Multi-Head Disk Drive Eliminating Mechanical Actuator Latency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional hard disk drives face high access latency and data transmission rate limitations due to their mechanical nature, with moving read-write heads requiring time to seek and align with data tracks, while solid state drives are faster but more expensive and less capacity-efficient.
Innovation Solution
Implementing multiple read-write heads mounted over rotating platters, eliminating the need for a mechanical actuator assembly, allowing simultaneous read and write operations across all tracks without movement, thereby reducing latency and increasing throughput.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If traditional mechanical actuator assembly is used to move read-write head to desired track, then the disk drive can access data on any track, but access latency is high (4-15 ms seek time plus rotational latency)
Solution Approach 1:
The patent divides the single read-write head into multiple read-write heads (at least two), with each head assigned to serve specific tracks. This segmentation eliminates the need for mechanical movement between tracks, as each head remains stationary over its assigned tracks, reducing access latency from 4-15 ms to significantly lower values while eliminating complex actuator mechanisms.
Solution Approach 2:
The patent replaces the mechanical actuator assembly with a static multi-head configuration. Instead of using mechanical components (voice coil, actuator arm, motor) to move the read-write head between tracks, the system uses multiple fixed heads positioned over different tracks, substituting mechanical motion with a stationary parallel architecture.
2Speed
If solid state drives are used instead of hard drives, then access speed is faster, but cost is significantly higher and capacity ratio is reduced
Solution Approach 1:
The patent creates a hybrid storage system that combines the advantages of both HDD and SSD. The multiple read-write heads can simultaneously service multiple tracks on magnetic platters, providing fast access speeds similar to SSD while maintaining the high storage capacity and lower cost characteristics of magnetic storage, thus achieving multi-functionality in terms of performance and capacity.
3Productivity
If single read-write head is used on rotating platter, then device structure is simple, but data transmission rate is limited by sequential access requirement
Solution Approach 1:
The patent enables continuous data transmission by having multiple read-write heads simultaneously reading from or writing to different tracks. This parallel operation eliminates the idle time that occurs with single-head sequential access, as the system can continuously service multiple tracks without waiting for rotational alignment, thereby increasing data transmission rate while maintaining manageable device complexity.
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
Significantly reduces access time and increases data throughput by eliminating the need for mechanical head movement, with average latency reduced from 4.2 ms to 0.084 ms with sufficient read-write heads, and enabling multiple simultaneous operations.
Implementation Method 1
The read-write heads can read data stored on the rotatable platters and can write data to the rotatable platters
Data Source
AI summary
The embodiments of the invention improve the traditional disk drives by eliminating the mechanical actuator assembly that moves the read-write head attached to the actuator assembly, and replacing it with multiple read-write heads mounted over one or more rotating platters. The number of the read-write heads is preferably sufficiently large so that the read-write heads cover all tracks on the one or more rotating platters. In one embodiment, a disk includes a rotatable platter, a central spindle to rotate the rotatable platter arounds an axis, an electric motor to drive the central spindle, and multiple read-write heads mounted over the rotatable platter. In one embodiment, the platter includes multiple tracks arranged in form of concentric circles, where each of the read-write heads performs read-write operations on one of the tracks, and each track is assigned at least one of the multiple read-write heads.