Abstract:
An angle-calculation apparatus for three-phase optical encoder receives three-phase sinusoidal signals 120 degree phase from the optical encoder and obtains angle information for a motor rotor. The angle-calculation apparatus includes an A/D converter, a digital signal processor (DSP), a phase digitalizer and a digital counter. The A/D converter converts three-phase analog signals of the optical encoder into three-phase digital signals. The phase digitalizer converts the three-phase analog signals into digital phase signals. The digital counter generates a counting value based on the digital phase signals. The DSP performs an inverse trigonometric function calculation on a relatively linear region of the three-phase digital signals to obtain the angle information. The DSP obtains the rotation turn number and rotation direction of the motor rotor according to the counting value.
Abstract:
A high-precision absolute type encoder apparatus includes a controller electrically connected to an incremental type encoder and generating a control signal to the incremental type encoder, a comparator electrically connected to outputs of the incremental type encoder and generating first pulse signals, a latch unit electrically connected to outputs of the comparator and generating second pulse signals by latching the generating first pulse signals. When power failure occurs, the controller generates the control signal as successive pulses with predetermined period to drive the latch unit and the incremental type encoder. Therefore, the controller knows angular information of the incremental type encoder by counting the second pulse signals. The absolute angular information can be obtained by combining the angular information and an initial position after power failure.
Abstract:
A wire-saving optical encoder having servomotor identification information is applied to a wire-saving transmission design to provide a circuit and a method for processing servomotor identification information and encoded feedback control signals. With a microprocessor, a multiplexer and the servomotor identification information stored in the microprocessor, an output device and a driver for the feedback signals of the encoder constitute a wire-saving signal transmitting circuit. The microprocessor and multiplexer switch a signal transmission mode to transmit the servomotor identification information and phase change signal produced by the servomotor control parameters stored in a firmware by a serial output mode, and the same transmitting wire is used to transmit a rotor operating signal after the transmitting mode is switched, so as to save wires and lower costs for transmitting feedback signals and correctly identifying and effectively controlling a servomotor.
Abstract:
An early-warning apparatus for health detection of a servo motor and a method for operating the same are applied to estimate vibration phenomenon of a CNC tool machine. First, a vibration signal is produced through a vibration detecting unit. Afterward, the vibration signal is sequentially sent to a data buffer. Afterward, the vibration signal is transformed in time and frequency domains through a time-frequency transforming unit. Finally, a deterioration index is calculated through a deterioration index calculating unit to obtain a health index which is calculated through a health index calculating unit. Therefore, the build-in vibration detecting unit is provided to dispense with additional external sensors. Furthermore, the vibration phenomenon of the servo motor of the CNC tool machine is estimated according to the health index, thus analyzing non-linear and non-stationary characteristics of the estimated vibration phenomenon.
Abstract:
An optical encoder includes a controller electrically connected to an optical sensor to discriminate displacement information of a glass disc. The controller comprises a pair of analog amplifiers for amplifying quadrature periodical output signals of the optical sensor, a pair of A/D converters electrically connected to the analog amplifiers for digitalizing the output of the analog amplifiers, a pair of hysteresis comparators electrically connected to the optical sensor for performing hysteresis comparison for the output of the optical sensor, an up/down counter electrically connected to the pair of hysteresis comparators for up/down counting the output of the hysteresis comparators and a firmware unit electrically connected to the pair of A/D converters and the up/down counter for performing interpolation for the quadrature periodical output signals and counting for the hysteresis compared signals. Therefore, optical encoded result of higher resolution can be achieved.
Abstract:
A method for modifying a porous substrate, including: coating a metal hydroxide layer on a porous substrate; and calcining the porous substrate with the metal hydroxide layer coated thereon to transform the metal hydroxide layer into a continuous metal oxide layer, forming a modified porous substrate. The disclosure also provides a modified porous substrate.
Abstract:
The present invention provides a method for guiding a pick-up head to follow an information track. The method comprises the steps of sensing and sending notification of displacement between the pick-up head and the center of the information track, generating a first correction directly proportional to the displacement, generating from the first correction a second correction non-proportional to the displacement, generating a third correction from an amplified tracking error signal and generating a driving force proportional to the sum of the second and third corrections, driving the pick-up head to follow the information track.
Abstract:
A method of fabricating a porous media is provided. In the method, a metal mesh is provided. The metal mesh includes interlaced metal wires, and first holes are formed among the metal wires. An area of each first hole ranges from 1 μm2 to 10,000 μm2, and an area error between the first holes is less than 5%. A metal layer covers the metal wires, so as to form the porous media with second holes. By controlling the thickness of the metal layer, an area of each second hole is reduced to 0.01 μm2 to 1 μm2, and an area error between the second holes is less than 5%.
Abstract:
An early-warning apparatus for health detection of a servo motor and a method for operating the same are applied to estimate vibration phenomenon of a CNC tool machine. First, a vibration signal is produced through a vibration detecting unit. Afterward, the vibration signal is sequentially sent to a data buffer. Afterward, the vibration signal is transformed in time and frequency domains through a time-frequency transforming unit. Finally, a deterioration index is calculated through a deterioration index calculating unit to obtain a health index which is calculated through a health index calculating unit. Therefore, the build-in vibration detecting unit is provided to dispense with additional external sensors. Furthermore, the vibration phenomenon of the servo motor of the CNC tool machine is estimated according to the health index, thus analyzing non-linear and non-stationary characteristics of the estimated vibration phenomenon.
Abstract:
An angle-calculation apparatus for three-phase optical encoder receives three-phase sinusoidal signals 120 degree phase from the optical encoder and obtains angle information for a motor rotor. The angle-calculation apparatus includes an A/D converter, a digital signal processor (DSP), a phase digitalizer and a digital counter. The A/D converter converts three-phase analog signals of the optical encoder into three-phase digital signals. The phase digitalizer converts the three-phase analog signals into digital phase signals. The digital counter generates a counting value based on the digital phase signals. The DSP performs an inverse trigonometric function calculation on a relatively linear region of the three-phase digital signals to obtain the angle information. The DSP obtains the rotation turn number and rotation direction of the motor rotor according to the counting value.