Multirate digital control system for use with a system having a linear
transfer function, such as a head positioning system in a magnetic disc
drive
    1.
    发明授权
    Multirate digital control system for use with a system having a linear transfer function, such as a head positioning system in a magnetic disc drive 失效
    用于具有线性传递功能的系统的多速率数字控制系统,例如磁盘驱动器中的头部定位系统

    公开(公告)号:US5721648A

    公开(公告)日:1998-02-24

    申请号:US589791

    申请日:1996-01-22

    摘要: A multirate sampled closed-loop digital servo system controls read/write head positioning in a magnetic disc storage device. Using a multirate estimator, positional data embedded in the storage medium is sampled once per sector, and inter-sector positional information is predicted. At least two control signals are provided per sample. The control signals are outputted at a multiple of the measurement sample rate, e.g., twice the sample rate. The estimator estimates head position and velocity, system and DC bias, and accounts for estimator calculation time delay, in the system and in the control updates. Estimated states are based on the measurement, control value, last control value, and last estimated states. Input information used by the estimator includes the digitized sampled position error signal (PES), the Gray code value, the present digital control value, and the last digital control value. At every sample, the present invention calculates the control values based upon estimated read/write head position and velocity, and the absolute position of the target track. Both present and last control values are used for the estimator to compensate for computational delay and for additional system phase lags. To minimize computational delay, the algorithm implementing the estimator and controller requires but one multiplication and one addition are necessary to calculate the control value. Once the heads are moved close to the desired target tracks, the servo operates closed-loop in track-follow mode.

    摘要翻译: 多速率采样闭环数字伺服系统控制磁盘存储设备中的读/写头定位。 使用多速率估计器,嵌入在存储介质中的位置数据每扇区采样一次,并且预测扇区间位置信息。 每个样品至少提供两个控制信号。 控制信号以测量采样率的倍数输出,例如采样速率的两倍。 估计器估计头部位置和速度,系统和直流偏差,并考虑到系统和控制更新中的估计器计算时间延迟。 估计状态基于测量值,控制值,最后控制值和最后估计状态。 由估计器使用的输入信息包括数字化采样位置误差信号(PES),格雷码值,当前数字控制值和最后数字控制值。 在每个样本中,本发明基于估计的读/写头位置和速度以及目标轨道的绝对位置来计算控制值。 当前和最后一个控制值都用于估计器以补偿计算延迟和额外的系统相位滞后。 为了最小化计算延迟,实现估计器和控制器的算法需要一个乘法和一个相加来计算控制值。 一旦磁头移动靠近所需的目标磁道,伺服器在跟踪跟踪模式下操作闭环。

    Extended position error signal linearization and normalization
    2.
    发明授权
    Extended position error signal linearization and normalization 失效
    扩展位置误差信号线性化和归一化

    公开(公告)号:US06188539B1

    公开(公告)日:2001-02-13

    申请号:US09115574

    申请日:1998-07-14

    IPC分类号: G11B5596

    摘要: A method of producing a position error signal includes storing a normal position error value generated from a normal servo field and a quadrature position error value generated from a quadrature servo field, where the normal servo field is ninety degrees out of phase from the quadrature servo field. A position error numerator is created by arithmetically combining the normal position error value and the quadrature position error value. A position error denominator is created based on the normal position error value and the quadrature position error value. The position error signal is produced by dividing the position error numerator by the position error denominator.

    摘要翻译: 一种产生位置误差信号的方法包括存储从正常伺服场产生的正常位置误差值和从正交伺服场产生的正交位置误差值,其中正常伺服场从正交伺服场中相差九十度 。 通过将正常位置误差值和正交位置误差值进行算术组合来创建位置误差分子。 基于正常位置误差值和正交位置误差值创建位置误差分母。 位置误差信号是通过将位置误差分子除以位置误差分母而产生的。