Write Assist Element Protrusion Slope Abnormality Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The write assist elements in data storage devices, such as HAMR and MAMR, are prone to thermal degradation and varying lifetimes, leading to unpredictable failures that can impact data quality and storage capacity, necessitating a method to detect abnormalities and prevent premature failure.
Innovation Solution
Periodic measurement of the protrusion of the write assist element to detect abnormalities by analyzing the slope of protrusion measurements, allowing for early detection of potential failures and remedial actions like redirecting data operations or designating a disk surface for cold storage, and recalibrating the write current to maintain data quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If write assist element (HAMR/MAMR) is used to improve data quality, then data quality is improved, but element lifetime becomes unpredictable and shorter
Solution Approach 1:
The system performs preliminary detection of protrusion changes before actual failure occurs. By monitoring the write assist element's protrusion over time and detecting abnormal slopes, the system can identify degradation trends early and take preventive actions such as redirecting data operations or designating cold storage surfaces, thereby preventing premature failure and maintaining reliability
Solution Approach 2:
The system implements continuous feedback monitoring by periodically measuring the protrusion of the write assist element during operation. The control circuitry analyzes the slope of protrusion measurements over time and provides feedback about the element's health status, enabling dynamic adjustment of operations to maintain both data quality and element reliability throughout its operational life
2Productivity
If write assist element operates continuously, then productivity is improved, but thermal degradation accelerates
Solution Approach 1:
The system replaces direct thermal monitoring with a mechanical/protrusion-based monitoring approach. Instead of measuring temperature directly or monitoring thermal effects, the system measures the physical protrusion of the write assist element, which changes predictably with thermal degradation. This substitution enables continuous operation monitoring while indirectly tracking thermal damage accumulation
Solution Approach 2:
The system monitors changes in the protrusion parameter of the write assist element over time. By tracking the slope of protrusion measurements, the system can detect thermal degradation effects without interrupting continuous operation. The parameter change in protrusion serves as an indicator of cumulative thermal stress, allowing productivity maintenance while managing thermal degradation risks
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables early detection of write assist element failures, allowing for proactive measures to maintain data integrity and storage capacity by identifying abnormal protrusion slopes indicative of impending failure, thereby extending the device's operational life and preventing data loss.
Implementation Method 1
Heat assisted magnetic recording (HAMR) is a recent development that improves the quality of written data by heating the disk surface during write operations in order to decrease the coercivity of the magnetic medium
Implementation Method 2
Microwave assisted magnetic recording (MAMR) is also a recent development that improves the quality of written data by using a spin torque oscillator (STO) to apply a high frequency auxiliary magnetic field to the media close to the resonant frequency of the magnetic grains
Implementation Method 3
a protrusion of the head toward the disk is periodically measured... An abnormality with the write assist element is detected when a slope of the protrusion measurements indicates the protrusion is increasing
Data Source
AI summary
A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a write assist element. Data is written to the disk using the write assist element. A protrusion of the head toward the disk is measured periodically, and an abnormality with the write assist element is detected when a slope of the protrusion measurements indicates the protrusion is increasing.