Abstract: This disclosure enables an assembly for driving an arm of a windshield wiper of a vehicle. The assembly includes a support structure in a housing that is secured against rotation relative to the housing. The support structure has an opening with a bearing surface, where the opening is configured to receive a boss of a worm wheel such that the bearing surface faces the boss of the worm wheel.

Abstract: In one aspect, an angle sensor includes magnetic-field sensing elements that include a first pair, a second pair, a third pair and a fourth pair of magnetic-field sensing elements; and processing circuitry configured to determine an angle of a rotating ring magnetic having a plurality of North-South pole pairs each having a unique period length. The processing circuitry includes a first bridge formed from the first and second pairs of magnetic-field sensing elements and a second bridge formed from the third and fourth pairs of magnetic-field sensing elements. The angle includes a value from 0° to 360°. The first, second, third and fourth pairs of magnetic-field sensing elements are each disposed on a first axis. The first, second, third and fourth pairs of magnetic-field sensing elements each have a sensitivity in a first direction along the first axis. The angle sensor is formed on a single die.

Abstract: An unmanned aerial vehicle (UAV) includes a central body, one or more propulsion units configured to propel the UAV through the air, and a carrier supported by the central body. The carrier is configured to support and permit a payload to move relative to the central body. The carrier includes a guide coupled to the central body and a gimbal configured to couple a payload to the guide. The gimbal is further configured to flip the payload above the carrier when the payload is at a top end of the guide relative to the central body.

Abstract: An electronic sensor includes a signal generator configured to output a first excitation signal and a second excitation signal and a variable differential transformer connected to the signal generator to receive the first excitation signal and the second excitation signal. The variable differential transformer may include a primary coil, a first secondary coil connected to the signal generator, a second secondary coil connected to the signal generator, and a core disposed at least partially in a magnetic field generated via the first secondary coil and the second secondary coil and the first excitation signal and the second excitation signal. A phase of an output signal of the primary coil corresponds to a position of the core.

Abstract: A magnetic position detecting device and a method for detecting a magnetic position are provided. An induced voltage is generated by changing a position between a pattern of an inductive ruler and an alternating magnetic field of an exciting element. A position of the exciting element is resolved by a technical means of voltage resolution for positions.

Abstract: A pulse-induction displacement transducer comprising at least one coil component (100,150), at least one target (112,174), and pulse induction circuitry (102,152} constructed and arranged to cause a pulse of electrical current to pass through the said at least one coil component (100,150). The pulse ends abruptly. Subsequently, the electrical current passing through the said at least one coil component (100,150), or the voltage across it, is measured at a time when any electrical current through or voltage across the said at least one coil component (100, 150) would have died away in. the absence of a target. This provides an indication of the relative position between the target (112,174) and the said at least one coil component (100, 150). The said at least one coil component (100,150) comprises a first terminal portion (108,158), a first coil part (104,152) connected directly or indirectly to the said first terminal portion (108,158) and wound in one sense.

Abstract: A rotary encoder includes a control part having a storage section storing a plurality of parameters regarding error signal components at a reference rotation speed, the error signal components respectively being superposed on an “A”-phase signal and a “B”-phase signal in proportion to a rotation speed of a rotor body, and a rotation speed calculation section structured to measure a reception interval of a requirement signal and calculate a current rotation speed of the rotor body. The control part is structured to convert a parameter stored in the storage section to a value at the current rotation speed based on a ratio between the reference rotation speed and the current rotation speed, correction processing correcting the “A”-phase signal and the “B”-phase signal is executed based on the value converted, and the rotation position of the rotor body is calculated by using a corrected “A”-phase signal and a corrected “B”-phase signal.

Abstract: A device is configured to determine a relative deflection of two transmitter elements by a sensor element. The transmitter elements are arranged at the sensor element. The deflection of the transmitter elements with respect to one another at the sensor element can be determined based on a degree of overlap of conductive regions of the transmitter elements by the sensor element.

Abstract: A position detection apparatus is provided which eliminates the necessity of space to affix a scale to a track member. A track member of a motion guide apparatus is provided with a through hole into which a fastening member to fasten the track member to a base can be inserted. A carriage that is movably assembled to the track member via a rolling element is provided with magnets generating a magnetic field toward the track member. Magnetic sensors that detect a change in the magnetic fields of the magnets with the travel of the magnets relative to the track member are placed within the magnetic fields of the magnets.

