Wanting to understand more about stepper motors and their control - have a look below at our run down of the key terms used in relation to stepper motors.
Stepper Motor: An electromechanical device that divides a full rotation into a number of equal steps, allowing for precise control of angular position.
Step Angle: The angle by which the motor shaft moves in response to a single step command. It is typically specified in degrees per step.
Microstepping: A technique for increasing the resolution of a stepper motor by dividing each full step into smaller steps using precise control of the current in the motor windings.
Bipolar Stepper Motor: A type of stepper motor with two coils and requires current to be driven in both directions through the coils, typically needing an H-bridge circuit for control.
Unipolar Stepper Motor: A type of stepper motor with a center-tapped winding per phase, allowing for simpler control by switching the direction of current flow through only half of the winding at a time.
Full Step Mode: A mode of operation where the motor moves by one full step for each pulse received, typically providing lower resolution but higher torque.
Half Step Mode: A mode of operation where the motor alternates between full steps and half steps, providing a compromise between resolution and torque.
Current Control: A method of controlling the current through the motor windings to regulate torque and reduce power dissipation.
Chopper Drive: A type of current control method that uses pulse width modulation (PWM) to regulate the current through the motor windings, improving efficiency and performance.
Holding Torque: The maximum torque that a stepper motor can hold when the windings are energized but the shaft is not moving.
Detent Torque: The torque that is produced by the motor's internal magnetic structure when the windings are not energized, providing a small amount of resistance to shaft movement.
Hybrid Stepper Motor: A type of stepper motor that combines features of both permanent magnet and variable reluctance stepper motors, offering improved performance and accuracy.
Permanent Magnet Stepper Motor: A type of stepper motor that uses permanent magnets in the rotor to create a magnetic field, typically offering higher torque at low speeds.
Variable Reluctance Stepper Motor: A type of stepper motor that operates by changing the reluctance of the magnetic path through the motor, typically offering higher speeds but lower torque.
Driver: An electronic device that controls the current flow through the motor windings to achieve the desired stepping motion.
Indexer: A device that converts step and direction inputs into the appropriate signals to control the motor driver.
Step Sequence: The specific order in which the windings are energized to produce the desired motion, such as full step, half step, or microstepping sequences.
Backlash: The small amount of play or slop between the motor's mechanical components, affecting the accuracy of positioning.
Stepper Motor Controller: An electronic device or software that generates step pulses and direction signals to control the motor driver.
Pulse Rate: The frequency of the step pulses provided to the motor, determining the speed of the motor's rotation.
Rotor Inertia: The resistance of the motor's rotor to changes in speed, affecting the motor's acceleration and deceleration characteristics.
Lead Screw: A screw mechanism often used with stepper motors to convert rotational motion into linear motion with precise control.
Stepper Resolution: The smallest increment of movement that a stepper motor can achieve, typically determined by the step angle and any microstepping used.
Slew Rate: The maximum rate at which the stepper motor can be accelerated or decelerated without losing steps, typically limited by the motor's torque and inertia.
Thermal Management: The practice of managing heat dissipation in the motor and driver to prevent overheating and ensure reliable operation.
Stepper Motor Torque Curve: A graph showing the relationship between torque and speed for a stepper motor, illustrating how torque decreases with increasing speed.
Phase: A term referring to each winding in the stepper motor; stepper motors are typically classified as bipolar (two phases) or unipolar (four or five phases).
Home Position: A predefined reference position used as a starting point for motion control, often established using a limit switch or sensor.
Feedback: The process of using sensors to monitor the position or speed of the motor shaft and adjust the control signals accordingly, typically used in closed-loop stepper motor systems.
Open-Loop Control: A control method where the step pulses are sent to the motor without feedback, assuming the motor will move as commanded.
Closed-Loop Control: A control method that uses feedback to monitor and adjust the motor's position and speed, improving accuracy and reliability.