Control of a Micro-Actuator for the Hard Disk Drive using Self-Sensing Actuation

微驱动器将是实现硬盘驱动器高速、高精度磁头定位控制的重要技术。在传统的硬盘驱动器中，音圈电机(VCM)驱动悬架，将滑块定位在所需的数据磁道上。磁头堆叠和悬挂组件的结构共振模式是硬盘驱动器中实现更高磁头定位伺服性能的主要限制因素之一。硬盘驱动器(HDD)中的悬挂组件可以由高速旋转磁盘产生的气流、由部件的共振振动模式引起的磁头/滑块的非圆形轨道运动以及其他外部干扰来激励。能够处理这些问题的伺服系统需要非常高的伺服带宽和位置误差信号采样频率。位置误差信号的采样频率受到传统伺服系统数据存储效率的限制。Active C…要更好地控制这些问题和部件的振动，需要额外的振动传感器和执行器。许多研究人员建议增加额外的振动传感器和执行器。例如，已经提出了使用压电致动器来驱动两级伺服系统的悬架，其中两个压电片中的一个用作振动传感器，另一个用作致动器。针对传统微致动器只有一半作为传感器的缺点，提出了一种硬盘驱动器微致动器的自感知控制方案。该微执行器为悬架驱动型。微致动器采用安装在悬架组件上的PZT致动器对。该自感知微执行器可用于形成组合的驱动和传感机构。给出并比较了直接速度反馈(DVR)、直接位置反馈(DPF)和位置正反馈(PPF)的反馈控制效果。实验的目的是验证这些自感知方法作为微执行器振动抑制控制的可行性。人工神经网络可以有效地用于非线性动态系统的辨识和控制，如带有悬架组件的柔性微执行器和自感知系统。为了解决这些问题，提高硬盘驱动器两级伺服系统的性能，提出了一种利用自感知传感器抑制悬架系统振动的自增益校正神经网络控制方法。较少

A micro-actuator will be important technology to achieve high-speed and highly precise head positioning control for hard disk drives. In conventional hard disk drives, a voice-coil motor (VCM) actuates the suspension, positioning the slider over the desired data track. Structural resonance modes of the head stack and suspension assembly are one of the major limiting factors for achieving higher head-positioning servo performance in hard disk drives. A suspension assembly in the hard disk drive (HDD) can be excited by the airflow generated from a high-speed rotating magnetic disk, a non-circular track motion of the head/slider, which is caused by the resonance vibration modes of components, and other external disturbances. A servo system that can cope with these problems requires a very high servo bandwidth and position error signal sampling frequency. The sampling frequency of the position error signal is limited by the data storage efficiency of the conventional servo system. Active c … More ontrol of these problems and the vibration of components require additional vibration sensors and actuators. Many researchers have proposed the addition of extra vibration sensors and actuators. For example, the use of a piezoelectric actuator to actuate the suspension for the dual-stage servo system has been proposed, whereby one of the two piezoelectric strips is used as a vibration sensor and the other is used as the actuator. However, using only half of the conventional micro-actuator pair as the sensor decreases the usual effect of the actuator by half and is not efficient.In this project, self-sensing control of a micro-actuator for the hard disk drive is presented. The micro-actuator is a suspension driving type. The micro-actuator uses a PZT actuator pair, installed on the assembly of the suspension. The self-sensing micro actuator can be used to form a combined actuation and sensing mechanism. Feedback control results of direct velocity feedback (DVR) and direct position feedback (DPF) and positive position feedback (PPF) are presented and compared. The objective of the experiments are to verify the feasibility of these self-sensing approaches as a vibration suppression control of the micro-actuator. Artificial neural networks can be used effectively for the identification and control of nonlinear dynamical systems, such as a flexible micro-actuator with a suspension assembly and a self-sensing system. In the present project, in order to solve these problems and improve the performance of the dual-stage servo system for the HDD, a self gain tuning neural-network control has been proposed by utilizing the self-sensing sensors to damp the suspension assembly vibrations. Less