aps hard drive protection technology"
The composition of APS technology
ASP hard drive protection technology is composed of an acceleration sensing chip embedded on the motherboard and a pre-installed The system consists of vibration prediction management software. By monitoring the angle, vibration, and impact of the ThinkPad notebook (that is, monitoring the changes in horizontal and vertical acceleration), it is decided whether to retract the hard disk head from the working state to the head stop area, thereby reducing Impact damage to the hard disk protects the hard disk and the data in the hard disk. The vibration prediction management software receives the corresponding signals from the acceleration sensor chip and determines which ones are harmful to the hard disk and which ones are regular movements. The software will ignore regular movements that cannot cause damage to the hard disk, and for movements that may cause damage to the hard disk, the vibration prediction management software will immediately transfer the information to the hard disk to quickly retract the magnetic head to the stop area when the notebook is turned off or when the computer is turned off. When the system is in startup state, the APS function will not be activated.
How APS technology works
When the laptop hard disk is working, the hard disk head moves above the disk to read data. It is assumed that when the impact force is less than 200G within 2 milliseconds, the ThinkPad notebook's shell and shock-proof design can generally be used to absorb the shock to avoid damage to the hard drive. When the impact force exceeds 200G within 2 milliseconds, the damage will occur. It will increase with the increase of impact energy.
When the hard disk is in non-working state, the magnetic head is in the stop zone, and the hard disk can withstand a maximum impact of 800G in 1 millisecond. When the impact exceeds 800G/1 millisecond. Afterwards, the damage will increase as the impact energy increases (see the function diagram on the right side of the figure). That is to say, if the hard disk head can be returned to the stop area in time, the hard disk can endure greater damage than in working conditions. The impact will not be damaged. IBM APS technology is based on the above principle. After predicting the possibility of impact, it will promptly move the magnetic head to the stop area to protect the hard disk.
According to a large number of actual surveys, notebooks Most of the cases when computers are dropped while working are from the desktop or the knee, that is, from a height of less than 120cm (usually a person’s knee height is 50cm and the desktop height is 80cm). How can the ThinkPad be removed before it hits the computer? The key to the problem is the return of the magnetic head.
1. The time of return of the magnetic head. After testing, the return time of the magnetic head is from receiving the control signal to completing the operation. Depending on the track position of the magnetic head, it is about 100 milliseconds to 500 milliseconds. For free falls within a height of 20cm, the laptop's shell and shock-proof design can generally resist the impact, so we only need to pay attention to drops above 20cm. . And the time for a laptop to fall from a height of 20cm to 120cm is 202 milliseconds to 495 milliseconds. Combined with the short delay before the laptop is dropped, the test shows that more time is usually expected to occur than the fall. This ensures that the magnetic head can return to its position in time before the laptop is hit, effectively protecting the disk.
2. Impact force problem
What kind of impact does a laptop have to withstand before the hard drive will receive an impact of more than 800G? We know that the impact force on the hard drive is caused by a number of factors. determined by factors. The first is the relative height and initial speed of the laptop falling. Generally speaking, most laptops fall from their knees or desktop to the floor when they are in working condition. The relative height does not exceed 120cm. The initial speed in the vertical direction is basically OK. Ignore; the second is the surface the laptop hits. Hard, inelastic surfaces (such as cement floors) can cause greater impact, and soft and elastic surfaces (such as wooden floors or carpeted floors) can slightly cushion the impact. Collision, thus causing smaller impact; again, it is the shell design and shock-proof design of the laptop itself.
In order to quantify the impact force on the hard drive under various circumstances, IBM laboratories conducted a large number of actual tests specifically for two scenarios: falling from the knee and falling from the desktop.
Relevant experimental data shows that if it falls from knee height (50cm) or desktop height (80cm) to a hard and inelastic cement floor, the probability of the hard drive receiving an impact force exceeding 200G due to the protection of the casing and impact-absorbing pad is approximately 50%, and the probability of exceeding 800G is no more than 2%.
3. Regular bumping problem
Once the APS function is turned on, it will always monitor the movement of the ThinkPad notebook. However, users often need to work on the move, such as using laptops in cars, trains, airplanes, etc., so bumps are inevitable. If these vibrations often trigger the APS to return the magnetic head to its original position, ThinkPad users will experience problems when using their laptops. I feel that the notebook runs intermittently, which affects work efficiency. However, APS technology has already taken this problem into consideration. It has the function of ignoring repeated vibrations, which can eliminate the concerns of mobile users. The impact caused by vehicle bumps is generally not enough to damage the hard drive, so most bumps will not trigger the APS function to return the magnetic head to its original position, thus effectively ensuring the smoothness of ThinkPad users using their laptops.
Intelligent vibration prediction and advanced head return operation, these important features of APS ensure that the hard drive and data on the ThinkPad notebook will not be easily affected by various impacts.