Abstract: O2O (Offline to Online) Management System is a computer-implemented service which manages the operation and interaction among the brick-and-mortar stores, merchants, warehouse and product providers. It also manages the purchase transactions by the customers at online marketplace and the brick-and-mortar stores. Unlike the online shopping services which provide only storefront Web access, the O2O Management System integrates the transaction and operation of online marketplace, brick-and-mortar retail stores, merchants, warehouses and product providers with a network of computer systems, such as internet. The transaction of O2O Management System occurs in the combination of physical retail facility (retail store) and internet.

Abstract: A system and method for facilitating predictive maintenance of an equipment is disclosed. The system may include a data capturer, a plurality of edge computing nodes and a cloud computing device. Each edge computing node may include a first processor. The cloud computing device may include a second processor. The first processor may receive the raw input data from the data capturer and may process the raw input data to obtain a representative data. The representative data may include an insight pertaining to a deviation in the at least one variable and a corresponding remedial action to be taken to correct the deviation. The deviation may be related to a deterioration in the condition of the equipment. The respective edge computing node may facilitate a regulation of the deviation by performing an automated actuation based on the corresponding remedial action.

Abstract: Systems and methods use cameras to provide autonomous navigation features. In one implementation, a method for navigating a user vehicle may include acquiring, using at least one image capture device, a plurality of images of an area in a vicinity of the user vehicle; determining from the plurality of images a first lane constraint on a first side of the user vehicle and a second lane constraint on a second side of the user vehicle opposite to the first side of the user vehicle; enabling the user vehicle to pass a target vehicle if the target vehicle is determined to be in a lane different from the lane in which the user vehicle is traveling; and causing the user vehicle to abort the pass before completion of the pass, if the target vehicle is determined to be entering the lane in which the user vehicle is traveling.

Abstract: A system to control slip-stick stages that includes a slip-stick stage including an actuator and a processor coupled to the actuator to obtain a frequency, a number of measurement samples, and a voltage; determine a time period based on the number of measurement samples and the frequency; sample a displacement of the actuator during the time period. The system functions to calculate an error value based on the displacement and a reference position; determine a step value based on the error value and a modulation protocol. The modulation protocol includes a proportional modulation protocol or a proportional-integral modulation protocol to generate a control signal based on the step value, the frequency and the voltage based on an integral of a function of voltage and a Heaviside function according to a direction specified by a sign of the step value; and transmit the control signal to the actuator.

Abstract: A position control method for a servo, includes: receiving, from a control terminal, a motion control command that comprises a motion planning parameter about position of an output shaft of the servo; acquiring speed information or time information indicated by the motion planning parameter, and determining a constant parameter control duration according to the speed information or time information; determining a control parameter corresponding to a constant parameter control stage according to the constant parameter control duration and a preset constant parameter; performing a transient adjustment to the servo when the constant parameter control stage ends, and changing the control parameter to an adaptive operation parameter when the transient adjustment ends; and controlling a rotation angle of the output shaft of the servo to perform a position control of the servo, based on duration values and control parameters corresponding to each of a plurality of control stages.

Abstract: An electric machine (e.g., motor or generator) for an electric drive system of an electric vehicle is adapted to be coupled to wheels of the vehicle for conversion between stored electrical energy and rotation of the wheels. A resolver is coupled to the electric machine having a rotor rotating with the electric machine, the resolver responding to an excitation signal to produce a position signal. A controller is coupled to the resolver to receive the position signal and coupled to the electric machine to control the conversion. The controller generates the excitation signal at a variable frequency selected as a function of an operating point of the electric machine to avoid harmonic noise peaks propagating at the electric machine. Consequently, the position signal is relatively less affected by electromagnetic noise.

Abstract: Monolithic attenuator, limiter, and linearizer circuitry to be integrated with other circuitry on a chip are provided. According to one aspect, a monolithic attenuator and limiter circuit comprises an input terminal, an output terminal, a first resistor having a first terminal coupled to the input terminal and a second terminal coupled to the output terminal, and a second resistor having a first terminal coupled to the first or second terminal of the first resistor and a second terminal coupled to ground. At least the first resistor is a non-linear resistor whose resistance changes as a function of the voltage across the resistor. The monolithic attenuator and limiter circuit may be part of a “Pi” or “Tee” topology. According to another aspect, a non-linear shunt resistor coupled to the input of an amplifier circuit can operate to linearize the gain of the amplifier circuit over a range of input levels.

