servo control unit may further include controlling a brake timing according to the speed and brake control data of the sled motor set in the memory.

In addition, in order to achieve the above object, the operation method of the present invention comprises the steps of preparing the optimum brake timing and speed control data in the look-up table based on the driving speed of the sled motor and the moving distance of the pickup and setting them in a memory. ; Determining whether a command for moving the pickup to a predetermined address has been input from the external input means after performing the above steps; When the target address data to which the pickup is to be moved is input from the external input means, receiving current address data of the pickup and calculating a distance to which the pickup should be moved; Determining brake control data that is optimal for controlling the speed of the sled motor based on the driving speed of the current sled motor and the moving distance of the pickup based on the calculated movement distance data; After determining the speed control of the sled motor in the step, driving the sled motor with a kick signal of the servo controller and moving the pickup to a predetermined address; Determining whether it is time to operate the brake mode after passing the acceleration section and the constant velocity section of the sled motor while moving the pickup in the step; And controlling the brake operation and the speed of the sled motor according to the speed control data determined above when the time for starting the brake mode is reached.

1 is a block diagram showing a general optical application.

FIG. 2 is a waveform diagram illustrating the sled motor control signal of FIG. 1.

3 is a block diagram illustrating an apparatus for controlling an optical device servo according to an exemplary embodiment of the present invention.

4 is a waveform diagram illustrating a speed control timing diagram of a sled motor by the servo controller of FIG. 3.

5 is a flowchart illustrating an operation process of FIG. 3.

Explanation of symbols on the main parts of the drawings

20: pickup section. 21: disk.

23: pickup. 25: drive part.

30; RF signal regeneration unit. 35: data processing unit.

40: system control unit. 45: memory.

50: servo control unit. 51: PS detection unit.

53: DSP control unit. 55: D / A conversion unit.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

3 is a block diagram showing a servo control apparatus according to an embodiment of the present invention, wherein the pickup section 20, the driver section 25, the RF signal reproducing section 30, the data processing section 35, and the system are shown. And a controller 40, a memory 45, and a servo controller 50.

On the other hand, the pickup section 20 is constituted by a pickup 23 which detects data from the disc 21 on which data is recorded in accordance with a predetermined playback command signal.

In addition, the driving unit 25 is configured to rotate the disk 21 of the pickup unit 20 according to a predetermined control signal and perform tracking, focusing, and seek operations of the pickup 23. It is. That is, the drive unit 25 includes a spindle motor for rotating the disk 21, an actuator for controlling tracking and focusing of the pickup 23, and a pickup 23 at the time of seeking. It consists of a sled motor which moves to a predetermined track on 21 and jumps.

In addition, the RF signal reproducing section 30 is configured to RF amplify the signal provided from the pickup 23 to remove noise and distortion of the signal by the waveform equalization circuit, and to output the waveform after shaping the waveform. 35 is configured to demodulate the data signal provided from the signal reproducing section 30, correct and output an error, and the system control section 40 commands a target address to which the pickup 23 will move from an external input means. Receiving the data and receiving data about the current address of the pickup 23 from the signal reproducing unit 30 to calculate the distance to which the pickup 23 moves, and according to the calculated movement distance of the pickup 23 Configured to control operation.

In addition, the memory 45 is configured to store the optimum brake control timing according to the acceleration period target period and the maximum speed period of the constant speed section of the sled motor, the track jump distance of the pickup, and the driving speed of the sled motor.

In addition, the servo controller 50 receives a predetermined feedback signal provided from the signal reproducing unit 30 and outputs a signal corresponding thereto to control the spindle motor of the driving unit 25, the tracking and focusing actuator, and the sled motor. After detecting and counting a predetermined motor rotation position signal from a position sensor mounted on the sled motor of the driving unit 25, the brake timing is controlled according to the speed and brake control data of the sled motor set in the memory 45. It is configured to.

