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Published 2026-02-16
Play with theservo: teach you how to control theservomotor step by step
Do you also have such troubles? I see a cool robot project, or I want to add a joint that can swing accurately to my product, but I feel a little scared when I see the words "servomotor" and "." It feels like I have to gnaw a hard nut, programming and circuitry, for fear of accidentally burning the parts. In fact, it is much simpler to move the servo than you think. It is like installing "eyes" and "brain" on a small motor, which can accurately know where to turn. Today, we will talk about it thoroughly and ensure that you can get started after reading it.
To put it simply, servo motors are completely different from the DC motors you usually play with. Ordinary motors will just keep spinning stupidly when plugged in, but servo motors are "thinkers". If you tell it to turn to 90 degrees, it will stop steadily at 90 degrees and not move at all. Behind this lies a set of precision gears and feedback circuits inside it. Its most common "appearance" is that small square box with three wires extending out. The rotating rocker arm usually moves between 0 and 180 degrees. In real life, what is the most suitable thing to use it for? For example, the steering wheel of a smart car, the joints of a robotic arm, or even an automatically swinging cat wand all require it to accurately control the angle.
When it comes to connection, you only need to remember one sentence:Don’t connect the wrong wires. Generally, micro servo motors have three wires, which are brown (or black) negative wire, red positive wire, and orange or white signal wire. The "golden partners" of the connection are: connect the negative wire to the GND pin, the positive wire to the 5V pin, and the most important signal wire should be plugged into a digital pin with a tilde "~", such as the commonly used No. 9 or No. 10 pins. This step is like assigning tasks to three people. The power supply is responsible for the physical work, and the signal line is responsible for transmitting the "turn left, turn right" command.
When you connect the cables, connect to the computer and open the IDE, you will find it so fun. You don't need to be a programming expert, because the "servo control library" has been thoughtfully prepared for you. You only need to write a # at the top of the code, which is equivalent to saying: "Hey, I am going to use the servo next, please be ready." Then, you only need two or three lines of simple code, such as .write(90);, this line of command means "Please turn to the 90-degree position." It's that simple, upload the code, and you will see the servo's rocker arm "swish" to the center.
If you just let it jump directly from 0 degrees to 180 degrees, you will find that its movement is very stiff, like being kicked. How to make it rotate gracefully like a robot arm? There is a little trick here, which is to use a loop. You can use a for loop to increase the angle little by little. For example, start from 0 degrees, increase by 1 degree each time, and wait for 15 milliseconds after each increase. The code is written as for (pos = 0; pos
There are always minor setbacks when playing. Sometimes you will find that the servo keeps shaking, or you want it to turn 90 degrees, but it only turns to 85 degrees and then stops. Don't immediately suspect that the servo is broken, it's most likely due to insufficient power supply. The 5V output current is limited. When you use a slightly larger servo, or bring two servos at the same time, the current is like water in a water pipe. If the water pressure is not enough, the motor will not rotate and start to shake. At this time, you need to prepare a separate external power supply for the servo, such as several batteries. Connect the positive and negative wires of the servo to the battery, leaving only the signal wire. This way the problem is often solved.
There are so many servos on the market, what should you do if you are confused? You only need to look at three parameters. The first istorque, which determines how powerful the servo is. If you want to use it to lift a heavy object, you have to choose one with greater torque. The second isspeed, which determines whether it turns fast or not. The third one isthe working voltage. For most small maker projects and product prototypes, a standard 9g micro servo is enough, cheap and easy to use. If you want to make a feeder that opens the door automatically, you have to choose one with metal gears and strong strength.
Seeing this, do you think that controlling the steering gear is not so mysterious? You have actually mastered the core step of making objects "alive". Next, you might as well open your tool box, connect a servo with your own hands, and let it turn.
When you are making a small invention, what do you most want to use a servo to control? Is it a camera gimbal, a robot hand, or something more interesting? Welcome to share your ideas in the comment area, and let’s communicate and create sparks together. If you find the article useful, don’t forget to give it a like and share it with your maker friends!
Update Time：2026-02-16
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