Abstract: A thermal printer with head elements enables accurately determining the state of deterioration of the head elements, and minimizing the amount of stored data. A printing device has a thermal head having multiple head elements; a voltage application circuit configured to apply a printing voltage and an inspection voltage to the head elements; a head controller configured to control the thermal head and the voltage application circuit; and data storage configured to store a conversion table relationally storing a divided voltage and a resistance of the head elements. At a specific timing, the head controller applies the inspection voltage to the head elements by the voltage application circuit, measures the divided voltage of the head elements, converts the measured divided voltage to resistance based on the conversion table, acquires deterioration information based on the converted resistance, and stores the deterioration information in the data storage.

Abstract: A method that includes: providing a structure that is movable along a first axis; coupling a sensor assembly to the structure, the sensor assembly comprising first and second eddy current sensors and first and second targets that are mounted to the structure for movement along the first axis; sensing the first target with the first eddy current sensor and responsively generating a first sensor signal; sensing the second target with the second eddy current sensor and responsively generating a second sensor signal; and using the first and second sensor signals to determine a location of the structure along the first axis in a manner that is insensitive to coordinated movement of the first and second targets along a second axis that is perpendicular to the first axis and a third axis that is perpendicular to both the first and second axes.

Abstract: A position sensor for sensing whether a rotatable element is in at least a first rotational position or a second rotational position is provided. A rotor is configured to be coupled to the rotatable element for rotation therewith, and is constructed at least partially of a magnetically permeable material and includes a first rotor pole. A stator is non-rotationally mounted, is constructed at least partially of a magnetically permeable material, is spaced apart from the rotor, and comprises a first main pole and a first stealer pole. The first main pole and the first stealer pole are spaced radially apart from each other. A magnet is non-rotationally disposed adjacent to the stator and is spaced apart from the rotor. A first magnetic sensor is non-rotationally mounted between the stator and the rotor, is disposed adjacent the first main pole, and is radially offset from the first stealer pole.

Abstract: An electric hand power tool includes a cylindrical device section, a control element displaceable about the cylindrical device section, and an electric scanning device disposed at the device section and configured to determine a rotary position of the control element. The scanning device is configured to optically scan the rotary position.

Abstract: A relative rotational angular displacement detection device includes a pair of rotatable members rotatable relative to each other in a circumferential direction. A permanent magnet is attached to one of the rotatable members and includes magnetic poles magnetized in an axial direction of the axis of rotation and arranged to alternate in polarity in the circumferential direction. A magnetic flux guiding ring includes an annular ring body attached to the other of the rotatable members and is arranged coaxially with the axis of rotation, and a plurality of protruding portions each having a circumferential width smaller than the circumferential width of the magnetic pole. A magnetic detection unit is configured to detect magnetic fluxes of the ring body of the magnetic flux guiding ring. The magnetic flux guiding ring is magnetized depending on the positions of the protruding portions relative to the positions of the magnetic poles.

Abstract: A valve actuator having a drive shaft, which, in use, is configured to adjust a valve between an open position and a closed position, an AC induction motor for driving the drive shaft a contactless position sensor configured to, in use, output a signal representing an angular position of the drive shaft or the valve, and a controller configured to control the AC motor in accordance with the signal output by position sensor.

Abstract: A method and apparatus for controlling operation of an electric motor. A controller is configured to identify a position of a disc relative to a plate with coils physically associated with the plate. The controller is further configured to control a current sent to the coils based on the position of a disc. The disc is configured to move such that a closest point between the disc and the plate changes along a periphery of the disc.

Abstract: The position detecting apparatus includes a comparing part that compares the value of the digital signal output from the AD converter and a reference value that is based on a preset reference amplitude at the timings and outputs a control signal responsive to a result of the comparison. The position detecting apparatus includes an amplitude controlling part that controls amplification factors of the first amplifier and the second amplifier in such a manner that the value of the digital signal output from the AD converter comes closer to the reference value in response to the control signal output from the comparing part.

Abstract: The present invention is directed to a method of estimating a motor rotation angle that does not affect precision of a detected angle of a crank angle sensor, which is an alternative sensor, when abnormality occurs in a resolver and a peripheral circuit, and performing a motor control without failure of an inverter or peripheral device. A vehicle system includes a motor, a resolver detecting a rotor rotation angle of the motor, a motor control circuit controlling the motor based on information on rotor rotation angle and torque command value, an engine connected to the motor through a crankshaft, and a crankshaft sensor detecting revolutions of the crankshaft, in which the motor control circuit estimates rotor rotation angle based on a variation rate of the number of revolutions of the crankshaft when abnormality of the resolver is detected, and performs a weak field control based on estimated rotor rotation angle.

