Reasons Why Stepper Motors Are Rarely Used in Industrial Robots

The main reasons for the limited use of stepper motors in industrial robots are as follows:

1. Low stepper speed and torque, insufficient for the rated load at the end effector.

2. Low stepper accuracy and prone to missed steps. The serial structure of industrial robots already has accumulated errors; stepper motors further reduce absolute accuracy, making them unsuitable for most industrial applications.

3. Stepper motors rely on pulse frequency for speed regulation, resulting in poor low-speed response and a tendency to stall.

4. High noise levels.

5. Stepper motors cannot achieve closed-loop control, making it impossible to know the position of each axis of the robot; zeroing is required every time the robot is powered on.

However, stepper motors also have advantages: they are inexpensive, and if a reducer is not needed, the cost is even lower. Therefore, they are very suitable for applications where accuracy, load, and noise requirements are not high.