CN105304098A - 基于虚拟伺服磁道伺服控制磁头的数据存储设备 - Google Patents
基于虚拟伺服磁道伺服控制磁头的数据存储设备 Download PDFInfo
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Abstract
本发明涉及基于虚拟伺服磁道伺服控制磁头的数据存储设备。公开一种数据存储设备，其包括第一磁盘表面和第一磁盘表面上方致动的第一磁头，所述第一磁盘表面包括由伺服扇区限定且以第一径向密度记录的伺服磁道。第一磁盘表面上的伺服扇区被读取以生成第一物理位置测量值，该第一物理位置测量值被转换为对应于不同于第一径向密度的伺服磁道的标称径向密度的第一虚拟位置测量值。基于第一虚拟位置测量值在第一磁盘表面上方伺服控制第一磁头。
Description
背景技术
数据存储设备(诸如磁盘驱动器)包括磁盘和连接到致动器臂的远端的磁头，致动器臂通过音圈电机(VCM)围绕枢轴旋转以将磁头径向定位在磁盘上方。磁盘包括多个径向间隔的同心磁道，其用于记录用户数据扇区和伺服扇区。伺服扇区包括磁头定位信息(例如，磁道地址)，其由磁头读取并且由伺服控制系统处理以在逐磁道搜寻时控制致动器臂。
图1示出现有技术的磁盘格式2，其包括由围绕每个伺服磁道的圆周记录的伺服扇区60-6N限定的若干伺服磁盘4。每个伺服扇区6i包括用于存储周期图案的前导码8和用于存储特定图案的同步标记10，其中周期图案允许适当增益调整和读信号的时序同步，特定图案用于符号同步到伺服数据字段12。伺服数据字段12存储粗磁头定位信息(诸如伺服磁道地址)，其用于在寻道操作期间将磁头定位在目标数据磁道上方。每个伺服扇区6i进一步包括伺服脉冲14(例如，N和Q伺服脉冲)组，它们使用相对于彼此以及相对于伺服磁道中心线的预定相位被记录。基于相位的伺服脉冲14提供精细磁头位置信息，所述精细磁头定位信息用于中心线跟踪并在写/读操作期间访问数据磁道。位置误差信号(PES)通过读取伺服数据12和伺服脉冲14产生，其中PES表示测量的磁头相对于目标伺服磁道的中心线的位置。伺服控制器处理PES以生成应用到磁头致动器(例如，音圈电机)的控制信号，以便沿减小PES的方向在磁盘上方径向致动磁头。
附图说明
图1示出包括伺服扇区限定的多个伺服磁道的现有技术磁盘格式。
图2A示出根据一个实施例的磁盘驱动器形式的数据存储设备，其中磁盘驱动器包括在磁盘表面上方被致动的磁头。
图2B示出根据一个实施例的磁盘驱动器形式的数据存储设备，其中磁盘驱动器包括在多个磁盘表面上方被致动的磁头。
图2C是根据一个实施例的流程图，其中第一磁盘表面上的伺服扇区被读取以生成物理位置测量值，其被转换为用于伺服控制磁头的虚拟位置测量值。
图2D示出根据一个实施例的伺服控制系统，其包括用于将物理位置测量值转换为虚拟位置测量值的转换操作。
图3A示出一个实施例，其中从每个磁盘表面的物理位置测量值的转换由相应的线性函数表示，该函数考虑了每个磁盘表面上的伺服磁道的实际径向密度与标称径向密度之间的差。
图3B示出一个实施例，其中伺服区边界被限定在目标虚拟位置处(跨越磁盘表面的共同径向位置)。
图4示出一个实施例，其中磁盘表面上的伺服磁道被分组以形成伺服区，其中伺服数据速率跨越伺服区变化。
具体实施方式
图2A和图2B示出根据一个实施例的磁盘驱动器形式的数据存储设备，其中磁盘驱动器包括第一磁盘表面161和在第一磁盘表面161上方被致动的第一磁头221，第一磁盘表面161包括由伺服扇区200-20N限定且以第一径向密度记录的伺服磁道18。磁盘驱动器还包括控制电路系统24，在一个实施例中，其被配置为执行图2C的流程图，其中第一磁盘表面上的伺服扇区被读取以生成第一物理位置测量值(块26)，第一物理位置测量值被转换为对应于不同于第一径向密度的伺服磁道的标称径向密度的第一虚拟位置测量值(块28)。基于第一虚拟位置测量值在第一磁盘表面上方伺服控制第一磁头(块30)。