Abstract: A fuel cell system includes a compressor provided in a cathode gas supply passage configured to feed the cathode gas under pressure to the fuel cell, a bypass passage configured to discharge the cathode gas fed under pressure by the compressor to a cathode gas discharge passage while bypassing the fuel cell, a bypass valve provided in the bypass passage and configured to adjust a flow rate of the cathode gas flowing in the bypass passage, a system stopping unit configured to stop the fuel cell system by performing a predetermined stop sequence process when a request to stop the fuel cell system is made, and a stop-time bypass valve control unit configured to control a valve body of the bypass valve to a predetermined initialization position in parallel with the sequence process during the stop sequence process.

Abstract: An apparatus and a method for controlling a motor are provided. The apparatus for controlling a motor includes a temperature sensor that is configured to detect a temperature of an inverter, and a variable amplifier that is configured to variably set an amplification gain that corresponds to the detected temperature of the inverter and amplify and output a resolver signal output from a resolver based on the variably set amplification gain, based on an excitation signal. A controller is then configured to estimate a position of a motor rotor based on the amplified resolver signal to calculate a flux angle and an excitation signal generator is configured to generate the excitation signal that corresponds to the calculated flux angle and output the generated excitation signal to the resolver.

Abstract: A data storage device is disclosed comprising a head actuated over a disk surface comprising tracks defined by servo sectors, wherein each servo sector comprises at least one servo burst comprising a periodic pattern. The servo burst of one of the servo sectors is read to generate a read signal, and M intermediate integration points yNi are computed according to: y N i = ? k = 0 N i ? r ? ( k ? ? T s ) · sin ? ( ? ? ? k ? ? T s ) ; i = 0 , 1 , … ? , M - 1 where r(kTs) represents a sample point of the read signal, Ts represents a sample interval between the sample points, and ? represents a frequency of the periodic pattern in the servo burst.

Abstract: A motor control device has a current value sampling unit configured to sample a current value of a motor, a PWM signal generation unit configured to generate a PWM signal to drive the motor, based on the sampled current value of the motor, and a power supply stop unit configured to stop supply of power from a control power supply to a peripheral depending on power stored in a DC link part and power to which the control power source can supply when an alternating-current power source fails.

Abstract: A PWM signal generation unit generates a PWM signal to drive a motor, based on a current value of the motor sampled by a current value sampling unit, a position or speed of the motor sampled by a motor sampling unit, and a position or speed of a driven object sampled by a driven object sampling unit. An operation stop unit stops the operation of any one of the motor sampling unit and the driven object sampling unit depending on the power stored in the DC link part and power to which the control power source can supply when the alternating-current power source fails.

Abstract: A resolver signal converter and a resolver signal conversion method amplify and perform analogue-digital conversion on a sine wave output from a resolver; thereafter, among frequency components of the sine wave output, pass and thereby extract a predetermined bandwidth of which the center frequency is the frequency of an excitation signal, by means of a band-pass filter; sample the sine wave output while synchronizing the sine wave output with a reference signal which is based on the excitation signal; and generate a detection angle signal sine value from the sampled signal. Similarly, a detection angle signal cosine value is generated from a cosine wave output from the resolver. A detection angle is calculated based on the detection angle signal sine value and the detection angle signal cosine value.

Abstract: Disclosed herein is a motor control apparatus and a method thereof. The operation efficiency of a compressor may be maintained by using a sensorless algorithm, sampling a current applied to a motor more than twice within a period of the triangular carrier wave for performing pulse width modulation to calculate a reference voltage, driving the motor according to the calculated reference voltage to improve control resolution, and performing a high-speed operation while reducing a volume of the compressor, without adding a separate hardware when controlling the operation of the motor provided in the compressor at a high speed.

