GENERATING A VIBRATION PROFILE FOR A ROTATING COOLING DEVICE IN A COMPUTER SYSTEM

• US 20100217543A1
• Filed: 02/23/2009
• Published: 08/26/2010
• Est. Priority Date: 02/23/2009
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Urmanov, Aleksey M., Bougaev, Anton A., McElfresh, David K.
• Granted Patent: US 7,920,974 B2
• Time in Patent Office: Days
• US Class Current: 702/56
• CPC Class Codes: G01M 7/00 Vibration-testing of structures; Shock-testing of structures G01M9/00 takes precedence
• CPC Class Codes: G01M 7/025 Measuring arrangements

Abstract

One embodiment of the present invention provides a system that generates a vibration profile for a rotational device in a computer system. During operation, the system sequentially sweeps a rotation speed of a rotational device over a range of rotation speeds. While driving the rotational device at each rotation speed, the system collects a time-domain vibration signal produced by the rotational device and subsequently computes a frequency spectrum of the time-domain vibration signal. In this way, the system generates a set of frequency spectra associated with the range of rotation speeds. Next, the system combines the set of frequency spectra to generate a composite vibration profile for the rotational device.

Claims

1. A method for a generating a vibration profile for a rotational device in a computer system, the method comprising:

sequentially sweeping a rotation speed of a rotational device over a range of rotation speeds, and, while driving the rotational device at each rotation speed,

collecting a time-domain vibration signal produced by the rotational device; and

computing a frequency spectrum of the time-domain vibration signal, thereby generating a set of frequency spectra associated with the range of rotation speeds;

combining the set of frequency spectra to generate a composite vibration profile for the rotational device;

identifying at least one structural resonance of the computer system; and

modifying the composite vibration profile for the rotational device to mitigate the effect of the at least one structural resonance of the computer system.

2. The method of claim 1, wherein collecting the time-domain vibration signal involves using a vibration sensor coupled to the rotational device.

3. The method of claim 2, wherein the vibration sensor is an accelerometer.

4. The method of claim 1, wherein the rotational device is a rotational cooling device, which can include a cooling fan, or an air mover.

5. The method of claim 1,

wherein each frequency spectrum comprises a set of values corresponding to a set of frequency bins;

and

wherein combining the set of frequency spectra to generate the composite vibration profile involves, at each frequency bin, selecting the maximum amplitude among the set of amplitudes for the set of frequency spectra to represent the amplitude at the frequency bin for the composite vibration profile.

6. The method of claim 5, wherein the composite vibration profile represents worst-case vibration levels for the set of frequency bins.

7. The method of claim 1, wherein the method further comprises identifying a set of resonant frequencies within the composite vibration profile.

8. The method of claim 1, wherein the rotational device is mechanically affixed to the chassis of the computer system.

9. A computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for generating a vibration profile for a rotational device in a computer system, the method comprising:

sequentially sweeping a rotation speed of a rotational device over a range of rotation speeds, and, while driving the rotational device at each rotation speed,

collecting a time-domain vibration signal produced by the rotational device; and

computing a frequency spectrum of the time-domain vibration signal, thereby generating a set of frequency spectra associated with the range of rotation speeds;

combining the set of frequency spectra to generate a composite vibration profile for the rotational device;

identifying at least one structural resonance of the computer system; and

modifying the composite vibration profile for the rotational device to mitigate the effect of the at least one structural resonance of the computer system.

10. The computer-readable storage medium of claim 9, wherein collecting the time-domain vibration signal involves using a vibration sensor coupled to the rotational device.

11. The computer-readable storage medium of claim 10, wherein the vibration sensor is an accelerometer.

12. The computer-readable storage medium of claim 9, wherein the rotational device is a rotational cooling device, which can include a cooling fan, or an air mover.

13. The computer-readable storage medium of claim 9,

wherein each frequency spectrum comprises a set of values corresponding to a set of frequency bins;

and

wherein combining the set of frequency spectra to generate the composite vibration profile involves, at each frequency bin, selecting the maximum amplitude among the set of amplitudes for the set of frequency spectra to represent the amplitude at the frequency bin for the composite vibration profile.

14. The computer-readable storage medium of claim 13, wherein the composite vibration profile represents worst-case vibration levels for the set of frequency bins.

15. The computer-readable storage medium of claim 9, wherein the method further comprises identifying a set of resonant frequencies within the composite vibration profile.

16. The computer-readable storage medium of claim 9, wherein the rotational device is mechanically affixed to the chassis of the computer system.

17. An apparatus that generates a vibration profile for a rotational device in a computer system, comprising:

a speed-sweep mechanism configured to sequentially sweep a rotation speed of a rotational device over a range of rotation speeds;

a data-collection mechanism configured to collect a time-domain vibration signal produced by the rotational device while the rotational device is rotating at each rotation speed;

a computing mechanism configured to compute a frequency spectrum of the time-domain vibration signal associated with each rotation speed, thereby generating a set of frequency spectra associated with the range of rotation speeds, wherein the computing mechanism is further configured to combine the set of frequency spectra to generate a composite vibration profile for the rotational device;

a resonance-identification mechanism configured to identifying at least one structural resonance of the computer system; and

a remediation mechanism configured to modify the composite vibration profile for the rotational device to mitigate the effect of the at least one structural resonance of the computer system.

18. The apparatus of claim 17, wherein the data-collection mechanism includes a vibration sensor coupled to the rotational device to collect the time-domain vibration signal.

19. The apparatus of claim 18, wherein the vibration sensor is an accelerometer.

20. The apparatus of claim 17, wherein the rotational device is a rotational cooling device, which can include a cooling fan, or an air mover.