图2D示出根据一个实施例的伺服控制系统，其中当读取伺服扇区时从第一磁头221发出的读信号32在块34处被解调为物理位置测量值36。物理位置测量值可以表示为磁道地址和/或由基于伺服扇区中的读取伺服脉冲产生的伺服磁道的一部分表示。物理位置测量值36在块38处被转换为虚拟位置测量值40，从目标位置42减去虚拟位置测量值40以生成位置误差信号(PES)44。伺服控制器46使用任何合适的伺服补偿器处理PES44，以生成应用到音圈电机(VCM)50的控制信号48。VCM50围绕枢轴旋转致动器臂52以便沿着减小PES的方向在磁盘表面161上方径向移动磁头221。
在一个实施例中，将通过读取伺服扇区产生的物理位置测量值转换为表示伺服磁道的标称径向密度的虚拟位置测量值降低伺服控制系统的复杂度，并且使磁盘表面能够被伺服写入，以实现伺服磁道的任何期望径向密度。例如，磁头的特定方面(例如，写元件和/或读元件的几何形状，和/或读元件的灵敏度)可以为具体磁头/磁盘表面组合指定最佳的伺服磁道径向密度。与设计伺服控制系统补偿跨越不同磁盘表面的伺服磁道的不同径向密度不同，在一个实施例中，伺服控制系统被设计为基于由标称径向密度表示的虚拟伺服磁道操作。
在一个实施例中，虚拟伺服磁道的标称径向密度可以被限定用于一组磁盘驱动器，使得伺服控制系统可以在该组磁盘驱动器上相同地操作。例如，在一个实施例中，每个磁盘驱动器可以包括单个磁盘表面，该单个磁盘表面具有由伺服扇区限定并以具体径向密度记录的伺服磁道。然而，每个磁盘驱动器的伺服控制系统可以在每个磁盘驱动器将物理位置测量值转换为虚拟位置测量值之后，跨越磁盘驱动器相同地操作(operatethesame)。在图2B示出的另一个实施例中，每个磁盘驱动器可以包括多个磁盘表面(例如，四个磁盘表面161-164)，其中磁头在每个磁盘表面上方被致动。可以以不同径向密度记录每个磁盘表面的伺服磁道，使得当磁头处于每个磁盘表面的共同具体径向位置时，由于伺服磁道的不同径向密度，最终的物理位置测量值跨越磁盘表面会不同。然而，在将每个磁盘表面的物理位置测量值转换为虚拟位置测量值之后，伺服控制系统可以跨磁盘表面相同地操作。
图3A示出根据一个实施例的通过读取每个磁盘表面的伺服扇区产生的物理位置测量值(垂直轴线)相对于转换后的对应虚拟位置测量值(水平轴线)之间的关系。在该实施例中，物理位置测量值与虚拟位置测量值之间的转换由下面的线性函数表示：
y＝m-1(x-b)+c
其中y表示虚拟位置测量值，x表示物理位置测量值，m表示线的斜率，以及b和c为任意偏移。在图3A的实例中，斜率m0表示伺服磁道的标称径向密度，斜率m1表示第一磁盘表面上的伺服磁道的径向密度，以及斜率m2表示第二磁盘表面上的伺服磁道的径向密度。在该示例性实施例中，第一磁盘表面上的伺服磁道的径向密度大于标称径向密度，而第二磁盘表面上的伺服磁道的径向密度小于标称径向密度。因此，当第一和第二磁头在相同的径向位置(由虚拟位置yi表示)中时，第一磁盘表面的物理位置测量值x1将大于对应的标称物理位置测量值x0，而第二磁盘表面的物理位置测量值x2将小于对应的标称物理位置测量值x0。然而，当(例如使用补偿不同径向密度的转换函数)转换物理位置测量值时，产生的第一和第二磁头两者的虚拟位置测量值将相同。