Abstract: A distributed motor drive system includes a power management module and multiple inverter modules integrated with the motors and located on a machine or process remote from the power management module. The power management module distributes DC voltage and command signals to each of the inverters, where the DC voltage is distributed between modules via a DC link cable. The integrated inverters execute switching routines to convert the DC voltage to an AC voltage suitable for controlling the motor. Each of the power management module and the inverters includes a portion of the DC bus. The current on the DC link cable is monitored and general bus utilization as well as overload conditions are reported.

Abstract: A motor controller receiving as input an encoder signal changing in response to a driving position of a motor, outputting a motor driving command in response to the encoder signal to control at least one of the driving position or a driving velocity of the motor, includes an interrupt processing section to execute interrupt operations every prescribed interrupt cycle, a low-frequency processing section to selectively execute a subset of the interrupt operations every prescribed number of the interrupt cycles, and a high-frequency processing section to execute another subset of the interrupt operations every prescribed interrupt cycle, wherein the high-frequency processing section executes at least an operation to detect the driving position indicated by the encoder signal, wherein the low-frequency processing section executes at least an operation to generate the motor driving command.

Abstract: A linear drive based on linear motors, for panels, in particular sliding doors, movable along a respective travel path. A linear drive for at least one panel, in particular a sliding door leaf, movable along a travel path, has at least one linear motor for this at least one panel. The linear motor is provided with a stator member and a carriage. Furthermore, the linear drive has a control circuit. The control circuit is adapted to stop the linear motor in the event of failure of power supply to the linear motor, by switching-off the linear motor and operating it as a generator. Thereupon, in terms of its displaceability, this movable panel is enabled by the control circuit. In addition, the linear drive has a switch for switching-off the energy supply to the at least one linear motor.

Abstract: A control method for a sensor-less, brushless, three-phase DC motor. A pulse-width modulation (PWM) duty cycle may be calculated. A voltage induced by rotation of a rotor may be sampled at a first expected zero crossing value to produce a first sampled voltage value. An average of a plurality of sampled voltage values, including voltage values sampled at a plurality of prior expected zero crossing values and the first sampled voltage value, may be calculated. The first sampled voltage value may be subtracted from the calculated average to produce a delta zero crossing error (ZCE). The current value of an integral term corresponding to a rotational period may be updated according to the sign of the ZCE. The integral term may be updated periodically and multiple times during each rotational period. The ZCE may be subtracted from the integral term, and the resulting value may be used to generate one or more time values.

Abstract: The effect of chattering on the measurement of the pulse period is reduced. The pulse period representing the rise interval of target pulses appearing in a pulse signal PI is measured. The pulse signal PI is sampled in synchronization with a measurement clock CLK. Measurement of a designated inhibition period is started in synchronization with the fall of the signal PI. Measurement of the current pulse period is completed and measurement of a new pulse period is started if the inhibition period has elapsed at the rise of the signal PI. Counting of the current pulse period is continued if the inhibition period has not elapsed.

Abstract: A robust method for detecting a relative position of a feedback device, such as an encoder or resolver, coupled to a shaft, such as a motor shaft, is provided. To detect the relative position, electrical commands are issued in an open loop mode to spin the motor shaft an amount greater than the apparent rotational angle between two consecutive markers of the position feedback device, such that the net mechanical rotation is equal to or greater than the total rotational angle between two consecutive markers.

Abstract: The invention provides a driving circuit for a voice coil motor. In one embodiment, the driving circuit includes a logic circuit, a digital-to-analog converter, and an output circuit. The logic circuit generates a series of samples of a digital output signal according to a digital input signal, wherein the samples of the digital output signal sequentially alter from a first input value of the digital input value to a second input value of the digital input signal according to an alteration pattern determined by a mode selection signal. The digital-to-analog converter converts the digital output signal to an analog output signal. The output circuit generates a driving current signal according to the analog output signal for driving the voice coil motor.

Abstract: A method of closed-loop controlling determines a first feedback variable by sampling a control variable and a second feedback variable by averaging the control variable, compares the first and second feedback variables with a command variable, and sets the control variable on the basis of the comparing result so that the control variable follows a command variable.

