The ​stepper motor encoder​, also known as a motor feedback device, is a device used to measure the rotation position and speed of a stepper motor. It usually consists of a photoelectric sensor and a code disk. When the stepper motor rotates, the code disk in the encoder rotates, and the photoelectric sensor converts the photoelectric signal into an electrical signal, which is then processed by the electronic circuit to output the corresponding rotation position and speed information.

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2.Why does the stepper motor need an encoder?

1. Improve accuracy and performance

The use of encoders can improve the rotation accuracy and performance of stepper motors. Since the positioning method of stepper motors is usually through open-loop control, the motor will rotate a certain angle according to the drive signal, but the actual rotation angle may be due to factors such as load and wear. The encoder can feedback the rotation position and speed information in real time, so that the control system can correct the error in time and improve the motion accuracy and control performance of the stepper motor.

2. Reliability and stability

The stepper motor encoder has its own feedback function, so when dealing with abnormal situations such as sudden loads and power fluctuations, it can detect the actual operating status of the motor in time, making the system more stable and reliable.

Stepper motor encoders are usually divided into two types: absolute encoders and incremental encoders.

1. Absolute encoder

Absolute encoders can accurately locate the angle value of the motor. Even after the motor is powered off and restarted, the system can accurately identify the current position of the motor without the need for a reset operation. Therefore, they are usually used in situations where the motor control accuracy is required to be high.

2. Incremental encoder

Incremental encoders can measure the relative displacement and speed value of the motor rotation without the need for a reset operation. They are usually used in situations where the motor control accuracy is required to be low.

The function of the stepper motor encoder is to provide precise positioning and feedback information for the control system, which can not only improve the accuracy and performance of the stepper motor, but also improve the reliability and stability of the system. According to the actual control requirements, different types of encoders can be selected to achieve control of the stepper motor.

Source:https://plaza.rakuten.co.jp/yixing/diary/202407100000/