在图3A中示出的一个实施例中，当第一和第二磁头在偏移c表示的径向位置中时，每个磁盘表面的物理位置测量值将等于标称物理位置测量值(即，在斜率m0、m1和m2限定的线的交点处)。在一个实施例中，该径向位置可以识别边界伺服磁道，诸如，第一伺服磁道(伺服磁道0)。然而，在另一个实施例中，该径向位置可以表示任何虚拟位置测量值和任何对应的伺服磁道号。在一个实施例中，用于将物理位置测量值转换为虚拟位置测量值的至少一个参数可以存储在偏移c表示的径向位置处的至少一个磁盘表面上。以这种方式，伺服控制系统可以寻道该径向位置的磁头而不需要执行从物理到虚拟的转换，因为在该径向位置处物理位置测量值和虚拟位置测量值相等。换句话说，当磁盘驱动器被初始化时(例如，上电时)，伺服控制系统可以寻道由偏移c表示的径向位置的磁头，并且从至少一个磁盘表面读取转换参数，而不管每个磁盘表面上的伺服磁道的径向密度。一旦转换参数已经成功重新获得，伺服控制系统可以使用转换操作寻道任何磁盘表面的任何径向位置(由虚拟位置测量值表示的)。
在图3A的实施例中，从物理位置测量值到虚拟位置测量值的转换由线性函数表示。然而，在其他实施例中，转换可以以任何合适的方式(诸如非线性函数(例如，多项式函数)或分段线性函数)表示。例如，在一个实施例中，数据磁道的径向密度可以跨越每个磁盘表面变化(例如，在外径附近减小)，并且因此需要更复杂的函数表示物理位置测量值和对应的虚拟位置测量值之间的关系。在一个实施例中，从物理位置测量值到虚拟位置测量值的转换可以使用基于转换函数生成的合适查找表实施。在一个实施例中，查找表可以表示转换函数的离散数据点，其中内插和/或外推可以用于填充丢失数据点，这作为正常操作期间的转换过程的部分。
在一个实施例中，第一和第二磁盘表面的伺服磁道被分组以限定伺服区，并且每个伺服区的伺服数据速率跨越伺服区变化。图4示出该实施例的一个示例，其中磁盘表面16i的伺服磁道18被分组以限定三个伺服区(Z1到Z3)，其中伺服扇区的伺服数据速率在伺服区内保持基本恒定，但跨越伺服区时变化(例如，朝向外径区增加以实现更恒定的线性比特密度)。图3B示出一个实施例，其中伺服区的边界可以跨越磁盘表面(例如，跨越第一和第二磁盘表面)径向对齐，使得当执行磁头切换时，伺服区过渡发生在已知径向位置处(虚拟位置测量值)。在一个实施例中，图3B中的偏移c可以表示伺服区Z1(例如，伺服磁道0)的边界，而在其他实施例中，伺服区Z1的边界可以以不同径向位置和对应的虚拟位置测量值限定。
在一个实施例中，可以在将伺服扇区记录在每个磁盘表面上之前确定限定图3B中的伺服区(例如，SEAM1和SEAM2)的边界的径向位置，并且在一个实施例中，跨越一组磁盘驱动器的径向位置可以是相同位置。相应地，在一个实施例中，表示为虚拟位置测量值的伺服区的边界可以被转换为每个磁盘表面的对应的物理位置测量值，使得当伺服写入每个磁盘表面时，可以基于对应于伺服区边界的物理位置测量值调节伺服扇区的伺服数据速率。伺服扇区可以以任何合适的方式被伺服写到每个磁盘表面上，该合适的方式包括在将每个磁盘插入产品磁盘驱动器之前使用外部介质写入器。在另一个实施例中，每个产品磁盘驱动器内部的控制电路系统24可以自伺服写伺服扇区，包括当到达伺服区的边界时调节伺服数据速率。
任何合适的控制电路系统(诸如，任何合适的集成电路(一个或更多个))可以用于实施上述实施例中的流程图。例如，可以在读通道集成电路中或与读通道分离的部件(诸如，磁盘控制器)中实施控制电路系统，或上述某些操作可以由读通道执行，而其他操作由磁盘控制器执行。在一个实施例中，读通道和磁盘控制器被实施为单独的集成电路，而在一个替代实施例中，它们可以被制造成单个集成电路或片上系统(SOC)。此外，控制电路系统可以包括实施为单独的集成电路、集成到读通道或磁盘控制器电路或集成到SOC中的合适前置放大器电路。
在一个实施例中，控制电路系统包括执行指令的微处理器，指令可操作以使微处理器执行本文描述的流程图。指令可以存储在任何计算机可读介质中。在一个实施例中，它们可以存储在微处理器外部的非易失性半导体存储器或与SOC中的微处理器集成的非易失性半导体存储器中。在另一个实施例中，指令存储在磁盘上，并且当磁盘驱动器被上电时，指令被读入易失性半导体存储器中。在另一个实施例中，控制电路系统包括合适的逻辑电路系统，诸如状态机电路系统。