Abstract: In a motor control apparatus, apparatus all switching devices of all phases of an inverter are kept fixed at OFF in accordance with a value of an all-OFF control pulse signal Poff outputted by a pulse generator. The pulse generator generates at least twice a pulse causing an induced voltage detection signal Pdet to change to an H level. A terminal voltage of a motor is inputted in accordance with the value of the induced voltage detection signal Pdet. Data of the sampling round in which amplitude of the induced voltage signal is great and the signal is not in saturation is selected from the data so inputted and a rotor position is estimated.

Abstract: The non-linear elastic deformation component included in the angular transmission error of an actuator provided with a wave gear drive is a component of the angular transmission error occurring due to elastic deformation of a flexible externally-toothed gear when the direction of rotation of the motor shaft changes. This component can be analyzed by driving the motor in a sine-wave shape. A model of the non-linear elastic deformation component (non-linear model) obtained from the analysis results is used to store data or a function for compensating for this component in a motor-control device. Compensation for the non-linear elastic deformation component (?Hys) is added to a motor-shaft angle command (?*M) as a compensation input (N?*TE) for feed-forward compensation. As a result, the non-linear elastic deformation component (?Hys) can be effectively reduced, and the positioning precision of the actuator can be improved.

Abstract: A method is specified for operating a rotating electrical machine, in which the rotating electrical machine is connected in terms of phase to a converter circuit, having a DC voltage circuit, for connecting at least two voltage levels, and the phases of the converter circuit are connected to the DC voltage circuit in accordance with a selected switching state combination of switching states for power semiconductor switches in the converter circuit. In order for operation of the rotating electrical machine to be possible in an event, over a number L of sampling times various values are determined, and a switching state combination is set as the selected switching state combination with which a sum of determined values is at its smallest.

Abstract: A sensorless controlling apparatus for controlling a brushless motor includes a speed calculator for calculating speed of a rotor ?, an angle calculator for calculating rotor angle ? at a predetermined time interval, and an angle controller for calculating correction angle ?? based on the current value of a d-axis current (d-axis current value id), thereby controlling the rotor angle ?. The angle calculator uses the correction angle ?? calculated by the angle controller, the speed ? calculated by the speed calculator, a predetermined time, and the rotor angle ? calculated by the angle calculator at a predetermined time to calculate the rotor angle at the predetermined time interval. Thus, the rotor angle ? calculated by the angle calculator is converged on the true angle of the rotor.

Abstract: A system for generating a motion profile in real time includes a processor. The processor breaks a move into a first phase and a second phase. The first phase includes commanding the move toward a constant velocity segment, and the second phase includes monitoring the first phase to determine when during a move in progress it is necessary to implement a jerk value required to successfully reach end conditions. The processor also transmits command signals based upon the motion profile and calculates the point at which the second phase must take control of the move in progress to reach a target position. The system further includes at least one input/output module that receives command signals. A method for generating a motion profile in real time is also presented.

Abstract: A method for reducing audible motor noise in a motor drive, wherein the motor drive includes a motor controller driving a PWM space vector modulator providing gating pulses to an inverter providing phase currents to the phase windings of the motor, and wherein phase currents of the motor are determined by taking samples of the DC link current in a DC link powering the inverter. The method comprises determining the speed of the motor and comparing the speed to a preset threshold, the preset threshold defining a speed at which audible noise is generated by the motor due to a minimum pulse constraint being imposed on the motor phase currents in order to reliably sample the DC link current to measure the phase current. If the speed is below the threshold, the DC link current in the DC link is sampled using a reduced number of current samples for a PWM cycle of the PWM space vector modulator to reduce audible motor noise.

Abstract: A motor driving device includes an amplifying unit, a noise removing unit, an analog-to-digital converter, a calculating unit, and a motor driving unit. The amplifying unit amplifies an analog frequency signal corresponding to a rotation speed of a direct-current brushless motor. The noise removing unit removes noise from the analog frequency signal after amplification. The analog-to-digital converter converts the analog frequency signal from which noise is removed to a digital frequency signal. The calculating unit calculates a current control amount with respect to each phase of the direct-current brushless motor based on the digital frequency signal. The motor driving unit drives the direct-current brushless motor at a specified speed based on the current control amount.