Abstract: An exemplary stage apparatus has a motor, stage, and position-measuring device. The motor has a planar stator and moving-coil mover (planar motor). The stator is a checkerboard magnet array extending in an x-y plane and producing a magnetic field having a field period of 2? in a u-v coordinate system rotated 45° from the x-y coordinate system of the plane. The stage, coupled to the mover, moves with corresponding motions of the mover relative to the stator. The position-measurement device includes a first group of four magnetic-field sensors that are movable with the stage. The sensors are situated at integer multiples of ?/2 from each other in u- and v-directions of the u-v coordinate system. The sensors produce respective data regarding a respective component of the magnetic field at, and hence the position of, the respective sensor within the period of the magnetic field.

Abstract: An energy converter includes a magnetism generation mechanism unit that generates a magnetic field when connected to an AC electrical power source, and a rotating mechanism unit having a single turn coil array member in which a plurality of single turn coils is disposed at a predetermined interval and a soft magnetic metal plate disposed on a side of the single turn coil array member opposite to the magnetism generation mechanism unit. The rotating mechanism unit is structured such that the single turn coil array member faces the magnetism generation mechanism unit across a predetermined magnetic gap and rotary driven by the magnetic field. Here, a drive signal period of the electrical power source is a period that maximizes an eddy current generated in the soft magnetic metal plate.

Abstract: A motor includes a sensor magnet having a non-circular contour and a magnet cover fixed to an end portion of a shaft to cover the end portion of the shaft. The magnet cover includes a support portion positioned outside the end surface of the end portion of the shaft. In the support portion, a magnet hole having a non-circular cross section as the sensor magnet and extending in the direction of the rotation axis is provided. The sensor magnet is inserted into the magnet hole and fixed to the magnet hole.

Abstract: A hybrid controller for a mechanical system includes an actuator configured to position a load. A vibration attenuation controller produces a vibration attenuation control signal in response to an input signal for the mechanical system. A tracking controller configured produces a tracking control signal in response to the input signal. In response to an output signal from the mechanical system, either the vibration attenuation control signal or the tracking control signal is switched as a control signal for the mechanical system to reduce both vibration in the mechanical system and improve tracking the load.

Abstract: An electronic control unit (100) detects the position of an output shaft (221) by counting a position count value based on pulse signals generated from position sensors (S4, S5) in accordance with rotation of a motor (210). The electronic control unit (100) determines that the motor (210) is in a predetermined rotational phase, based on the pulse signals generated from the position sensors (S4, S5). The electronic control unit (100) determines the number of revolutions that have been made by the motor (210) when the determination is made, based on the magnitude of current applied to the motor (210) when the determination is made, and updates the position count value based on a reference count value stored in association with the predetermined rotational phase.

Abstract: A gear control system includes a pulse modulating circuit, a motor, and a central processing unit operatively coupled to the pulse modulating circuit and configured to control rotation of the motor from an original gear position to a desired gear position via the pulse modulating circuit. A motor position detecting device is operatively coupled to the central processing unit and detects the motor rotation position and transmits the motor position information corresponding to the motor rotation position to the central processing unit. The central processing unit determines whether the motor has reached the desired gear position based on the motor position information, and actuates the pulse modulating circuit to transmit pulses to actuate the motor to reach the desired gear position when the motor has not reached the desired gear position.

Abstract: A system for controlling a motorized track light system constrained to travel along a track has a control unit coupled to a motor that causes the track light system to move along the track, a plurality of stop sensors strategically disposed along the track, a sensor activation device located on the track light system, the sensor activation device positioned to interface with the stop sensors, and a light sensor for detecting ambient light of a preset level. The system detects a preset level of ambient light, initiating power to the motor of the track light system, moving the lights along the track until the activation device interfaces with a first of the plurality of stop sensors, stopping movement of the track light system along the track for a preset period of time, and at the end of the preset time period, the electrical power is restored to the motor moving the track light assembly along the track to the next of the plurality of stop sensors.