虽然上述实例针对磁盘驱动器，但是各种实施例不限于磁盘驱动器并且能够应用到其他数据存储设备和系统，诸如磁带驱动器、固态驱动器、混合驱动器等。此外，一些实施例可以包括电子设备(诸如计算设备、数据服务器设备、介质内容存储设备等)，所述电子设备包括存储介质和/或如上所述的控制电路系统。
上述各种特征和过程可以彼此独立使用，或可以以各种方式结合。所有可能的组合和子组合旨在落入本公开的范围内。此外，在一些实施方式中可以省略某些方法、事件或过程块。本文描述的方法和过程也不限于任何特定顺序，并且与其相关的块或状态能够以合适的其他顺序执行。例如，公开的任务或事件可以以不同于具体公开的顺序的顺序执行，或多个任务或事件可以在单个块或状态中组合。示例任务或事件可以串行、并行或以某种其他方式执行。任务或事件可以被添加到所公开的示例实施例中或从所公开的示例实施例中移除。本文描述的示例系统和部件可以不同于所描述的那些而被配置。例如，元件可以被添加到所公开的示例实施例、从所公开的示例实施例中移除或与所公开的示例实施例相比被重新布置。
虽然已经描述某些示例实施例，但是这些实施例仅以示例的方式被呈现，并且不旨在限制本文公开的发明的范围。因此，上述描述并不旨在暗示任何具体特征、特性、步骤、模块或块是必要的或不可缺少的。实际上，本文描述的新颖方法和系统可以以各种其他形式体现；此外，在不脱离本文公开的实施例的精神的情况下，可以对本文描述的方法和系统的形成进行替换和改变。
Claims (26)
1.一种数据存储设备，包括：
第一磁盘表面，其包括由伺服扇区限定且以第一径向密度记录的伺服磁道；
第一磁头，其在所述第一磁盘表面上方被致动；和
控制电路系统，其被配置为：
读取所述第一磁盘表面上的伺服扇区以生成第一物理位置测量值；
将所述第一物理位置测量值第一转换为第一虚拟位置测量值，所述第一虚拟位置测量值对应于不同于所述第一径向密度的伺服磁道的标称径向密度；以及
基于所述第一虚拟位置测量值在所述第一磁盘表面上方伺服控制所述第一磁头。
2.根据权利要求1所述的数据存储设备，进一步包括：
第二磁盘表面，其包括由伺服扇区限定且以不同于所述第一径向密度的第二径向密度记录的伺服磁道；和
第二磁头，其在所述第二磁盘表面上方被致动；
其中所述控制电路系统进一步被配置为：
读取所述第二磁盘表面上的伺服扇区以生成第二物理位置测量值；
将所述第二物理位置测量值第二转换为第二虚拟位置测量值，所述第二虚拟位置测量值对应于所述标称径向密度，其中所述第二径向密度不同于所述标称径向密度；以及
基于所述第二虚拟位置测量值在所述第二磁盘表面上方伺服控制所述第二磁头。
3.根据权利要求1所述的数据存储设备，其中所述控制电路系统进一步被配置为基于第一转换函数将所述第一物理位置测量值第一转换为所述第一虚拟位置测量值。
4.根据权利要求2所述的数据存储设备，其中所述控制电路系统进一步被配置为基于第二转换函数将所述第二物理位置测量值第二转换为所述第二虚拟位置测量值。
5.根据权利要求2所述的数据存储设备，其中当所述第一磁头和所述第二磁头两者都定位在第一径向位置时：
所述第一物理位置测量值基本等于所述第二物理位置测量值；并且
所述第一虚拟位置测量值基本等于所述第二虚拟位置测量值。
6.根据权利要求5所述的数据存储设备，其中在所述第一径向位置处，所述第一虚拟位置测量值和所述第二虚拟位置测量值识别边界伺服磁道。
7.根据权利要求5所述的数据存储设备，其中所述控制电路系统进一步可操作以在所述第一径向位置处从所述第一磁盘表面和所述第二磁盘表面中的至少一个读取所述第一转换和所述第二转换的至少一个参数。
8.根据权利要求5所述的数据存储设备，其中当所述第一磁头和所述第二磁头两者都定位在第二径向位置时：
所述第一物理位置测量值不等于所述第二物理位置测量值；并且