Abstract: A method of closed-loop controlling determines a first feedback variable by sampling a control variable and a second feedback variable by averaging the control variable, compares the first and second feedback variables with a command variable, and sets the control variable on the basis of the comparing result so that the control variable follows a command variable.

Abstract: The invention relates to a method and an arrangement for a digital servo system with moving average filter (Amovavf 1, Amovavf 2),which is used as an input filter for a digital signal processor of the servo system to shorten processing delay, which improves the stability of the control loop and/or allow a fast servo signal processing, which improve the overall servo signal control performance. Said input filter provides average values of samples provided from an analog digital converter (ADC) at a frequency corresponding to a sample frequency (fADC) of the analog digital converter (ADC) and has an adjustable filter length (n), which is determined according to a quality of detector signals indicating a deviation from a target of servo means of the servo system. The invention is e.g. applicable for a fast digital servo system in an optical disc drive.

Abstract: Self-sensing feedback functionality for electromechanical actuators/motors is provided for use in operation and/or as a redundant safety mechanism to attain safety certification without adding extra bulk or wiring to the motor. An actuator can be manufactured having one or more saliencies that cause a spatial variance of inductance. A high frequency signal can be injected into the actuator and sampled to determine a current, voltage, or other electrical parameter. The parameter can be evaluated against the known saliencies of the actuator to determine a position of the actuator and/or an associated rotor. Additionally, the position can be evaluated as a function of time to determine a velocity. This can provide an alternative method for operating the electromechanical actuator according to the position/velocity provided. Additionally, this can provide a redundant feedback channel for safety certification without requiring additional actuator parts.

Abstract: A motor control processor is provided for motor phase current sampling of multiple variable frequency controlled electric motors. The motor control processor comprises an analog-to-digital (A/D) converter and a controller. The A/D converter has multiple analog inputs and generates a digital output signal in response to the multiple analog inputs. The controller is coupled to the A/D converter and determines a maximum desired switching frequency for a first one of the multiple variable frequency controlled electric motors. The controller further selects a base period in response to the maximum desired switching frequency and defines a phase shift time delay as a fraction of the base period so that the controller may control the multiple analog inputs of the A/D converter to sample motor phase currents of each of the multiple variable frequency controlled electric motors at sample times determined by the controller in response to the base period and the phase shift time delay.

Abstract: The present invention provides a diagnostics methodology and embedded electronic system that allows optimized low-frequency data sampling for EMA motoring subsystems in an operating vehicle. Each of the EMA motoring subsystems includes: an EMA; at least one motor for driving the EMA; and power controls for operating the motor, wherein the power controls includes a DSP controller for sampling and processing data at low-frequency sampling rates. The diagnostic methodology includes a method that has the steps of: determining an operational mode of the EMA motoring subsystem; selecting a sampling rate optimized for the determined operational mode; acquiring and processing data at the selected sampling rate; and analyzing the processed data to identify and classify a fault of the EMA motoring subsystem.

Abstract: Methods and apparatus for controlling a polyphase motor in implantable medical device applications are provided. In one embodiment, the polyphase motor is a brushless DC motor. The back emf of a selected phase of the motor is sampled while a drive voltage or the selected phase is substantially zero. Various embodiments utilize sinusoidal or trapezoidal drive voltages. The sampled back emf provides an error signal indicative of the positional error of the rotor. In one embodiment, the sampled back emf is normalized with respect to a commanded angular velocity of the rotor to provide an error signal proportional only to the positional error of the motor rotor. The error signal is provided as feedback to control a frequency of the drive voltage. A speed control generates a speed control signal corresponding to a difference between a commanded angular velocity and an angular velocity inferred from the frequency of the drive voltage.

