Methods and devices for compensating for off-track motion
In certain embodiments, a method includes sensing a mode of a motor-base assembly's response to vibration. Based on the sensed response, the method includes adjusting a head-suspension assembly to compensate for off-track motion caused by the vibration. In certain embodiments, an apparatus includes a sensor positioned on a basedeck such that the sensor senses a mode of the motor-base assembly's response to linear vibration.
1. A method comprising:
sensing a motor-base assembly's structural response to vibration, the structural response including deformation of the motor-base assembly in response to the vibration; and
based on the sensed structural response, adjusting a head-suspension assembly to compensate for off-track motion caused by the vibration,
wherein the motor-base assembly includes a basedeck and motor.
2. The method of claim 1 , wherein a sensor senses the structural response and the sensor is positioned on the basedeck of the motor-base assembly.
3. The method of claim 2 , wherein the sensor is one of an accelerometer, strain gauge, or piezo-electric sensor.
4. The method of claim 1 , wherein the vibration is linear vibration.
5. The method of claim 2 , further comprising:
sensing a first mode of the motor-base assembly's structural response to vibration using a first sensor; and
sensing a second mode of the motor-base assembly's structural response to vibration using a second sensor.
6. The method of claim 5 , wherein each sensor senses a single dimension.
7. The method of claim 1 , further comprising:
sensing a first dimension of a mode of the structural response with a first sensor; and
sensing a second dimension of the mode with a second sensor.
8. The method of claim 7 , wherein the mode is a mode excited by seek energy of a head-suspension assembly moving from one track to another.
9. The method of claim 2 , wherein the sensor is positioned on a motor cup portion of the basedeck.
10. The method of claim 2 , wherein the sensor is positioned on the top of the basedeck.
11. An apparatus comprising:
a sensor positioned on a basedeck such that the sensor senses a motor-base assembly's deformation in response to linear vibration; and
a controller that uses the sensed deformation to correct off-track motion of a read/write head.
12. The apparatus of claim 11 , wherein the sensor is positioned on a motor cup portion of the basedeck.
13. The apparatus of claim 12 , further comprising:
a second sensor positioned on the basedeck such that the second sensor senses a second mode of the motor-base assembly's response to linear vibration.
14. The apparatus of claim 13 , wherein each sensor senses a single dimension of the motor-base assembly's response to linear vibration.
15. A system comprising:
a controller that responds to a position error signal and a sensing signal representative of a sensed mode of vibration of a motor-base assembly's structural response to linear vibration, the motor-base assembly including a basedeck and motor,
wherein the controller adjusts a position of a read/write head in response to the position error signal and sensing signal.
16. The system of claim 15 , further comprising multiple sensors, each sensor sensing a single dimension.
17. The apparatus of claim 16 , wherein the multiple sensors are positioned on the basedeck of the motor-base assembly.
18. The system of claim 17 , wherein the multiple sensors are positioned on a motor cup portion of the basedeck of the motor-base assembly.