Abstract: An electrical machine apparatus includes an electromagnetic coil, a rotor magnet, n (n is an integer not less than 2) magnetic sensors to detect an electric angle of the rotor magnet, and a position detection part to detect a position of the rotor magnet by using outputs of the magnetic sensors. Each of the magnetic sensors generates a sensor output signal having a curved line waveform and a period of electric angle 2? of the electrical machine apparatus. The respective n magnetic sensors are arranged to generate the sensor output signals with a phase difference other than an integer times ? in electric angle. The position detection part calculates a movement amount of the rotor magnet from a starting point as a position before movement by using the sensor output signals of the n magnetic sensors.

Abstract: Multi-rotation hobby servo motors are provided. In one embodiment, a hobby servo motor comprises a rotatable output shaft, a feedback mechanism, and a control circuit. The feedback mechanism generates a feedback signal that is indicative of rotation of the rotatable output shaft, and the control circuit utilizes the feedback signal to generate a control signal for the rotatable output shaft. The feedback mechanism is optionally an encoder such as, but not limited to, a magnetic encoder, an optical encoder, a rotary encoder, or a linear encoder.

Abstract: The rotation period of a motor is subdivided by edge interval times and a rate of change between a currently calculated edge interval time and an edge interval time calculated one rotation of the motor previously is calculated at the detection of each edge. Then the rotation period of the motor is calculated by multiplying a set reference period by the calculated rate of change.

Abstract: An exemplary stage apparatus has a motor, stage, and position-measuring device. The motor has a planar stator and moving-coil mover (planar motor). The stator is a checkerboard magnet array extending in an x-y plane and producing a magnetic field having a field period of 2? in a u-v coordinate system rotated 45° from the x-y coordinate system of the plane. The stage, coupled to the mover, moves with corresponding motions of the mover relative to the stator. The position-measurement device includes a first group of four magnetic-field sensors that are movable with the stage. The sensors are situated at integer multiples of ?/2 from each other in u- and v-directions of the u-v coordinate system. The sensors produce respective data regarding a respective component of the magnetic field at, and hence the position of, the respective sensor within the period of the magnetic field.

Abstract: Systems and methods for a linear motor having an integrated position sensing of the anchor of the motor are disclosed. An integrated position sensing of the anchor is achieved by sensing the inductance of one or more coils driving the anchor. The anchor comprises at least one permanent magnet. The inductance is dependent on a current position of the anchor. The anchor is driven by PWM pulses. A control unit controls the duration of driving the anchor and the duration of sensing the inductance. In normal operation during about 80% of a motor control period the anchor is driven and during a remaining time the inductance is sensed. In a preferred embodiment of the invention the linear motors invented are used in a camera module driving a lens barrel and a shutter.

Abstract: A linear feedback positioning module is provided with a coupling and a drive at one side of a platform having a lead screw, a movable assembly combined on the lead screw and a feedback assembly. The feedback assembly includes a magnetic scale cooperating with a read head. The magnetic scale is combined on the platform and located along the lead screw to cooperate with the lead screw. The linear feedback positioning module is further used with a backend control assembly. By such arrangements, the feedback assembly can correct error at any moment to improve the process and product accuracy and increase the production efficiency and product competitiveness.

Abstract: A movable member is moved in a preset direction in a linear motor. A characteristic-change position-detecting unit detects a position where the magnetic characteristic of the magnets has abruptly changed. The position detected is used as an origin-setting reference position. A reference position for the absolute position of the magnetic linear encoder is set based on the reference position.

Abstract: A motor rotational position detecting method detects the magnetic pole position of each phase of a three-phase AC servomotor, generates a three-phase square wave signal having a phase difference of 120 degrees, allocates data on the rotational position of a motor shaft to the edge of each square wave signal, calculates the rotational speed of the motor on the basis of the elapsed time from the previous edge detection point to this time edge detection point, and estimates the rotational position of the motor shaft at a certain period and outputs it on the basis of the rotational speed of the motor and the rotational position allocated to this time edge in the rotational section from this time edge detection point to the next edge detection point. As a result, a detection mechanism can be constructed with a small installation space and at low cost and the output of a high-resolution encoder can be obtained in a pseudo manner.

Abstract: A gear control system includes a pulse modulating circuit, a motor, and a central processing unit operatively coupled to the pulse modulating circuit and configured to control rotation of the motor from an original gear position to a desired gear position via the pulse modulating circuit. A motor position detecting device is operatively coupled to the central processing unit and detects the motor rotation position and transmits the motor position information corresponding to the motor rotation position to the central processing unit. The central processing unit determines whether the motor has reached the desired gear position based on the motor position information, and actuates the pulse modulating circuit to transmit pulses to actuate the motor to reach the desired gear position when the motor has not reached the desired gear position.

