| 摘要 |
PROBLEM TO BE SOLVED: To provide a free fall detection method and a free fall detector capable of detecting only the true free falls and prevent malfunctions of a device. SOLUTION: The free fall detecting method includes: a step of detecting an acceleration of the device; a step of integrating a detected acceleration to time; a step of determining whether the detected acceleration is periodic; a step of comparing an integrated value with a first critical value, which becomes the criterion for determination for free fall, to determine whether it is a free fall, when the detected acceleration is aperiodic; and a step of comparing the integrated value with a second critical value, to determine whether it is a free fall, when the detected acceleration is periodic. The second critical value is different from the first critical value. Free-fall malfunctions of the device can be prevented, to reduce unnecessary operations of a hard disk drive, by determining whether the detected acceleration is periodic and detecting only the true free falls. COPYRIGHT: (C)2009,JPO&INPIT |