所述第一虚拟位置测量值基本等于所述第二虚拟位置测量值。
9.根据权利要求8所述的数据存储设备，其中：
所述第一磁盘表面和第二磁盘表面的所述伺服磁道被分组以限定伺服区；
每个伺服区的伺服数据速率跨越所述伺服区变化；并且
所述第二径向位置限定所述第一磁盘表面和第二磁盘表面两者上的伺服区之间的伺服区边界。
10.根据权利要求9所述的数据存储设备，其中所述控制电路系统进一步被配置为伺服写所述第一磁盘表面和所述第二磁盘表面上的所述伺服扇区，使得所述第二径向位置限定所述伺服区边界。
11.根据权利要求1所述的数据存储设备，其中：
当所述第一磁头定位在第一径向位置时，所述第一物理位置测量值基本等于所述第一虚拟位置测量值；并且
当所述第一磁头定位在第二径向位置时，所述第一物理测量值不等于所述第一虚拟位置测量值。
12.根据权利要求11所述的数据存储设备，其中在所述第一径向位置处，所述第一虚拟位置测量值识别边界伺服磁道。
13.根据权利要求11所述的数据存储设备，其中所述控制电路系统进一步可操作以在所述第一径向位置处从所述第一磁盘表面读取所述第一转换的至少一个参数。
14.一种操作数据存储设备的方法，所述方法包括：
读取第一磁盘表面上的伺服扇区以生成第一物理位置测量值；
将所述第一物理位置测量值第一转换为第一虚拟位置测量值，所述第一虚拟位置测量值对应于伺服磁道的标称径向密度，所述标称径向密度不同于所述第一磁盘表面上的伺服磁道的第一径向密度；以及
基于所述第一虚拟位置测量值在第一磁盘表面上方伺服控制第一磁头。
15.根据权利要求14所述的方法，进一步包括：
读取第二磁盘表面上的伺服扇区以生成第二物理位置测量值；
将所述第二物理位置测量值第二转换为第二虚拟位置测量值，所述第二虚拟位置测量值对应于伺服磁道的所述标称径向密度，其中所述第二磁盘表面上记录的伺服磁道的第二径向密度不同于所述第一径向密度；以及
基于所述第二虚拟位置测量值在第二磁盘表面上方伺服控制第二磁头。
16.根据权利要求14所述的方法，进一步包括基于第一转换函数将所述第一物理位置测量值第一转换为所述第一虚拟位置测量值。
17.根据权利要求15所述的方法，进一步包括基于第二转换函数将所述第二物理位置测量值第二转换为所述第二虚拟位置测量值。
18.根据权利要求15所述的方法，其中当所述第一磁头和所述第二磁头两者都定位在第一径向位置时：
所述第一物理位置测量值基本等于所述第二物理位置测量值；并且
所述第一虚拟位置测量值基本等于所述第二虚拟位置测量值。
19.根据权利要求18所述的方法，其中在所述第一径向位置处，所述第一虚拟位置测量值和所述第二虚拟位置测量值识别边界伺服磁道。
20.根据权利要求18所述的方法，进一步包括在所述第一径向位置处从所述第一磁盘表面和所述第二磁盘表面的至少一个读取所述第一转换和所述第二转换的至少一个参数。
21.根据权利要求18所述的方法，其中当所述第一磁头和所述第二磁头两者都定位在第二径向位置时：
所述第一物理位置测量值不等于所述第二物理位置测量值；并且
所述第一虚拟位置测量值基本等于所述第二虚拟位置测量值。
22.根据权利要求18所述的方法，其中：
所述第一磁盘表面和第二磁盘表面的所述伺服磁道被分组以限定伺服区；
每个伺服区的伺服数据速率跨越所述伺服区变化；并且
所述第二径向位置限定所述第一磁盘表面和第二磁盘表面两者上的伺服区之间的伺服区边界。
23.根据权利要求22所述的方法，进一步包括伺服写所述第一磁盘表面和所述第二磁盘表面上的所述伺服磁道，使得所述第二径向位置限定所述伺服区边界。
24.根据权利要求14所述的方法，其中：
当所述第一磁头定位在第一径向位置时，所述第一物理位置测量值基于等于所述第一虚拟位置测量值；并且
当所述第一磁头定位在第二径向位置时，所述第一物理位置测量值不等于所述第一虚拟位置测量值。