Abstract: A stator position measuring method and device relating to a motor driving device including a motor case, a rotor, and a stator disposed on an outer periphery of the rotor concentrically with the rotor, includes measuring a position of the stator relative to an axial center of the rotor, wherein the position of the stator is determined in a rotor not-inserted state, in which the stator is housed inside the motor case and the rotor is not inserted in the stator, by measuring a position of a radial surface of a stator core, which includes a magnetic body or a conductor forming the stator, relative to the axial center of the rotor using a non-contact displacement sensor that is selectively sensitive to the magnetic body or the conductor.

Abstract: An aperture closure member control arrangement includes a disc which rotates as the aperture closure member moves. The disc has a ring of teeth. A sensor, such as a Hall effect sensor and permanent magnet, detect the passage of teeth as a cyclic waveform of amplitude and frequency determined by the spacing of the teeth, and the speed of rotation of the disc. An irregularity in the form of a missing tooth creates an irregularity in the output of the sensor, in the form of a pulse of greater amplitude and lower frequency. Accordingly, pulses from the irregularity can be discriminated and counted to provide a coarse indication of position, or pulses from the teeth can be counted, to provide a fine indication.

Abstract: Position detection of a medical device is prevented from being impossible even when the frequency characteristic of a magnetic induction coil is varied in accordance with the state of an external magnetic field for guiding the medical device.

Abstract: A legged mobile robot gives up a normal walking motion and starts a tumbling motion when an excessively high external force or external moment is applied thereto and a behavior plan of a foot part thereof is disabled. At this time, the variation amount ?S/?t of the area S of a support polygon of the body per time t is minimized and the support polygon when the body drops onto a floor is maximized to distribute an impact which acts upon the body from the floor when the body drops onto the floor to the whole body to suppress the damage to the body to the minimum. Further, the legged mobile robot autonomously restores a standing up posture from an on-floor posture thereof such as a supine posture or a prone posture.

Abstract: An electric drive apparatus has an electric motor having a rotor and a stator; and a magnetic pole position detecting portion having a sensor rotor attached to the rotor, and a sensor stator that is adjacent to the stator, and that is fixed to a case, and that extends over a partial region of the sensor rotor extending in a circumferential direction. Because the sensor rotor of the magnetic pole position detecting portion is attached to the rotor and the sensor stator is adjacent to the stator and is fixed to the case, it is no longer necessary to use an all-round embracing type magnetic pole position detecting portion that embraces the entire shaft of an electric machine.

Abstract: A method and an apparatus for estimating the position of a moving part of a linear actuator are provided. The method comprises the following steps. Move the moving part towards a target position. Receive magnetic signals generated by the magneto-resistive sensor of the linear actuator, which include a sine signal and a cosine signal. Then, generate a first square wave, a second square wave, and a regional square wave based on the sine signal and the cosine signal. Generate a saw-tooth wave based on the sine signal, the cosine signal, the second square wave, and the regional square wave. Next, calculate the number of regions which the moving part is across from the origin point based on the first square wave, the second square wave, and the regional square wave. Finally, estimate the current position of the moving part based on the saw-tooth wave and the number of regions.

Abstract: An apparatus and a method for correcting a position of a mobile robot includes a position notifying unit, installed at a predetermined position, that generates and transmits a signal indicative of the predetermined position. The mobile robot includes a position signal detector, installed at a predetermined position of the mobile robot, that detects a signal; and a control unit, installed at a predetermined position of the mobile robot, that corrects a position of the mobile robot on the basis of pre-stored position information corresponding to the detected position signal, so that a position error that is generated when the mobile robot moves is corrected.

Abstract: A stationary position detection circuit and a motor drive circuit capable of more properly detecting the rotor position are disclosed. The stationary position detection circuit supplies an alternating current to each phase load of the motor. The time during which the current flows in a first direction and the time during which the current flows in a second direction opposite to the first direction are converted into electrical signals and amplified. In accordance with the value of the electrical signals, the position of the motor rotor in stationary mode is determined. The use of the alternating current, unlike the kickback voltage, makes it possible to improve the detection accuracy by amplifying the electrical signals with an increased number of alternations. An increased number of alternations can amplify the electrical signals without increasing the value of the alternating current, and therefore, unlike in the case of the kickback voltage, the alternating current of a large value is not required.

