Variable torque control of a stepper motor

摘要

A stepper motor may be controlled by a controller to provide extended revolution of a motor shaft while operating in a first mode and to allow a user to manually intervene with an intended position or rotation of the motor shaft while operating in a second mode. In some embodiments, the controller may adjust a torque applied to the stepper mode during operation of the stepper motor. The controller may reduce a torque applied by the stepper motor to a lower torque while the user intervenes with the intended position or rotation of the motor and increase the torque to a holding torque after the user intervention has ended. Thus, the controller may dynamically adjust a torque of the stepper motor in response to detection of the user intervention.

主权项

1. A stepper motor assembly comprising:
a stepper motor having at least a stator and a motor shaft, the motor shaft to rotate relative to the stator to a control position or to maintain the control position; an encoder to detect rotation of the motor shaft relative to the stator and output position feedback in response to the detected rotation; a driver to cause the motor shaft to rotate relative to the stator to the control position or to maintain the control position; and a controller configured to:
receive the position feedback;provide a signal to the driver to cause movement of the motor shaft;determine occurrence of intervention with movement of the motor shaft relative to the stator based at least in part on the position feedback; and;decrease at least temporarily, a torque applied between the motor shaft and the stator during at least a portion of the occurrence of the intervention.