25.根据权利要求24所述的方法，其中在所述第一径向位置处，所述第一虚拟位置测量值识别边界伺服磁道。
26.根据权利要求24所述的方法，进一步包括在所述第一径向位置处，从所述第一磁盘表面读取所述第一转换的至少一个参数。
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US14/298,734 US8941945B1 (en) | 2014-06-06 | 2014-06-06 | Data storage device servoing heads based on virtual servo tracks |
| US14/298,734 | 2014-06-06 |
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| CN105304098A true CN105304098A (zh) | 2016-02-03 |
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| US (1) | US8941945B1 (zh) |
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| CN108630233A (zh) * | 2017-03-16 | 2018-10-09 | 株式会社东芝 | 磁盘装置 |
| CN111462779A (zh) * | 2019-01-19 | 2020-07-28 | 西部数据技术公司 | 采用标称解耦器和自适应多致动器解耦器的数据存储设备 |
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-
2014
- 2014-06-06 US US14/298,734 patent/US8941945B1/en active Active
-
2015
- 2015-06-05 CN CN201510304931.5A patent/CN105304098A/zh active Pending
-
2016
- 2016-06-23 HK HK16107326.2A patent/HK1219345A1/zh unknown
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108630233A (zh) * | 2017-03-16 | 2018-10-09 | 株式会社东芝 | 磁盘装置 |
| CN108630233B (zh) * | 2017-03-16 | 2019-12-31 | 株式会社东芝 | 磁盘装置 |
| CN111462779A (zh) * | 2019-01-19 | 2020-07-28 | 西部数据技术公司 | 采用标称解耦器和自适应多致动器解耦器的数据存储设备 |
| CN111462779B (zh) * | 2019-01-19 | 2021-09-07 | 西部数据技术公司 | 采用标称解耦器和自适应多致动器解耦器的数据存储设备 |
| CN113539302A (zh) * | 2020-04-17 | 2021-10-22 | 西部数据技术公司 | 交错存取操作以促进两个磁盘表面的同时存取的数据存储装置 |
Also Published As
| Publication number | Publication date |
|---|---|
| HK1219345A1 (zh) | 2017-03-31 |
| US8941945B1 (en) | 2015-01-27 |
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