Abstract of Closed-Loop Control Method for Stepper Motors: What are the advantages of Suzhou in building a first-class mold industry base in Asia? Typical Q&A on CNC Machining The latest progress and development trends in the field of surface engineering Ten major development trends in the hardware mold market Analysis of negative pressure chip removal and chip breaking in hole machining A complete guide to advanced AutoCAD skills Programming source code for machining external tapered threads Analysis of award-winning projects of the China Machinery Industry Science and Technology Award Classification of CNC machine tools Interface between cutting tools and machine tools Introduction to CNC machining and coordinate systems Research and application of bidirectional integration technology of 3D CAD and PDM systems Application and market value of five-axis linkage CNC systems Ningjiang Group's automatic lathe programming software system passed review Weichai Power launched the energy-saving bus special engine Pilz Application of safety products on CNC machine tools Improve the efficiency and stability of cast iron turning CNC machining source code for shaft parts 1 Current status and future market demand of China's cutting machine tool industry According to the survey of the Incremental Motion Control Association, closed-loop control of stepper motors can adopt various different methods, including step counting (or step verification), sensorless back EMF detection and sensor feedback full servo control. Step verification is the simplest form of position control, using a low-resolution photoelectric encoder to count the number of steps moved. A simple circuit compares the commanded number of steps with the measured number to verify that the stepper motor has moved to the designated position. According to a survey by the Incremental Motion Control Association, closed-loop control of stepper motors can employ various methods, including step counting (or step verification), sensorless back EMF detection, and sensor-feedback full servo control. Step verification is the simplest form of position control, using a low-resolution photoelectric encoder to count the number of steps moved. A simple circuit compares the commanded number of steps with the measured number of steps to verify that the stepper motor has moved to the designated position. Back EMF is a sensorless detection method that uses the back EMF signal of the stepper motor to measure and control speed. According to Dan Jones, president of the Incremental Motion Control Association, when the speed is too low so that the back EMF voltage falls below a detectable level, closed-loop control switches to open-loop control before completing the final positioning motion. Full servo refers to consistently using encoders, resolvers, or other feedback devices for more precise control of the stepper motor's position and torque. Several suppliers worldwide have begun offering such products. Parker Hannifin complements back-EMF control methods with active damping and encoderless stall detection. Stepper motor drivers monitor and measure voltage and current information from the motor windings, using this information to improve stepper motor control. Active damping uses this information to suppress speed oscillations, allowing the motor to output more usable torque—rather than wasting torque on mechanical vibrations. Encoderless stall detection uses this information to detect step loss, a serious problem for open-loop control.