Teach You Step By Step How To Select And Debug The Servo Steering Gear Controller. Read This Article.

What’s the most troublesome thing about product innovation? The idea is obviously very good, but the result is that theservocontrol is stuck, the movement is shaking like "Parkinson", or no matter how much adjustment is made, the desired angle cannot be achieved. Today we will talk about the "behind-the-scenes commander" oftheservosteering controllerto help you thoroughly understand this little thing from getting started to getting started.

## Why useservosteering controller?

Many friends who have just started working on projects like to directly use the PWM of the development board to drive the servo. This method is fine for small servos. Once the torque is large and the number is large, the development board will be "stressed" instantly. Not only will the response be slow, but the board will be burned due to insufficient current.The servo servo controlleris like a professional "plug-in brain". It is responsible for processing the signals and power of the servo. It takes care of complex timing calculations and power supply issues, allowing your main control chip to easily handle more complex logic.

For example, if you want to make a six-legged robot, it will have 18 servos. If you rely on the development board to control it directly, the program is so complicated that it makes you want to cry. Moreover, if there are too many servos, the power supply will go on strike if the power is slightly unstable. With the controller, it's easy. You only need to tell it "turn the No. 3 servo to 90 degrees" and it will do the rest by itself. This is the charm of professional tools, which standardize complex things and allow you to focus on creativity.

##How to chooseservo steering controller

There are all kinds of controllers on the market, ranging from tens of dollars to thousands of dollars. How do you choose without stepping on the trap? ️ First look at the number of channels, that is, how many servos can be controlled at the same time. For robotic arms, 4-6 may be enough, but for bionic robots or multi-axis platforms, it is recommended to choose 16 or even 32 channels. Don’t hold on to the idea of “buy a small one first, and then upgrade later if you don’t have enough”. Replacing the controller halfway through the project, wiring and debugging will make you doubt your life.

️ Secondly, look at the communication interface, which is directly related to how you "manage" it. The most commonly used ones are the serial port (UART) and I2C. For simple projects, the serial port is enough. One line can send instructions, and you can learn and use them immediately. If your main control board interface is tight, or you need to place the controller farther away, choose one with RS485 or CAN bus, which has strong anti-interference ability and long transmission distance. Remember one principle: first determine how your main control board will talk to it, and then find a matching controller.

##How to wirethe servo servo controller

The wiring area is a high-risk area for novices to overturn. Let's take it apart and see clearly. 1. Power cord, this is the most important thing! The instantaneous current of the steering gear is very large, especially when multiple motors are operating at the same time. Don't take the power directly from the 5V of the main control board to save trouble, as it will most likely restart directly. The correct way is to supply power to the controller separately, such as using a 6V-7.4V battery pack, and then share the ground, that is, the GND of the controller should be connected to the GND of the main control board, so as to ensure signal stability.

2. Signal line, this is simple. The signal input pin (TX/RX or SCL/SDA) of the controller is connected to the corresponding pin of the main control board, and the servo plug is directly connected to the output port of the controller. Here's a little tip: power off all equipment before wiring, and then power on again after wiring. Developing this habit can save you several controller "lives". Don’t rush to write code after connecting the wires. After powering on, manually test whether each servo can return to its normal position. This step can eliminate 90% of hardware problems.

## How to make the servo movement smoother

Do you often encounter the servo "clicking" or making jerky movements? This is probably because the speed and acceleration are not set properly. Many controllers support "time control" mode, which means you directly tell it "go from the current position to 90 degrees and complete the journey in 2 seconds." In this way, the servo will automatically calculate the intermediate trajectory and achieve uniform motion, which looks very smooth. For example, if you make a nodding action and give a quick instruction directly, the effect is like a chicken pecking at rice; but if you give a slow transition of 1.5 seconds, you will instantly have the advanced feeling of "nodding calmly".

There is another small detail, which is the parameter "maintaining torque after reaching the position". If your mechanical structure itself has a gravity load, such as the shoulder joint of a robotic arm, the servo needs to continuously output torque to maintain the posture after the servo is in place. At this time, you can set the "holding torque" of each servo individually, which can not only prevent sagging due to gravity, but also save power than always outputting full torque. Once you adjust these detailed parameters, your work will be just one step away from "dynamic" to "smart".

## What to do if you encounter problems during debugging

Don't panic if you encounter problems, we will troubleshoot according to the process. First thing, check the power supply. Use a multimeter to measure the voltage at the input of the controller. Many strange jitters are caused by the power supply voltage drop. For example, if the battery is dead and the voltage drops below 4V upon operation, the servo will definitely move randomly. The second thing is to look at the indicator light. A normal controller has a power light after power is turned on, and the signal light will flash when a command is received. If the lights are not on, check the power supply and wiring first; if the power supply is normal but there is no response, it is most likely that the communication protocol is not correct, such as the baud rate is set wrong.

What should I do if the movements are normal but the position is incorrect? At this time, it is necessary to calibrate the center position and angle range of the servo. Most servos are 90 degrees at a 1.5ms pulse, but there will be slight deviations among different brands. You can use the "manual mode" that comes with the controller to first find its true "median" value and record it, and then set the maximum and minimum angles. Many advanced controllers support storing calibration parameters directly into the chip, so there is no need to re-adjust the main control board once and for all.

## How to get started quickly

It’s easy to understand on paper, but I’ll give you the quickest way to get started: first spend dozens of dollars to buy a 16-channel servo controller with a USB interface. This kind of board can be controlled directly with computer software, without writing code. You first plug in a few servos, drag the sliders in the software, and see with your own eyes how the process of "sending commands - executing actions" is implemented. It only takes half an hour to understand the relationship between the core concepts of "angle value", "speed" and "delay".

Find a communication protocol document for the controller and try sending a few commands using a programming environment you are familiar with. For example, using the serial port library, write a loop to make the servo swing back and forth. When you see the code successfully making the machinery in the physical world move, you will feel that all the trouble is worth it. Once you have mastered these basic operations, whether you are making a robot, an automatic feeder or a smart home device, you will no longer feel that the steering gear control is a stumbling block.

After talking so much, from model selection to wiring, from parameter adjustment to debugging, the core is to help you make "controlling the servo" simple and reliable. Does the product you are currently conceiving include a joint that requires "precise movement"? You might as well pick up a controller now and conquer this key link.