Abstract: A DC motor phase estimation algorithm that estimates a speed-related harmonic frequency of a DC motor current under dynamic load conditions having known geometry parameters. The algorithm estimates the phase and magnitude of a complex coefficient in a complex single frequency adaptive filter that receives a primary signal from the motor current and estimates a reference signal using an incident frequency by adapting the complex coefficient to match the magnitude and phase of the speed-related harmonic component of the primary signal. The rate of change of the phase of the complex coefficient is determined by a phase-lock loop coupled to the adaptive filter to adapt a dynamic incident frequency corresponding to a single frequency component of interest in the primary signal. The incident frequency is extracted, and the motor speed is estimated using the extracted incident frequency and the known motor geometry parameters.

Abstract: This invention provides methods for electric vehicle motor control and rotor position detection and fault-tolerant processing. The rotor position signal sampled by the system is compared with the previous rotor position ?0. When there is a sudden change, the current position signal acquired is discarded. Instead, a fault-tolerant processing strategy for use during an error condition is employed where the previous sampled rotor position ?0 is used as a base to determine the corrected current rotor position angle ?1?. Then the correcting value is used to control the electric motor.

Abstract: Apparatus for reconstructing the phase currents of a multiphase load driven by a multiphase inverter fed by a DC link and controlled by a PWM controller, the apparatus including a sensor in the DC link, first and second sampling arrangements for sampling the current in the DC link by obtaining an output from said sensor, the first sampling arrangement obtaining a first sample of the current in the DC link during a first time period corresponding to a first switching pattern of said multiphase inverter and storing said first sample; the second sampling arrangement obtaining a second sample of the current in the DC link during a second time period after said first time period and corresponding to a second switching pattern of said multiphase inverter and storing said second sample; an A/D converter for converting said first sample to a digital signal during a time period after said first time period and for converting said second sample to a digital signal during a following third time period.

Abstract: Method of controlling a movable member driven by an electric motor by monitoring current circulating through the electric current and ripples therein. The method including detecting current peaks and count the number of current peaks falling within sampling windows such that the number of current peaks falling within the sampling windows are used to determine an angular position of the electric motor for use in facilitating the control thereof.

Abstract: A method and apparatus provide a state observer control system 600 for a motor 106 that uses an extended Kalman filter 330 to predict initial rotor position and afterwards accurately predict rotor position and/or speed under variable types of loading conditions. A control system model 300 is generated that allows variable setting of an initial rotor position to generate estimated rotor position and speed as outputs. The control system model 300 includes an EKF (extended Kalman filter) estimator 330, speed controller 322, a current controller 324, and a variable load component 310. During operation, EKF estimator 330 estimates rotor speed 327 and position 333 based on reference voltages 402, 404 and currents 1325 generated by speed and current controllers 322, 324 and input from frame transformers 326, 328.

Abstract: The present invention provides a diagnostics methodology and embedded electronic system that allows optimized low-frequency data sampling for EMA motoring subsystems in an operating vehicle. Each of the EMA motoring subsystems includes: an EMA; at least one motor for driving the EMA; and power controls for operating the motor, wherein the power controls includes a DSP controller for sampling and processing data at low-frequency sampling rates. The diagnostic methodology includes a method that has the steps of: determining an operational mode of the EMA motoring subsystem; selecting a sampling rate optimized for the determined operational mode; acquiring and processing data at the selected sampling rate; and analyzing the processed data to identify and classify a fault of the EMA motoring subsystem.

Abstract: An adjustment system is disclosed for adjusting a proportional, integral, derivative controller in a limited rotation motor system. The adjustment system includes a first transform unit, a second transform unit, a model identification unit, and a PID adjustment unit. The first transform unit is for receiving a first digital signal that is representative of a motor control signal, and is for providing a first frequency domain sequence that is representative of a frequency domain representation of the motor control signal. The second transform unit is for receiving a second digital signal that is representative of a position detection signal, and is for providing a second frequency domain sequence that is representative of a frequency domain representation of the position detection signal. The model identification unit is for identifying a representation of a ratio of the first and second frequency domain sequences.

Abstract: Disclosed are systems and methods for operating a barrier. In one embodiment, a door operator can be opened or closed by triggering either an internal device (e.g., wall button) or an external device. In one embodiment, if an obstacle is detected when the door is opening or closing, the door will either stop or swing in the reverse direction. In yet a further embodiment, the door operator is implemented using an alternating current (AC) synchronous motor.

