The disclosure relates to a drug delivery device having a drive unit includes a stator comprising a plurality of coils consecutively arranged in an axial direction, and an armature axially movable within the stator, the armature including a number of magnets and pole shoes consecutively arranged in the axial direction. A respective pole shoe is arranged between respectively neighbouring magnets. At least one axial end of the armature comprises a terminal pole shoe.

A positional variance based distance sensing apparatus has a physical marker that changes its position (either rotational or linear) in accordance to the distance of an object from the sensor. This positional change can be used to sense the distance using touch by humans. This positional variance can also be used to control triggers like switches, leavers, and steering based controllers.

Excitation position is changed in accordance with an external clock. The state of a full bridge circuit including four transistors connected to a coil of a stepping motor, is controlled in accordance with the excitation position. At the time of transition from the excitation position at which coil current that flows in the coil is nonzero to the excitation position at which the coil current is zero, a switch is made to (i) the inverse state where the on or off state of each of the four transistors before the transition is inverted, and then a switch is made to (ii) the off state where all the four transistors are off.

A control device for a stepper motor drives in a 1-2-phase excitation method in response to an input of a drive signal. The control device includes a control signal generating unit and a drive signal generating unit. The control signal generating unit generates a pulsed control signal. The drive signal generating unit generates the drive signal for rotating by a predetermined step angle every time the control signal is input. The predetermined step angle is a half of a step angle of a 2-phase excitation method. The control signal generating unit configures a higher pulse rate of a first to an n-th (n is an integer equal to or more than 2 and equal to or less than 3) control signals in an activation period of the stepper motor than a pulse rate of the control signals following the n-th control signal.

A DC motor control device includes a communication circuit configured to receive a control command specifying a target rotation amount for a DC motor, a sensor interface configured to receive a detection signal from a rotational angle sensor that outputs the detection signal every time the DC motor rotates by a certain rotational angle, a step counter that outputs a count signal every time the detection signal has been received a certain number of times, a controller that, based on the number of times the count signal received, determines a step count representing the total amount of rotation, and generates a control signal that controls the DC motor in accordance with the step count and the target rotation amount, and a drive signal generation circuit that generates a drive signal that rotates the DC motor in accordance with the control signal.

A motor controller that includes a processing device and a drive circuit. The drive circuit may include a plurality of switches, a motor winding, and a current sensor coupled together in an H-bridge configuration. The processing device is configured to cause a drive current to drive through the motor winding for a minimum amount of time. The processing device is also configured to compare the current through the current sensor to a threshold value at the minimum amount of time. The processing device is also configured to, based on the current being at or above the threshold value at the minimum amount of time, stop the drive current for an off period of time and cause a first decay of the current for a first percentage of the off period of time and a first slow decay for a second percentage of the off period of time.

A device for forming and applying accessory elements to a continuous band of absorbent material, includes a unit for feeding a continuous strip to a conveyor roller, a unit for cutting the strip in a continuous and alternating succession of first and second pieces, a first and a second roller rotating about respective axes parallel to the first direction, each including a movement device acting along a circumferential direction around the respective axis and configured for imparting to each unit a respective motion between positions for picking up and releasing the pieces. A unit for applying a pair of pieces to the band is equipped with a separating unit equipped with a spacer device for moving first and/or second carriages along a separating direction between closed and far axial positions, wherein the spacer device includes a plurality of linear actuators each associated with a respective first carriage.

Aspects of the invention provide methods and systems for moving a plurality of moveable stages relative to a stator. The stator comprises a plurality of coils shaped to provide pluralities of coil trace groups where each coil trace group comprises a corresponding plurality of generally linearly elongated coil traces which extend across a stator tile. Each moveable stage comprises a plurality of magnet arrays. Methods and apparatus are provided for moving the moveable stages relative to the stator, where a magnet array from a first moveable stage and a magnet array from a second moveable stage both overlap a shared group of coil traces. For at least a portion of the time that the magnet arrays from the first and second moveable stages overlap the shared group of coil traces, currents are controllably driven in the shared coil trace group based on the positions of both the first and second moveable stages. The positions of the first and second moveable stages may be ascertained by feedback.

Aspects of the invention provide methods and systems for moving a plurality of moveable stages relative to a stator. The stator comprises a plurality of coils shaped to provide pluralities of coil trace groups where each coil trace group comprises a corresponding plurality of generally linearly elongated coil traces which extend across a stator tile. Each moveable stage comprises a plurality of magnet arrays. Methods and apparatus are provided for moving the moveable stages relative to the stator, where a magnet array from a first moveable stage and a magnet array from a second moveable stage both overlap a shared group of coil traces. For at least a portion of the time that the magnet arrays from the first and second moveable stages overlap the shared group of coil traces, currents are controllably driven in the shared coil trace group based on the positions of both the first and second moveable stages. The positions of the first and second moveable stages may be ascertained by feedback.

A method of controlling a dual-wound synchronous machine includes: determining positive and negative virtual half-motor current commands based on first and a second motor current commands associated with the first and second winding sets; calculating positive and negative final voltage commands based on the virtual half-motor current commands, and using first and second sets of gain factors; and commanding, based on the final voltage commands, inverters to apply an output voltage to each of two winding sets and thereby causing output currents to be generated herein. The output currents each have a d- and q-axis components, and at least one of the first set of gain factors and the second set of gain factors is configured to cause the d-axis component and the q-axis component of the first output current to be decoupled from variations of d-axis and q-axis components of the second output current.