TECHNICAL SUPPORT
Published 2026-03-26
Are you working on a creative project, only to find that ordinaryservos can only turn one angle, and are completely unable to achieve the effect of a wheel turning all the time or a conveyor belt running non-stop? Don't worry, the 9g continuous rotating microservois tailor-made for this scenario. It is small in size and easy to control, and is especially suitable for products that require continuous movement such as robots, cars, and robotic arms. Today we will talk about how to choose and use this small steering gear so that your innovative projects can be implemented more smoothly.
You may be wondering what exactly such a small servo can do. In fact, it is particularly popular in the maker circle. It is most commonly used in micro-robots, such as the driving wheels of cars or the joints of robotic arms. Because it can rotate 360 degrees without any angle restrictions like ordinary servos, it is suitable to drive sweeping robot models, automatic sorting devices, and even simple animation props.
In addition, many educational products will also use it, such as car kits for students to learn robot programming. The cost of this kind of servo is not high, and the control method is simple. It can be easily driven with a Micro:bit or Micro:bit. If you want to make some interactive devices, such as a small rotating stage or an automatically rotating display stand, it is also a perfect match.
The biggest fear when choosing a servo is that it won’t move after installation, or it will move too slowly. Torque determines whether it can pull your structure, and speed affects response efficiency. The torque of a 9g servo is usually around 1.5kg·cm, which is enough if you only drive small wheels or light-load structures. But if you want to lift heavy objects, you have to choose a model with higher torque.
In terms of speed, it is common to rotate 60 degrees in 0.1 seconds, but because it is continuous rotation, you are more concerned about the no-load speed, which is generally between 50 and 70 rpm. You can judge this way: if you want the car to go faster, choose a higher speed; if you just want to turn slowly, a lower speed will be more stable. Don't just focus on the parameters. It's best to combine your own load conditions and ask the seller for actual measured data.
Many people are easily confused at first, thinking that all servos can be used universally. In fact, the standard servo controls the angle by PWM signal. If you give it a pulse width, it will turn to the corresponding position and stop. The continuous rotation servo removes the feedback potentiometer and changes it to a mode that can rotate continuously. The PWM signal controls not the angle, but the rotation speed and direction.
In other words, you can use the same control panel to make the servo rotate forward, reverse, accelerate, and decelerate. This is especially friendly for wheeled robots, which is equivalent to directly integrating drive and steering. However, it should be noted that the continuously rotating servo has no position feedback, so it is not suitable for actions that require precise angle control, such as opening and closing the gripper. In this scenario, a standard servo must be used.
In addition to torque and speed, there are several key points you must look at. The first is the working voltage. Many 9g servos are powered by 5V. If you use a 3.7V lithium battery, you may have to choose a wide voltage version. The second is the gear material. Plastic gears are cheap, but they are prone to tooth cleaning after being used for a long time. Metal gears are more expensive, but durable. Especially for projects with heavy loads or frequent reversals, it is recommended to choose metal gears.
Another often overlooked aspect is cable length and connector type. If you want to install it in a car and the cord is too short, you will have to connect an extension cord yourself, which is prone to problems. In addition, some servos use standard DuPont connectors, and some use special plugs. It is best to confirm in advance whether they can be directly plugged into your control board. Taking care of these small details can save a lot of debugging time.
After getting the steering gear, how can you quickly verify your idea? The most direct way is to set up a simple test bench. You can prepare a Uno or Nano, connect the servo power and signal lines, and burn a simple control code, such as making the servo rotate forward for 2 seconds and then reverse for 2 seconds to see if the movement is smooth.
If you want to make a prototype of a car, it is even simpler: the two servos can be used as wheels directly, use universal wheels as supports, add a battery to the control panel, and you can start running in a few minutes. The advantage of this quick verification is that it can detect problems such as structural interference and insufficient power supply in advance, saving you the trouble of discovering that it can’t run after it’s fully installed. Remember, change several speeds and loads during the test to see how the steering gear heats up. This is the reference for real projects.
Even though the servo is small, it can easily break if not used properly. The most common one is overloading. For example, if you keep giving signals when it is stuck, the gears will easily collapse. Therefore, when designing the structure, it is best to leave a little buffer space or add a limit switch. In addition, there is no internal angle limit for the continuous rotation servo. If you don't want it to rotate infinitely, you have to control the rotation time in the program or use a sensor to stop it.
You should also be careful when storing and welding. The shell of the 9g servo is relatively thin, so don't use too much force when disassembling and assembling it. If you frequently plug and unplug cables, it is recommended to use a servo extension cable so that if the connector becomes worn, you can just replace the cable without touching the servo itself. Check the gear regularly for any abnormal noise. If there is any sound, it means that it is time to clean or replace the gear, so that it can work stably in your project for a long time.
Where else do you think this small servo can be cleverly used in your next innovative project to make the product move more attractive? Welcome to chat about your thoughts or share your testing experience in the comment area~
Update Time：2026-03-26
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