The servo controller 50 is provided with a PS0 and PS1 signals having different phases from the rotation position sensor PS provided in the sled motor of the driver 25 and counts the period of the input signal with the PS detector 51. And a DSP control unit 53 for outputting a speed control signal of the sled motor using the speed control table set in the memory 45 according to the period of the detected PS0 and PS1 signals, and outputting from the DSP control unit 53. DA conversion unit 55 converts the digital control signal into an analog signal and controls the driving of the sled motor.

That is, when the track jump command for the target track position to which the pickup 23 is to be moved is input from the external input means, the system controller 40 receives the data about the current track position of the pickup from the signal reproducing unit 30 and the pickup is performed. The number of tracks to be moved is calculated, and the servo controller 50 receives target track position data to which the pickup is to be moved from the system controller 40, and the speed set in the memory 45 based on the movement distance of the pickup and the movement speed of the sled motor. After determining the optimum speed control data by referring to the control table, kick and brake pulses are generated by the sled motor to move the pickup to the desired track position.

4 is a waveform diagram illustrating a speed control timing diagram of a sled motor by the servo controller of FIG. 3. FIG. 4A is a waveform diagram illustrating a sled motor control signal SL output from the servo controller. A timing diagram showing the motor rotation position signal PS output from the position sensor of the sled motor.

In FIG. 4A, when a predetermined track position search command is input from an external input means, the servo controller 50 generates a kick signal to drive a sled motor, and the sled motor drives the pickup 23 on a disk. Move to a predetermined track position.

When the kick signal driving the sled motor is applied with a high voltage during the acceleration section of the motor and enters the constant speed section over time, the motor can maintain the same speed even at a low voltage.

As shown in FIG. 4B, the rotational frequency of the rotational position sensor (hall element) included in the sled motor also has a low rotational frequency in the acceleration section and a high frequency in the constant velocity section. In the acceleration section, the acceleration is made at the same speed, and in the deceleration section, the speed is reduced in the state that the speed is considerably slowed down for stable deceleration.

On the other hand, one embodiment of the speed control table of the sled motor set in the memory 45 is as shown in Table 1.

Sampling number data Index Sampling number data Index 001D # 4352-4224 3 kHz 007D # 2304-2177 23 # 4352-4224 2.5 kHz 84 # 2176-2049 002C # 4352-4224 2 kHz 008D # 2048-1921 002C # 4224-4097 2 kHz 97 # 1920-1793 003B # 4096-3969 1.5 kHz 00A2 # 1792-1665 003B # 3968-3841 1.5 kHz 00AF # 1664-1537 004A # 3840-373- 00BE # 1536-1409 004D # 3712-3585 00D0 # 1408-1281 004F # 3584-3457 00E6 # 1280-1153 52 # 3456-3329 101 # 1152-1025 56 # 3328-3201 123 # 1024-897 59 # 3200-3073 150 # 896-769 3.8 ms 005D # 3072-2945 017E # 768-641 4.3 ms 61 # 2944-2817 01BA # 640-513 5.0 ms 66 # 2816-2689 020D # 512-385 5.9 ms 006A # 2688-2561- 287 # 384-257 7.3 ms 70 # 2560-2433 04B3 # 128-1 13.6 ms 76 # 2432-2305 083F # 128-1 23.9 ms

Table 1 forms the sampling periods (1, 2, 3, 4) by the phase difference of 90 ° between the position signals PS0 and PS1 outputted from the position sensor PS of the sled motor provided in the driver 25, The basic sampling is obtained based on the period, and the target period of the acceleration section is set in the initial velocity table as shown in Table 1, which indicates the maximum velocity period to be applied to the constant velocity section, and is determined by the initial sled acceleration value.

FIG. 5 is a flowchart illustrating the operation of FIG. 3, which will be described with reference to FIGS. 3 and 4.

First, an optimal brake timing and speed control are prepared as a look-up table based on the driving speed of the sled motor and the moving distance of the pickup, and preset in the memory 45 (S1).

After performing step S1, the system controller 40 determines whether or not a command for moving the pickup 23 to a predetermined address is input from an external input means (S2).

