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US5206570A Expired / Lapsed US ⏱️ 0.0 years remaining

Actuator servo compensation method

Assignee: Maxtor Corp
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Filing: 1991-03-19
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Granted: 1993-04-27
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Expires: 2011-03-19
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Abstract

Abstract An actuator control loop for controlling head position in a rotating media data storage system. The invention applies the compensation zero to the PES prior to summing it with the integrator. This scheme reduces transients caused by the integrator initialization step because the zero does not "see" the integrator initialization step. Transients that can result from coupling the integrator initialization to the zero can cause overshoot and ringing in the actuator, increasing settling time and reducing system performance. The present invention also provides a first sample velocity compensation scheme that removes the velocity correction factor from the PES signal in the first sample after a seek. This significantly reduces settling time and improves system performance. In one embodiment, the microprocessor of the present invention calculates a velocity compensation factor based on the PES signal. This signal is then superimposed on the integrator output. In another embodiment, the zero is moved during the first sample after a seek, so that no velocity correction is undertaken. In subsequent sample periods, the zero is returned to its desired frequency.

Inventors

  • 👤 Jim Hargarten
  • 👤 Gary Counts
  • 👤 Scott Chase

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 18:03
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/54; G11B5/55; G11B5/5521; G11B5/5526; G11B5/553; G11B5/5547

