A drug delivery device comprising: a housing; a cylindrical member rotatably supported within the housing; and a plurality of sensors; wherein: the outer surface of the cylindrical member is provided with a single track, the track forming an encoder and having a plurality of first track segments and a plurality of second track segments arranged along the length of the track which are respectively capable of inducing first and second responses in the sensors; and in each rotational position of the cylindrical member relative to the housing at least one different first track segment is capable of inducing a first response in at least one said sensor, thereby enabling the rotational position of the cylindrical member relative to the housing to be determined.

A vehicle steering system comprises: a motor assembly operably coupled to a steering rack, the motor assembly comprising a motor having a rotor and a motor position sensor configured to sense a rotor angle of the motor in a single-turn range; and a rotary-to-linear conversion mechanism operably coupled between the motor assembly and the steering rack, the rotary-to-linear conversion mechanism comprising a rotor operably coupled to the rotor of the motor. A processor calculates an absolute angular position of the pinion in a full-turn range of rotation of the pinion based on the sensed rotor angle of the motor and a pinion angle sensed by a pinion angle sensor in a single-turn range, or based on the sensed rotor angle of the motor and an angle of the rotor of the rotary-to-linear conversion mechanism sensed by an angular position sensor in the single-turn range.

Cable-actuated position sensors are described that employ multiple block and tackle arrangements to measure displacement of a draw wire or flexible cable. The disclosed sensors are relatively small and inexpensive. The disclosed sensors may also be used as part of a servo motor, or in conjunction with gear motors to provide positional information for operation of the gear motor.

Cable-actuated position sensors are described that employ multiple block and tackle arrangements to measure displacement of a draw wire or flexible cable. The disclosed sensors are relatively small and inexpensive. The disclosed sensors may also be used as part of a servo motor, or in conjunction with gear motors to provide positional information for operation of the gear motor.

A rotor-hub flap-measurement system includes a rotor hub operable to flap relative to a main-rotor axis, a flap-linkage arm, a first end of the flap-linkage arm rotatably coupled to the rotor hub, the flap-linkage arm responsive to flapping of the rotor hub, and a magneto-resistive sensor system rotatably coupled to a second end of the flap-linkage arm and responsive to movement of the flap-linkage arm.

A rotation detection sensor is disposed to face an outer peripheral part of a signal rotor, and outputs a detection signal corresponding to a position of the outer peripheral part with the rotation of the signal rotor. The rotation detection sensor detects a rotation reference position with the detection of switching from projections to a missing tooth part on the basis of a gap to the signal rotor, and detects switching from the missing tooth part to the projections to output a rotation reference position signal indicative of position information on the rotation reference position at timing of the detection. An ECU receives the detection signal and the rotation reference position signal from the rotation detection sensor, and acquires the rotation reference position on the basis of the rotation reference position signal.

Cable-actuated position sensors are described that employ multiple block and tackle arrangements to measure displacement of a draw wire or flexible cable. The disclosed sensors are relatively small and inexpensive. The disclosed sensors may also be used as part of a servo motor, or in conjunction with gear motors to provide positional information for operation of the gear motor.

One object is to calculate the position of a rod of a linear actuator with a high precision. The linear actuator includes a rod capable of moving in an axial direction relative to a housing. The rod is moved by rotation of an output shaft of a motor. A position sensor for sensing the relative position of the rod relative to a preset reference position is provided in the housing. A rotation sensor for sensing the rotation angle of the output shaft of the motor is provided in the vicinity of the motor. The linear actuator includes a position calculating unit for calculating the position of the rod based on a position sensing value of the position sensor and a rotation angle sensing value of the rotation sensor.

An absolute position sensor includes a first gear having a plurality of teeth, a rotational position sensor operatively coupled to the first gear to be configured to detect a rotational position of the first gear, and a second gear including a spiral tooth engaged with the plurality of teeth of the first gear to rotate with the first gear, and having a first end with a first distance from a center of the second gear, and an opposite second end with a second distance from the center of the second gear, the second distance being less than the first distance.

An electronic device includes a first housing, a second housing slidably coupled to the first housing, a rollable display configured to be enlarged or reduced based on a movement of the second housing, a rack gear disposed on the second housing, a pinion gear driven in engagement with the rack gear and including a plurality of teeth, an actuator configured to rotate the pinion gear and coupled with the pinion gear by a shaft, a first magnet surrounding at least part of the shaft, and spaced apart from the pinion gear along the shaft, and a hall sensor spaced apart from the pinion gear in direction perpendicular to the shaft, and a processor, wherein the processor is configured to obtain data related to a change in the magnetic force using the hall sensor and identify a rotating angle of the pinion gear based on the data related to a change in the magnetic force.