A sort buffer includes a phase sector determination circuit, a phase sector update circuit, and a phase sector completion circuit. The phase sector determination circuit is configured to determine a phase sector corresponding to a phase of a first sine and cosine sample pair received from an encoder or resolver. The phase sector update circuit is configured to determine whether a second sine and cosine sample pair corresponding to the phase sector is stored in a lookup table (LUT) and, in response to a determination that a second sine and cosine sample pair corresponding to the phase sector is not stored in the LUT, store the first sine and cosine sample pair in the LUT. The phase sector completion circuit is configured to determine whether the LUT has stored, for each of a plurality of phase sectors, a corresponding sine and cosine sample pair.

A motor driving unit controls motor conducted current of a brushed DC motor on the basis of a motor control signal. A motor control unit provides the motor control signal to the motor driving unit and thereby controls the brushed DC motor. A brush noise detecting unit detects brush noises in conducted current of the brushed DC motor and outputs a brush noise detection signal. A speed determining unit determines a time interval of the brush noises and determines a rotation speed of the brushed DC motor on the basis of the time interval. Further, the motor control unit determines whether the brushed DC motor is in a lock status or not on the basis of the rotation speed in a period that the motor control signal is provided to the motor driving unit to cause the brushed DC motor to be in operation.

A motor control apparatus includes a current estimation unit configured to output a detected current value corresponding to each of the three-phase AC currents based on the measured current value and rotor rotation angle information of the motor. The current estimation unit defines a phase whose duty ratio of a driving pulse supplied to an inverter circuit, which generates the three-phase AC currents, becomes more than or equal to an operation switching threshold as an estimation target phase, calculates, for the estimation target phase, an estimated current value based on a coefficient value, which is calculated from the measured current value by the current measurement unit in a period in which the duty ratio of the driving pulse is lower than the operation switching threshold, and the rotor rotation angle information, and outputs the calculated estimated current value as the detected current value of the estimation target phase.

A rotation direction detecting device has a current detector detecting the direction of current flowing through a motor, a voltage detector detecting voltages before and after the motor in a power supply line, and a rotation direction detector detecting the rotation direction of the motor based on the direction of the current and the voltages before and after the motor. The current detector is connected to points A, B before and after a shunt resistor, and detects the direction of the current flowing in the power supply line to form current direction information. The voltage detector is connected to points A, C before and after the motor, and detects the voltage at each position to form motor terminal voltage information. The rotation direction detector detects the rotation direction of the motor using a logical combination of the current direction information and the motor terminal voltage information.

A ripple detection device 10 includes: a current detection part 11 that outputs a variation in an armature current as a voltage variation signal; a first smoothing circuit block 12 that extracts a current ripple component and a noise component from the voltage variation signal and outputs a first smoothing signal S1; a gain adjustment part 13 that adjusts the amplitude of the first smoothing signal S1 and outputs an adjustment signal VCA; a second smoothing circuit block 14 that corrects distortion of the adjustment signal VCA and outputs a second smoothing signal S2; a ripple detection part 15 that extracts only the current ripple component from the second smoothing signal S2 by removing the noise component therefrom and outputs a ripple component signal S0; and a digital signal conversion part 16 that converts the ripple component signal S0 into a digital signal.

The life estimation system is a life estimation system that estimates a life of the reduction gear including a reduction mechanism. The life estimation system includes a sensor that is to be mounted onto the reduction gear and detects information for identifying a stress generated in a specific part of the reduction gear, and an estimating unit that identifies the stress generated in the specific part based on detection information obtained by the sensor and estimates the life of the specific part based on the identified stress.

A continuously rotating electric motor includes a rotor provided with permanent magnets and a stator formed by two coils in which, when the rotor is rotating, two induced voltage signals (U.sub.B1 and U.sub.B2) are respectively generated, which signals have an electric phase shift where 590, preferably 30<<65. The control device includes a circuit for detecting intersection times (T.sub.C) at which values of the two induced voltage signals are substantially equal. The control device is arranged to generate electric driving pulses to rotate the rotor, which are respectively initiated at initiation times determined by respective intersection times, and such that the electric driving pulses can be applied to the two coils arranged in series. Preferably, the control device is arranged such that the initiation times of the electric driving pulses occur directly after detections of corresponding intersection times.

A control system for controlling a mechanically commutated direct current electric motor and corresponding method of operation are provided. The control system includes a motor current sensing circuit for sensing a motor current comprising a plurality of ripples due to commutation of the motor and outputting a motor current signal. The control system also includes a controller including a finite state machine unit and is configured to detect the plurality of ripples in the motor current and to determine whether each of the plurality of ripples is a valid ripple using the finite state machine unit. The controller is also configured to count the plurality of ripples determined to be valid using the finite state machine unit and to determine at least one of a motor rotational position and a motor speed of the motor based on a quantity of the plurality of ripples determined to be valid.

Control logic for a power sharing system on a hybrid propulsion aircraft, utilizing parallel multiple control loops outputting difference commands which provide bumpless transfer between control loops without integrator wind up or reset logic, allowing for efficient load distribution between electric generators and batteries powering electric motors.

A computer implemented method for operating a wiper system of a sensor enclosure. The wiper system can be configured to receive a camera operating information from one or more cameras. The one or more cameras can be determined to be in an exposure mode based on the camera operating information. A first speed of one or more wipers can be adjusted such that the one or more wipers are not in field of views of the one or more cameras while the one or more cameras are in the exposure mode.