Relation of rotational vibration stimuli to performance of a hard disc drive

A method for predicting performance of a disc drive of a drive species mounted in a mechanical mounting environment, the predicted performance of the disc drive based on a rotational vibration index derived from a measurement of an induced rotational vibration stimulus of the mechanical mounting environment by steps comprising:

• (a) providing the disc drive selected from the drive species, the disc drive having a pair of attached accelerometers for capturing and reporting a rotational vibration experienced by the disc drive mounted in the mechanical mounting environment;
• (b) supplying a test system for measuring the rotational vibration experienced by the disc drive mounted in the mechanical mounting environment;
• (c) calibrating the test system to assure substantial accuracy of the measurement made by the pair of accelerometers measuring the induced rotational vibration stimulus applied to the mechanical mounting environment;
• (d) mounting the disc drive with attached accelerometers within the mechanical mounting environment, defining and executing a series of seek patterns to impart the induced rotational vibration stimulus to the mechanical mounting environment while acquiring, analyzing and saving the measurement made by the pair of accelerometers measuring the induced rotational vibration stimulus of the mechanical mounting environment;
• (e) providing a rotational vibration index function for use in determining a rotational vibration index for the mechanical mounting environment, and providing a rotational vibration index for the drive species for use with the rotational vibration index function;
• and
• (f) computing a rotational vibration index for the mechanical mounting environment using the rotational vibration index function applied to the saved measurement taken by the pair of accelerometers of the induced rotational vibration stimulus of the mechanical mounting environment.

A test system for predicting the performance of a disc drive of a drive species mounted in a mechanical mounting environment comprising;

• a pair of accelerometers attached to the disc drive for measuring a response of the disc drive to a rotational vibration stimuli imparted on the mechanical mounting environment;
• a computer with a data acquisition card communicating with the pair of accelerometers, the data acquisition card for acquiring and analyzing the response of the disc drive to the rotational vibration stimuli imparted on the mechanical mounting environment as measured by the pair of accelerometers;
• a storage device communicating with the computer for saving the measurements made by the pair of accelerometers measuring the response of the disc drive to the rotational vibration stimuli imparted on the mechanical mounting environment;
• and
• software incorporating a rotational vibration index function programmed into the computer and communicating with the data acquisition card to compute a rotational vibration index for the mechanical mounting environment by steps for computing the rotational vibration index for the mechanical mounting environment.