Head positioning control systems are required to improve the positioning accuracy and thus increase the recording capacity of hard disk drives (HDDs). Existing head positioning control systems employ a dual-stage actuator system comprising a voice coil motor (VCM) and a piezoactuator. The control system is a multi-input single-output system, and positioning controllers must be designed for both actuators. In this article, we propose a coupling controller design method for head positioning control systems of HDDs. The proposed method designs the controllers by considering the interaction between the VCM and the piezoactuator. It is more complex than the decoupling controller design method, which is widely used to design the controllers for the dual-stage actuator system. Nevertheless, it provides greater freedom in the controller design. The main advantage is, when the entire feedback loop is stabilized, the feedback loop for each actuator does not need to be stabilized. The design results show that the proposed design method can improve the positioning accuracy with comparison to the decoupling controller design. Moreover, the amount of the required stroke of the piezoactuator is decreased by using the coupling controller design.

中文翻译：

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HDD磁头定位控制系统MISO系统耦合控制器设计

需要磁头定位控制系统来提高定位精度，从而增加硬盘驱动器（HDD）的记录容量。现有的磁头定位控制系统采用双级致动器系统，包括音圈电机 (VCM) 和压电致动器。控制系统为多输入单输出系统，必须为两个执行器设计定位控制器。在本文中，我们提出了一种用于 HDD 磁头定位控制系统的耦合控制器设计方法。所提出的方法通过考虑 VCM 和压电执行器之间的相互作用来设计控制器。它比解耦控制器设计方法更复杂，它被广泛用于设计双级执行器系统的控制器。尽管如此，它在控制器设计中提供了更大的自由度。主要优点是，当整个反馈回路稳定时，每个执行器的反馈回路不需要稳定。设计结果表明，与解耦控制器设计相比，所提出的设计方法可以提高定位精度。此外，通过使用耦合控制器设计减少了压电执行器所需的行程量。