TECHNICAL SUPPORT
Published 2026-03-23
Have you ever encountered this situation - theservoyou bought either has no power to turn, or the movement is not smooth enough, or it gets hot and stops after a short time? The problem probably lies in the "heart" in its belly. What kind of motor is used for the steering gear directly determines its strength, accuracy, noise and lifespan. Today we are going to discuss more about the types of motors used inservos and what scenarios they are suitable for, so that you can have a clear idea when choosing a model next time.
The standardservothat we see most often is actually equipped with a DC brush motor. This kind of motor has a simple structure, is affordable and easy to control. You power it on and it turns, and it reverses when you change the direction. It's especially suitable for cost-sensitive projects. For example, in scenes such as toy robots, simple robot arm joints, and car model steering, brushed motors are enough.
However, brushed motors have a natural shortcoming-the carbon brushes inside will wear out. After you use it for a period of time, you may find that the servo moves slowly, vibrates, or simply becomes unresponsive. This is caused by the carbon brushes being worn out or too much carbon deposits. So if the product you are making requires continuous operation for a long time, such as industrial equipment that works for more than eight hours a day, then brushed motors are not suitable.
If you need a servo to run fast, be powerful, and be durable, then you should look at brushless motor servos. Brushless motors have no carbon brushes and rely on electronic control to reverse direction, so there is almost no wear and tear, and their lifespan can easily reach tens of thousands of hours. Moreover, it is highly efficient, generates little heat, and can rotate at higher speeds. It is particularly suitable for use in racing drones, industrial robots, and high-end gimbals.
Of course, brushless motor servos also have a "threshold" - the price is much higher than brushed ones, and the drive circuit is more complex. Some cheap brushless servos are actually "pseudo-brushless", with a brushed motor inside and a "brushless" casing. You have to be careful when purchasing. For a truly good brushless servo, the manufacturer will clearly mark the "brushless motor" and the corresponding driver solution.
There is also a motor called a coreless motor, which is an upgraded version of the DC brush motor. The biggest feature is that the rotor has no iron core and is like a cup-shaped air-core coil, so the inertia is very small when it rotates. This means that the response speed of the coreless servo is very fast, there is almost no delay in starting and stopping, and the control precision is high, and the movements are particularly delicate.
Where is this kind of motor used? For example, bionic robots, dexterous hands, and precision medical equipment are scenarios that require high movement smoothness and response speed. Its shortcomings are also obvious - the price is more expensive than ordinary brushed motors, and because of its fine structure, its impact resistance is slightly worse. If your product is often bumped or beaten, you should be careful when choosing a coreless servo.
When you get a servo, you can't take it apart to see the motor inside, but there are several methods that can help you make a quick judgment. The first is to listen to the sound. When a good motor is running, the sound is even and low. If there is a sharp whistling sound or obvious stuck feeling, there may be something wrong with the motor. The second is to touch the temperature. After running for a few minutes without load, it is normal for the shell to be warm but not hot. If it is particularly hot, be careful.
In addition, looking at the parameter table is also key. Reliable manufacturers will clearly indicate the motor type, rated voltage, no-load current, and locked-rotor torque. If the parameter list only says "high performance motor" or does not write the motor type at all, then it is most likely that you are using a cheap product. You can ask customer service directly or check the official website to see if they have detailed technical instructions.
Many people easily fall into a trap when choosing a servo - they only look at the torque, not the motor type. For example, someone buys a high-torque servo that costs tens of yuan, but after installing it, they find that the response is as slow as a snail. That is because it uses an ordinary brushed motor and the response speed cannot keep up. Some people bought a brushless servo, but the power supply was too small, causing the motor to fail to perform at all and spending more money in vain.
Another pitfall is the superstitious belief that "all metal gears" are good. Gears and motors are matched. The motor has a large torque, so of course the gears must be made of metal; but if the motor itself is weak, using metal gears will increase the load and slow down the movement. The correct idea is to first determine the torque and speed you need, then look at which motor can match it, and finally choose the gear material.
If your project is a consumer-grade product, such as educational robots, smart toys, and model cars, then ordinary brushed motor servos are completely sufficient and have the highest cost performance. If it is a commercial or industrial-grade product, such as an automatic camera gimbal, logistics robot, or automation equipment, it is recommended to buy a brushless motor servo. Although the initial investment is higher, it can avoid the trouble of frequent maintenance and replacement in the later period.
Another situation is creative products, such as bionic palms, omnidirectional mobile platforms, and high-precision 3D printing heads. For those that require high precision in movements, you can consider coreless servos or brushless servos with encoders. When selecting a model, don’t just look at one parameter. You must weigh torque, speed, accuracy, life and cost together to find the balance point that best suits your project.
After reading the differences between these types of steering gear motors, which motor do you think is more suitable for the product you are making? Welcome to chat about your application scenarios in the comment area, or share the steering gear pitfalls you have experienced, so that more friends can avoid detours.
Update Time：2026-03-23
Contact Kpower's product specialist to recommend suitable motor or gearbox for your product.