When the target address data to which the pickup 23 is to be moved is input from the external input means, the system controller 40 receives the current address data of the pickup from the signal reproducing unit 30 and the pickup 23 is to be moved. A step of calculating the distance is performed (S3).

In addition, the servo controller 50 receives the movement distance data calculated above from the system controller 40 and based on the driving speed of the current sled motor set in the memory 45 and the movement distance of the pickup 23. In operation S4, the brake control data is determined to be optimal for controlling the speed of the sled motor.

After determining the speed control of the sled motor in the step S4, driving the sled motor with the kick signal of the servo controller 50 and moving the pickup 23 to a predetermined address is performed (S5).

While moving the pickup 23 in step S5, the servo controller 50 determines whether it is time to operate the brake mode after passing through the acceleration section and the constant speed section of the sled motor (S6). .

When it is time to start the brake mode in step S6, the servo controller 50 controls the brake timing and operation of the sled motor according to the speed control data determined above (S7).

Therefore, as described above, in the present invention, the stabilization time of the pickup is shortened by controlling the driving speed of the sled motor with reference to the optimum data set according to the distance and the driving speed at which the pickup should move during the disc search. There is an effect that the access time is improved and pickup errors in data detection are reduced.

Claims (4)

A pickup that reads data stored on an optical disk on which predetermined data is recorded and converts the data into an electrical signal, and amplifies the signal provided from the pickup to remove noise and distortion of the signal by a waveform equalization circuit, and outputs the waveform after shaping the waveform. An optical disc reproducing system comprising: an RF signal reproducing section; and a data processing section for demodulating data signals provided from the RF signal reproducing section, correcting errors, and outputting the errors A drive unit including a spindle motor, an actuator, and a sled motor which rotate the disk of the pickup unit according to a predetermined control signal and perform tracking, focusing, and seeking operations of the pickup; A command for the target track position to which the pickup is to be moved is input from an external input unit, and data for the current address of the pickup is received from the RF signal reproducing unit to calculate the distance to which the pickup is to move, and according to the calculated movement distance of the pickup, A system control unit controlling an operation of the circuit unit; A memory storing brake control timings optimized based on a target period of the acceleration section of the sled motor and a maximum speed period of the constant speed section, a track jump distance of the pickup, and a driving speed of the sled motor; And receiving a predetermined feedback signal provided from the RF signal reproducing unit and outputting a signal corresponding thereto to control the driving unit, and detecting and counting a predetermined motor rotation position signal from a position sensor provided in the sled motor of the driving unit. And a servo controller for controlling the brake timing according to the speed and brake control data of the sled motor set in the memory. According to claim 1, wherein the servo control unit, PS detection unit for receiving the first and second position signals of different phases from the rotational position sensor provided in the sled motor of the drive unit and counting the period of the input signal, wherein A DSP control unit for outputting a speed control signal of the sled motor using a speed control table set in a memory according to the detected first and second position signal cycles, and converting a digital control signal output from the DSP control unit into an analog signal And a DA converter configured to control driving of the sled motor. The pickup movement control apparatus according to claim 1, wherein the servo control unit decelerates and controls the driving speed of the sled motor to a predetermined level before the brake section in order to stably decelerate the sled motor of the driving unit. Preparing optimum brake timing and speed control data as a look-up table based on the driving speed of the sled motor and the moving distance of the pickup, and setting them in a memory; Determining whether a command for moving the pickup to a predetermined address has been input from the external input means after performing the above steps; When the target address data to which the pickup is to be moved is input from the external input means, receiving current address data of the pickup and calculating a distance to which the pickup should be moved; Determining brake control data that is optimal for controlling the speed of the sled motor based on the driving speed of the current sled motor and the moving distance of the pickup based on the calculated movement distance data; After determining the speed control of the sled motor in the step, driving the sled motor with a kick signal of the servo controller and moving the pickup to a predetermined address; Determining whether it is time to operate the brake mode after passing the acceleration section and the constant velocity section of the sled motor while moving the pickup in the step; And controlling the brake operation and the speed of the sled motor according to the speed control data determined in the step, when it is time to start the brake mode.

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