Nowadays, the importance of the vibration unit in smartphones has been much greater than in the past. A few years ago, mobile phone motors were more used for call vibration and a small amount of interface feedback. Now that full screens have become popular, the Home button and the return button have become virtual. The keys have even been replaced by full-screen gestures, so that more and more vibration scenes are required.
Rotor motor
The rotor motor is similar to the motor used in the four-wheel drive we used as a child. The principle is that a small motor drives the eccentric rotor to rotate, which generates vibration. There are two types of micro motor rotor motors and flat rotor motors. Due to the simple structure and mature technology, the cost of such motors is very low. For example, the flat type is less than 1 yuan, and the micro motor type is 2 yuan.
In terms of experience, the rotor motor can only provide a sense of vibration. The biggest disadvantage is that the response speed is slow, and it cannot achieve emergency start and emergency stop. There are not so many fancy. The flat rotor motor, because the eccentric wheel itself is the rotor, has a clear sense of starting acceleration, and it feels very fleshy and has a sense of procrastination. To put it simply, it means that the power is turned to the power off, at most, it can provide a stronger sense of shock by increasing the current. So the rotor motor basically has nothing to do with the experience.
Linear motor
Similar to a pile driver, it consists of a stator and a mover. The principle is to use multiple sets of electromagnetic coils to repel the mass bearing the permanent magnets, and reciprocate laterally in the cavity. The frequency of the motion depends on the frequency of the drive signal. Because there are multiple sets of electromagnetic coils inside the linear motor and need to be driven by the driving IC, its vibration sense is adjustable and has directionality.
The linear motor has a fast response speed, strong vibration sensation, vibration direction, adjustable vibration frequency and waveform, which can achieve more complex and customized vibration effects.
In addition, there is a Z-axis linear motor, which has a thicker appearance than a flat rotor. The working principle is like tapping the table with your fingers. It is one-way and unidirectional, plus inconsistent start and stop, there will be a buzzing feeling. However, the buzz of the Z axis is powerful at shortcomings. The reason why it is not as good as the X axis linear motor is that the stroke is short and the response speed is slow.
The linear motor and the rotor motor are not only different in structure, but the driving schemes of the two are also very different. The linear drive chip can output a peak voltage of up to 10V. Under high-voltage drive, it can further shorten the start-stop time and increase the vibration intensity. The dozens of vibration waveforms built into the driver chip can also be matched with audio decoders to achieve audio vibration. Through later experience optimization, accurate and targeted vibration feedback can be achieved in a variety of scenarios. The rotor motor neither supports high-voltage drive output nor built-in drive waveforms.
How to measure the quality of a motor
Start and stop time and vibration intensity
Start and stop time and vibration amount (representing vibration intensity) are two key indicators to measure the quality of a motor. This is also whether it can achieve a mechanical keyboard-style feedback and "short and powerful" The essential.
Everything about the vibration motor: https://www.bilibili.com/video/av90483462
