A power tool includes a motor having an output shaft, an extensible member driven by the motor, a working assembly movable in response to contact with a distal end of the extensible member, a first sensor configured to detect a home position of the extensible member, a second sensor configured to detect rotation of the motor output shaft, and a controller in electrical communication with the first and second sensors. The controller is configured to drive the motor output shaft in a first rotational direction a predetermined number of revolutions counted by the second sensor, thereby displacing the extensible member from the home position. The controller is also configured to drive the motor output shaft in an opposite, second rotational direction to thereby return the extensible member until the home position is detected by the first sensor.

A servo motor controller includes: a servo motor; a driven member which is driven by the servo motor and in which a load acting on a drive axis is varied depending on the position of the driven member; a position detection portion and a speed detection portion for the driven member; and a motor control portion, where the motor control portion includes: a position control portion which calculates a speed command based on a positional error between a position command for the driven member and the position FB; a speed control portion which calculates a torque command by multiplying a speed error between the speed command and the speed FB by a speed gain and/or adding a torque offset to the speed error; and a change portion which changes at least one of the speed gain and the torque offset according to the position of the driven member.

An example method for controlling a carriage of a printing device is described. In one implementation, a target velocity value that satisfies a sharpness threshold is filtered by a processor resource of the printing device, a feed forward term is generated using a continuous model applied to the filtered velocity input using a plurality of electromechanical parameters, a feedback term is generated based on a difference between an expected pulse-width modulation (PWM) profile and an actual PWM profile, and a voltage to be provided to a motor of the carriage is adjusted based on the feed forward term and the feedback term.

A power tool includes a motor having an output shaft, an extensible member driven by the motor, a working assembly movable in response to contact with a distal end of the extensible member, a first sensor configured to detect a home position of the extensible member, a second sensor configured to detect rotation of the motor output shaft, and a controller in electrical communication with the first and second sensors. The controller is configured to drive the motor output shaft in a first rotational direction a predetermined number of revolutions counted by the second sensor, thereby displacing the extensible member from the home position. The controller is also configured to drive the motor output shaft in an opposite, second rotational direction to thereby return the extensible member until the home position is detected by the first sensor.

An example method for controlling a carriage of a printing device is described. In one implementation, a target velocity value that satisfies a sharpness threshold is filtered by a processor resource of the printing device, a feed forward term is generated using a continuous model applied to the filtered velocity input using a plurality of electromechanical parameters, a feedback term is generated based on a difference between an expected pulse-width modulation (PWM) profile and an actual PWM profile, and a voltage to be provided to a motor of the carriage is adjusted based on the feed forward term and the feedback term.