Object positioning system

Claim 2

A positioning system for controlling an controlled object which is to be moved quickly in a high speed moving mode and positioned finely in a fine moving mode, said system comprising: position detecting means for detecting an absolute position of said controlled object, and producing an absolute position data; seek control means for comparing the absolute position data with a predetermined goal data to produce a position compensation data representing a difference between the absolute position data and the goal data, said seek control means outputting a seek command when the position compensation data is larger than a predetermined value; velocity sense means for detecting a kinetic velocity of said controlled object and decreasing its gain in response to the seek command; velocity numerating means for numerating an output of said velocity sense means to obtain a velocity data; addition means for adding the velocity data to the position compensation data from said seek control means; operation means for numerically operating an output of said addition means to obtain a position control data, and multiplying the position control data by a predetermined coefficient, the predetermined coefficient being increased in response to the seek command; voltage conversion means for converting an output data from said operation means into a voltage signal; and drive means for driving said controlled object according to the voltage signal.

Claim 3

In an optical disc player which reproduces information recorded in tracks on a recording disc by using an optical head which focuses a light beam to form a light spot on a track on the recording disc and detects a reflected beam from the recording disc, a positioning system for positioning the optical head comprising: tracking error detection means for detecting a tracking error from the reflected beam; tracking control means for controlling the optical head to allow the light spot to follow the track according to the tracking error; carriage means for traversing the optical head across said tracks; position detecting means for detecting an absolute position of said carriage means, and producing an absolute position data; seek control means for comparing the absolute position data with a predetermined goal data representing a desired track and calculating a position compensation data representing a difference between the absolute position data and the goal data, said seek control means outputing an address seeking command when the position compensation data is larger than a predetermined value; selection means which normally selects a tracking operation data from said tracking control means, and is responsive to the address seeking command to select the position compensation data; velocity sense means for detecting a kinetic velocity of said carriage means and decreasing its gain in response to the address seeking command; velocity numerating means for numerating an output of said velocity sense means and to obtain a velocity data; addition means for adding the velocity data to an output data from said selection means; operation means for numerically operating an output data from said additional means to obtain a position control data; variable coefficient means for multiplying the position control data by a predetermined coefficient, the predetermined coefficient being increased in response to the address seeking command; voltage conversion means for converting an output data from said variable coefficient menas into a voltage signal; and drive means for driving said carriage means according to the voltage signal.

Claim 4

In an optical disc player which reproduces information recorded in tracks on a recording disc by using an optical head which focuses a light beam to form a light spot on a track on the recording disc and detects a reflected beam from the recording disc, a positioning system for positioning the optical head comprising: tracking error detection means for detecting a tracking error from the reflected beam; tracking control means for controlling the optical head to allow the light spot to follow the track according to the tracking error; carriage means for traversing the optical head across said tracks; position detecting means for detecting an absolute position of said carriage means, and producing an absolute position data; seek control means for comparing the absolute position data with a predetermined goal data representing a desired track and calculating a position compensation data representing a difference between the absolute position data and the goal data, said seek control means outputing an address seeking command when the position compensation data is larger than a predetermined value; selection means which normally selects a tracking operation data from said tracking control means, and is responsive to the address seeking command to select the position compensation data; velocity sense means for detecting a kinetic velocity of said carriage means and decreasing its gain in response to the address seeking command; velocity numerating means for numerating an output of said velocity sense means and to obtain a velocity data; addition means for adding the velocity data to an output data from said selection means; operation means for numerically operating an output data from said additional means to obtain a position control data; variable coefficient means for multiplying the position control data by a predetermined coefficient, the predetermined coefficient being increased in response to the address seeking command; voltage conversion means for converting an output data from said variable coefficient menas into a voltage signal; and drive means for driving said carriage means according to the voltage signal.

Claim 5

In an optical disc player which reprodices information recorded in tracks on a recording disc by using an optical head which focuses a light beam to form a light spot on a track and detects a reflected light beam from the recording disc, and operates in one of an address seeking mode for moving the optical head from one track to another and a track following mode for allowing the light spot to trace a track, a positioning system for positioning the optical head, comprising: carriage means for traversing the optical head across the tracks, a velocity feedback loop for controlling a velocity of said carriage means, said velocity feedback loop having a velocity detecting means which normally detects a velocity of said carriage means in a high resolution; and control means for producing an address seeking command only in said address seeking mode, wherein said velocity detecting means is responsive to said address seeking command for decreasing its gain so as to detect a velocity of said carriage means in a wide velocity range in said address seeking mode.

Claim 6

In an optical disc player which reprodices information recorded in tracks on a recording disc by using an optical head which focuses a light beam to form a light spot on a track and detects a reflected light beam from the recording disc, and operates in one of an address seeking mode for moving the optical head from one track to another and a track following mode for allowing the light spot to trace a track, a positioning system for positioning the optical head, comprising: carriage means for traversing the optical head across the tracks, a velocity feedback loop for controlling a velocity of said carriage means, said velocity feedback loop having a velocity detecting means which normally detects a velocity of said carriage means in a high resolution; and control means for producing an address seeking command only in said address seeking mode, wherein said velocity detecting means is responsive to said address seeking command for decreasing its gain so as to detect a velocity of said carriage means in a wide velocity range in said address seeking mode.

Claim 7

The positioning system according to claim 3, wherein said velocity feedback loop has a means which is responsive to said address seeking command for keeping constant a total gain of said velocity feedback loop.

Claim 8

The positioning system according to claim 3, wherein said control means comprises a position detecting means for detecting an absolute position of said carriage means, and a seek control means for comparing the absolute position detected by said position detecting means with a predetermined goal position and outputting said address seeking command when a difference between the absolute position and the goal position is larger than a predetermined distance.