Abstract: Methods and apparatus for controlling a polyphase motor in implantable medical device applications are provided. In one embodiment, the polyphase motor is a brushless DC motor. The back emf of a selected phase of the motor is sampled while a drive voltage of the selected phase is substantially zero. Various embodiments utilize sinusoidal or trapezoidal drive voltages. The sampled back emf provides an error signal indicative of the positional error of the rotor. In one embodiment, the sampled back emf is normalized with respect to a commanded angular velocity of the rotor to provide an error signal proportional only to the positional error of the motor rotor. The error signal is provided as feedback to control a frequency of the drive voltage. A speed control generates a speed control signal corresponding to a difference between a commanded angular velocity and an angular velocity inferred from the frequency of the drive voltage.

Abstract: A first drive voltage generating section corresponds to a first motor, and a second drive voltage generating section corresponds to a second motor. Each of the first drive voltage generating section and the second drive voltage generating section includes switching elements, an A/D converter, and an MPU. Each A/D converter samples an analog signal representing a load state of the corresponding motor. A clock circuit synchronizes the control periods of the drive voltage generating sections. Each MPU commands the corresponding A/D converter to sample the analog signal at timing where no switching is performed by any of the switching elements in the drive voltage generating sections. Therefore, the analog signals representing the load states of the motors are preferably sampled without being influenced by noise generated by switching.

Abstract: A controller controls an electric motor to provide assist power corresponding to steering operation for an electric power steering apparatus. The controller comprises a detecting device, a filtering device, a judging device and a determining device. The detecting device detects present voltage of a power source for the electric motor. The filtering device filters the present voltage based on a small time-constant when the voltage of the power source increases and based on a large time-constant when the voltage of the power source decreases. The judging device judges whether the filtered voltage is lower than a predetermined threshold. And, the determining device determines being abnormality of the power source when it is judged that the filtered voltage is lower than the threshold.

Abstract: The invention relates to a sensorless commutation of a direct-current motor. To allow an exact, easy to design, flexible, and highly integratable circuit arrangement for commuting motor devices, analogue phase detectors are replaced by digital devices, in particular Sigma-Delta-modulators, which oversample the induced voltages of coils of said motor.

Abstract: A system and method for controlling operation of a component include using at least two sensors arranged to sense an operating condition of the component. The system further includes a controller that controls the component in response to feedback signals output by one or more of the sensors. The controller also determines how the sensor feedback signals are to be used in controlling the component. To this end, the controller includes a model-based statistical filter for each one of the second sensors.

Abstract: A system and method for measuring fluid flow rate in a system where fluid is pumped, such as a gas monitoring instrument where gas is pumped from a space such as a room or enclosure through a conduit to a sensor. The flow of gas through a pump is determined by measuring motor back-e.m.f. which is proportional to motor speed. In a system where motor speed is regulated by pulse width modulation of the motor drive voltage, the back-e.m.f. is sampled during intervals between the drive pulses applied to the motor, and in a further aspect the sampling is done at selected, spaced-apart or infrequent intervals such as once for every ten or once for every hundred motor drive pulses. Advantageously, in an instrument that uses a microprocessor and analog-to-digital converter to measure gas-concentration, the same microprocessor and converter can provide the PWM control of the pump, in response to the back-e.m.f. generated by the pump motor between the drive pulses.

Abstract: A variable speed power tool may include a speed adjusting device and/or a maximum speed adjusting device for adjusting the operating speed, and a fixed operating speed switch. An operator adjustable speed adjusting device having a position maintaining mechanism also may be utilized. When manipulated by the operator, the fixed operating speed switch gives priority to the adjusted position of the speed adjusting device and adjusts the operating speed to a preset operating speed. In the alternative, a switching device and an internal integrated circuit may be utilized to adjust the operating speed to a target speed using feedback control. The switching device preferably selects a voltage corresponding to the target speed from either a voltage representative of the position of the speed adjusting device or a predetermined voltage representative of the present operating speed.