Abstract: The actuator and the method for operating the actuator comprise a drive unit and a drive mechanism with mechanical components that can be moved against each other as well as an electronic control unit. One of at least two components that can be moved against each other during operation acts as a switching transducer and initiates a switching operation in the event of relative movement in respect of a switching element, for example a Reed switch, caused by the action of an external force. This switching operation is used in the course of the control method to switch the control unit from a first operating mode to a further operating mode.

Abstract: The present invention provides a motor control system and method thereof. The motor control system comprises a motor controller and a compensation device. The motor controller is used for generating a motor control output according to a reference signal and a first signal. The compensation device is used for generating a compensated motor control output according to the motor control output and a second signal. Moreover, the compensation device utilizes the compensated motor control output to reduce the steady-state phase error between the first signal and the reference signal.

Abstract: A control apparatus for a machine that can be operated at high precision in a stable control state is provided by driving a movable body with control parameters suited to the mechanical state. A control parameter calculation circuit is provided to obtain control parameters for a drive apparatus control circuit for driving actuators in accordance with the conditions of actuator rotational velocity, the orientation of the movable body, and the position of the movable body, and a control parameter K for the drive apparatus control circuit is varied.

Abstract: A deviation angle detector enlarges the application range by enlarging the detectable deviation angle range. The deviation angle detector has two resolvers, which have rotors, stators, and single excitation windings and multiple output windings that are coiled around the stators. The difference in rotation angles of the resolvers is detected as a deviation angle ?? by calculating the output signal that corresponds to the rotation angles of the resolvers digitally or in analog. The corresponding output windings of the resolvers are connected in series and the output signals are extracted from the serially connected output windings and calculated digitally or in analog.

Abstract: The invention relates to a circuit arrangement and a method for operating an electric motor in a direct voltage source, in particular for operating a permanent-magnet-excited DC motor in the direct voltage network of a motor vehicle, having a rotary position transducer (32) for detecting the rotary position of the rotor (20), and having an electronic commutation controller (32) for switching over the current in the armature winding of the stator (12) as a function of the position of the rotor (20). It is proposed that the rotary position transducer (32) is positioned relative to the stator (12) for an early commutation, and that the actual commutation time can be set by means of a delay correction, ascertained by measurement separately for each motor (10), in the electronic commutation controller (30).

Abstract: A flux compensated rotational position detector includes a rotating element having a plurality of magnetic poles extending over its entire periphery, and a fixed element having a plurality of protruding fixed-element magnetic poles with fixed-element magnetic pole teeth opposing the rotating element, and first and second compensating poles disposed on either side of the fixed-element magnetic poles, the first and second compensating poles having respective first and second magnetic pole teeth opposing the rotating element, wherein the fixed element does not form a closed magnetic path around the entire periphery of the rotating element, magnetizing windings are provided on all of the first and second compensating poles and the fixed-element magnetic poles, and sine output and cosine output windings are provided on each of the fixed element magnetic poles. Methods for operating the detector are also described.

Abstract: The invention provides a device to generate an rpm-dependent signal, or a tachogenerator, having a plurality of magnet elements with alternating polarity which are arranged and distributed around the circumference of the rotor shaft. The magnet elements preferably take the form of a magnetic ring which has alternatively polarized sections and is held on a support attached to the rotor shaft. The tachogenerator of the present invention has at least one coil parallel to the axis which is arranged on a second supporting device at an axial distance to the magnet elements. The magnets and coils are arranged spatially relative to each other and can be rotated in relation to each other with the rotation of the rotor shaft in order to induce an rpm-dependent signal in the coils. In accordance with the invention, a signal displacement device is provided which superimposes a DC voltage on the signals induced in the coils in order to generate a voltage-displaced signal.

Abstract: A strategy to control and diagnose the operation of an electric motor using a sensorless control system augmented by feedback from a position and speed sensor is disclosed. The strategy can improve the robustness of operation and diagnose potential faults in electric motors. The present invention includes a method for diagnosing operation of an electric motor and a method and system for controlling an electric motor. In the diagnostic method, a sensorless system and a sensor based system are checked against each other to determine if either of the systems is faulted. In the control method, the sensor based control system is used when the motor speed is below a predetermined threshold and the sensorless system is used when the motor speed is above the predetermined threshold. The position sensor can be a low resolution position sensor, an engine crankshaft sensor, an engine camshaft sensor, or a transmission sensor.