A servo control device for controlling a motor based on a position command when an operation target is connected to the motor via a wave gear reduction mechanism may include a position control system configured to detect a shaft angular position of the motor to perform a closed-loop control based on the shaft angular position; an inverse control element having an inverse characteristic of dynamics of the position control system; and a compensation amount generation unit configured to generate a compensation amount for compensating for an angular transmission error of the wave gear reduction mechanism. The inverse control element is configured to apply compensation amount to the position control system.

A servo control device for controlling a motor based on a position command when an operation target is connected to the motor via a wave gear reduction mechanism may include a position control system configured to detect a shaft angular position of the motor to perform a closed-loop control based on the shaft angular position; an inverse control element having an inverse characteristic of dynamics of the position control system; and a compensation amount generation unit configured to generate a compensation amount for compensating for an angular transmission error of the wave gear reduction mechanism. The inverse control element is configured to apply compensation amount to the position control system.

Control commands for a control device of a machine define a sequence of successive sections of ideal position target values for a position-controlled shaft of the machine. The ideal position target values either increase or decrease monotonically within the sections, but the direction of the monotony changes from section to section. A position controller determines actuating signals for an actuator from position target values resulting from ideal position target values, additional target values and position actual values. Within sections, the additional target values are positive (negative) when the ideal position target values increase (decrease) monotonically. The additional target values have a first component dependent exclusively on a position difference, with the magnitude of the first component increasing as the magnitude of the position difference increases, first strictly monotonically and then at least monotonically.

An inverter converts direct-current power to alternating-current power by operations of a plurality of switching elements under a PWM control, and supplies the alternating-current power to an alternating-current electric motor. A feedback control computation unit of an inverter control unit uses current values acquired from current sensors detecting a current flowing to the alternating-current electric motor and a rotation angle of the alternating-current electric motor to perform a control computation in a (N/2) cycle (N is a natural number) of a triangular wave carrier of the PWM control. At the acquisition of the current values detected by the current sensors, an average acquisition unit acquires an average of current values in a carrier half cycle as a period between a peak and a valley of the carrier, or acquires a current value regarded as an average of the current values at an acquirable timing.

An inverter converts direct-current power to alternating-current power by operations of a plurality of switching elements under a PWM control, and supplies the alternating-current power to an alternating-current electric motor. A feedback control computation unit of an inverter control unit uses current values acquired from current sensors detecting a current flowing to the alternating-current electric motor and a rotation angle of the alternating-current electric motor to perform a control computation in a (N/2) cycle (N is a natural number) of a triangular wave carrier of the PWM control. At the acquisition of the current values detected by the current sensors, an average acquisition unit acquires an average of current values in a carrier half cycle as a period between a peak and a valley of the carrier, or acquires a current value regarded as an average of the current values at an acquirable timing.

Disclosed herein are a motor control apparatus and method. The motor control apparatus includes a compensation signal generator configured to apply a DC-Link voltage (V.sub.Link) for driving a motor to a parameter map preset in order to estimate a gain and phase of a motor torque ripple generated when the motor is driven according to a motor command current and a motor rotation speed, and to generate a compensation signal (i.sub.comp) for compensating for the motor torque ripple corresponding to a current input motor command current (i.sub.q*), motor rotation speed (ω.sub.m), and DC-Link voltage (V.sub.Link), and a current controller configured to control the current of the motor by controlling an inverter such that a compensation command current (i.sub.q*_.sub.comp), generated by reflecting the compensation signal (i.sub.comp), in the motor command current (i.sub.q*), coincides with a motor drive current (i.sub.q) supplied to the motor from the inverter.

A rotary machine device configured to contact with an external object is provided. The rotary machine device includes a rotary motor, a first encoder, a fixed housing, a fixed shaft, an output shaft and a second encoder. The rotary motor includes a motor housing and an exerting shaft. As the rotor of the motor housing rotates for a rotation angle, the rotor drives the exerting shaft to rotate for an exerting angle. The first encoder detects the rotation angle of the rotor. The output shaft includes an elastomer and is inserted in an accommodation hole of the fixed shaft. The elastomer is penetrated through the output shaft and is connected to the exerting shaft. The second encoder includes a disk and a sensor disposed on the exerting shaft and the fixed shaft respectively. The sensor detects the exerting angle of the exerting shaft through the disk.

A display including a supporting stand and a display panel is provided. The supporting stand has a rotating assembly, a drive motor, and a microcontroller. The display panel has a computing device. The drive motor is connected to the rotating assembly for driving the rotating assembly to rotate. The microcontroller is coupled to the drive motor for controlling the drive motor. The display panel is disposed on the rotating assembly. The computing device is coupled to the microcontroller. The computing device is configured to read an image. The computing device transmits a signal to the microcontroller based on an orientation of the image being portrait or landscape so that the microcontroller switches on the drive motor and the rotating assembly drives the display panel to rotate relative to the supporting stand for switching a rotating position of the display panel to a portrait mode or a landscape mode.

In accordance with at least one aspect of this disclosure, a system includes, a servo configured to control a position of a valve, a driver operatively connected to control movement of the servo, a control module operatively connected to control the driver, can configured to control the driver with pulse width modulated output to control a frequency of a generator through movement of the servo.

A shift range control apparatus acquires a motor rotation angle signal corresponding to a rotation position of a motor, calculates a motor angle based on a motor rotation angle signal, acquires an output shaft signal corresponding to the rotation position of an output shaft, sets a target rotation angle based on a target shift range and the output shaft signal, drives the motor to cause the motor angle to reach the target rotation angle, determines the shift range based on the output shaft signal, monitors a fault in the output shaft signal, and learns a P-side reference position corresponding to the motor angle in a situation where the engagement member abuts against a first wall portion of the shift range switching mechanism, in a condition that the fault occurs in the output shaft signal.