Claims Analysis

Total Claims: 29
Claim 1
Independent Claim 143 words
A circuit for providing a position compensation signal comprising: receiving means for receiving an error signal and for generating a position error signal (PES) having a normal component and a quadrature component; integrating means coupled to said receiving means for integrating said normal component and providing a first output signal; compensating means coupled to said receiving means for compensating said normal component and providing a second output signal; first summing means coupled to said integrating means and said compensating means for summing said first and second output signals and providing a third output signal; filter means coupled to said first summing means for providing a fourth output signal; amplifying means coupled to said filter means for generating a fifth output signal; actuator control means coupled to said amplifying means and to said receiving means, said actuator control means for providing said error signal.
Claim 2
Dependent Claim 143 words
A circuit for providing a position compensation signal comprising: receiving means for receiving an error signal and for generating a position error signal (PES) having a normal component and a quadrature component; integrating means coupled to said receiving means for integrating said normal component and providing a first output signal; compensating means coupled to said receiving means for compensating said normal component and providing a second output signal; first summing means coupled to said integrating means and said compensating means for summing said first and second output signals and providing a third output signal; filter means coupled to said first summing means for providing a fourth output signal; amplifying means coupled to said filter means for generating a fifth output signal; actuator control means coupled to said amplifying means and to said receiving means, said actuator control means for providing said error signal.
Claim 3
Dependent Claim 15 words
The circuit of claim 1 wherein said integrating means is implemented in a processing means.
Claim 4
Dependent Claim 12 words
The circuit of claim 2 wherein said processing means comprises a microprocessor.
Claim 5
Dependent Claim 14 words
The circuit of claim 1 wherein said filter means comprises a low pass filter.
Claim 6
Dependent Claim 29 words
The circuit of claim 1 further including a switching means disposed between said receiving means and said compensating means for selectively providing said normal component to said compensating means.
Claim 7
Dependent Claim 104 words
The circuit of claim 1 wherein said compensating means, said first summing means and said filter means are comprised of: a first capacitor and a first resistor coupled in parallel to said normal component and to a first node; a second resistor coupled to said first output signal and to said first node; a third resistor coupled to said first node and to an input of an amplifier, said amplifier providing said fourth output signal; a second capacitor coupled to said fourth output signal and said input of said amplifier; a fourth resistor coupled to said fourth output signal and to said first node.
Claim 8
Dependent Claim 74 words
An actuator control loop comprising: integrating means coupled to a position error signal (PES) and providing a first output signal compensating means coupled to said PES for compensating said PES and providing a second output signal; summing means coupled to said integrating means and said compensating means for summing said first and second output signals and providing a third output signal; filter means coupled to said summing means for providing a fourth output signal.
Claim 9
Dependent Claim 74 words
An actuator control loop comprising: integrating means coupled to a position error signal (PES) and providing a first output signal compensating means coupled to said PES for compensating said PES and providing a second output signal; summing means coupled to said integrating means and said compensating means for summing said first and second output signals and providing a third output signal; filter means coupled to said summing means for providing a fourth output signal.
Claim 10
Dependent Claim 17 words
The actuator control loop of claim 7 wherein said integrating means is implemented in a processing means.
Claim 11
Dependent Claim 14 words
The actuator control loop of claim 8 wherein said processing means comprises a microprocessor.
Claim 12
Dependent Claim 16 words
The actuator control loop of claim 7 wherein said filter means comprises a low pass filter.
Claim 13
Dependent Claim 29 words
The actuator control loop of claim 7 further including a switching means disposed between said PES and said compensating means for selectively providing said PES to said compensating means.
Claim 14
Dependent Claim 106 words
The actuator control loop of claim 7 wherein said compensating means, said first summing means and said filter means are comprised of: a first capacitor and a first resistor coupled in parallel to said normal component and to a first node; a second resistor coupled to said first output signal and to said first node; a third resistor coupled to said first node and to an input of an amplifier, said amplifier providing said fourth output signal; a second capacitor coupled to said fourth output signal and said input of said amplifier; a fourth resistor coupled to said fourth output signal and to said first node.
Claim 15
Independent Claim 105 words
A method of providing an actuator control signal comprising the steps of: generating a position error signal (PES) and separating a normal component from said PES; providing said normal component to an integrating means to generate a first output signal; providing said normal component to a compensating means to generate a second output signal; summing said first and second output signals to generate a third output signal; filtering said third output signal to generate a fourth output signal; amplifying said fourth output signal to generate a fifth output signal; providing said fifth output signal to an actuator control block to generate said actuator control signal.
Claim 16
Independent Claim 105 words
A method of providing an actuator control signal comprising the steps of: generating a position error signal (PES) and separating a normal component from said PES; providing said normal component to an integrating means to generate a first output signal; providing said normal component to a compensating means to generate a second output signal; summing said first and second output signals to generate a third output signal; filtering said third output signal to generate a fourth output signal; amplifying said fourth output signal to generate a fifth output signal; providing said fifth output signal to an actuator control block to generate said actuator control signal.
Claim 17
Dependent Claim 18 words
The method of claim 13 wherein said step of integrating said normal component is performed in a microprocessor.
Claim 18
Dependent Claim 21 words
The method of claim 13 wherein said step of filtering said third output signal is performed using a low pass filter.
Claim 19
Dependent Claim 95 words
An actuator control loop comprising: a first capacitor and a first resistor coupled in parallel to a normal component of a position error signal (PES) and to a first node; a second resistor coupled to a first input signal and to said first node; a third resistor coupled to said first node and to an input of an amplifier, said amplifier providing a second output signal; a second capacitor coupled to said second output signal and said input of said amplifier; a fourth resistor coupled to said second output signal and to said first node.
Claim 20
Dependent Claim 95 words
An actuator control loop comprising: a first capacitor and a first resistor coupled in parallel to a normal component of a position error signal (PES) and to a first node; a second resistor coupled to a first input signal and to said first node; a third resistor coupled to said first node and to an input of an amplifier, said amplifier providing a second output signal; a second capacitor coupled to said second output signal and said input of said amplifier; a fourth resistor coupled to said second output signal and to said first node.
Claim 21
Independent Claim 70 words
A method for providing an actuator control signal comprising the steps of: receiving a correction signal having a position error component and a velocity error component; in a first sample period, determining said velocity error component; generating a compensation signal to reduce the effects of said velocity error component; providing said compensation signal and said correction signal to an actuator control loop such that only said position error is corrected.
Claim 22
Independent Claim 70 words
A method for providing an actuator control signal comprising the steps of: receiving a correction signal having a position error component and a velocity error component; in a first sample period, determining said velocity error component; generating a compensation signal to reduce the effects of said velocity error component; providing said compensation signal and said correction signal to an actuator control loop such that only said position error is corrected.
Claim 23
Dependent Claim 28 words
The method of claim 17 further including the step of providing only said correction signal to said actuator control loop in sample periods after said first sample period.
Claim 24
Dependent Claim 47 words
The method of claim 17 wherein said compensation signal is generated by: ##EQU8## where X IC is the head initial position, K DEMOD is the gain of the PES in volts/track, K DA is the DAC gain and A I and A p are DC gain factors.
Claim 25
Dependent Claim 47 words
The method of claim 17 wherein said compensation signal is generated by: ##EQU9## where X IC is the head initial position, K DEMOD is the gain of the PES in volts/track, K DA is the DAC gain and A I and A p are DC gain factors.
Claim 26
Dependent Claim 18 words
The method of claim 17 wherein said step of generating said compensation signal is accomplished in a microprocessor.
Claim 27
Dependent Claim 120 words
An actuator control loop comprising: a first capacitor coupled to a normal component of a position error signal (PES) and to a first node; switch means having a first terminal coupled to said normal component of said PES; a first resistor coupled to a second terminal of said switch means and to said first node; a second resistor coupled to a first input signal and to said first node; a third resistor coupled to said first node and to an input of an amplifier, said amplifier providing a second output signal; a second capacitor coupled to said second output signal and said input of said amplifier; a fourth resistor coupled to said second output signal and to said first node.
Claim 28
Dependent Claim 120 words
An actuator control loop comprising: a first capacitor coupled to a normal component of a position error signal (PES) and to a first node; switch means having a first terminal coupled to said normal component of said PES; a first resistor coupled to a second terminal of said switch means and to said first node; a second resistor coupled to a first input signal and to said first node; a third resistor coupled to said first node and to an input of an amplifier, said amplifier providing a second output signal; a second capacitor coupled to said second output signal and said input of said amplifier; a fourth resistor coupled to said second output signal and to said first node.
Claim 29
Dependent Claim 24 words
The actuator control loop of claim 22 wherein said switch means is open during a first sample period and closed during subsequent sample periods.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-04-26 1996-10-26 1997-04-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-04-26 2000-10-26 2001-04-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-04-26 2004-10-26 2005-04-27 $7700.00 Window Closed / Lapsed

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