A closed-loop control device to control a system to be controlled includes a front node, back node, external tapping point, controller and compensating circuit. The compensating circuit has an inner node, frequency filter, front buffer and back buffer. The front node determines a difference; the back node supplies an external sum signal. A setting device automatically suppresses use of the output signal of the front buffer, supplies the back buffer and the back node with a first excitation signal as the compensation signal and detects a first result signal produced by the first excitation signal. The first result signal is one of the control difference, internal sum signal, output filtered signal of the frequency filter or output signal of the front buffer. The setting device evaluates the first excitation signal and the first result signal, sets a parameter of the frequency filter and the second propagation delay.

Methods and devices for diagnosing a robot. The method includes obtaining a first signal generated by a rotating component of the robot during operation of the robot. The first signal includes motion information of the rotating component. The first signal is preprocessed to filter out a part of the motion information in the first signal. The preprocessed first signal or spectrum information about the preprocessed first signal is sent to a server for diagnosing the robotU. A second signal is received from the server, wherein the second signal includes diagnostic information indicating whether a sub-component of the rotating component has a failure.

A diagnostic apparatus includes a receiving unit to receive context information defining an operation of a tool of a machine, rotation information of a spindle, tool information, and a detection result of a time-varying physical quantity generated by the tool; a frequency analysis unit to frequency-analyze the detection result; a range setting unit to set a frequency range; a bandwidth setting unit to set a bandwidth of a noted frequency band in the frequency range; a band pass filter setting unit to set a band pass filter using center frequencies and the bandwidth; a feature information extraction unit to extract feature information from the detection result using the band pass filter and a frequency analysis result of the detection result; and a determining unit to determine a machining state using the feature information. The center frequencies are set using the rotation information, the tool information, and the frequency range.

A machine motion trajectory measuring apparatus includes a three-axis acceleration sensor measuring acceleration of a motion-trajectory measurement subject and outputting the result as an acceleration sensor signal, a sensor signal separation unit separating the acceleration sensor signal into two or more frequency bands, a motor signal separation unit separating a detection position signal into the frequency bands identical to those of the sensor signal separation unit, a data calibration unit calibrating the acceleration sensor signal in each of the two or more frequency bands by using the acceleration sensor signal separated by the sensor signal separation unit and the detection position signal separated by the motor signal separation unit and obtaining a motion trajectory component in each of the two or more frequency bands, and a motion trajectory calculation unit coupling the motion trajectory components in the two or more frequency bands and outputting the result as a motion trajectory.

A closed-loop control device to control a system to be controlled includes a front node, back node, external tapping point, controller and compensating circuit. The compensating circuit has an inner node, frequency filter, front buffer and back buffer. The front node determines a difference; the back node supplies an external sum signal. A setting device automatically suppresses use of the output signal of the front buffer, supplies the back buffer and the back node with a first excitation signal as the compensation signal and detects a first result signal produced by the first excitation signal. The first result signal is one of the control difference, internal sum signal, output filtered signal of the frequency filter or output signal of the front buffer. The setting device evaluates the first excitation signal and the first result signal, sets a parameter of the frequency filter and the second propagation delay.

Methods and devices for diagnosing a robot. The method includes obtaining a first signal generated by a rotating component of the robot during operation of the robot. The first signal includes motion information of the rotating component. The first signal is preprocessed to filter out a part of the motion information in the first signal. The preprocessed first signal or spectrum information about the preprocessed first signal is sent to a server for diagnosing the robotU. A second signal is received from the server, wherein the second signal includes diagnostic information indicating whether a sub-component of the rotating component has a failure.

A machine motion trajectory measuring apparatus includes a three-axis acceleration sensor measuring acceleration of a motion-trajectory measurement subject and outputting the result as an acceleration sensor signal, a sensor signal separation unit separating the acceleration sensor signal into two or more frequency bands, a motor signal separation unit separating a detection position signal into the frequency bands identical to those of the sensor signal separation unit, a data calibration unit calibrating the acceleration sensor signal in each of the two or more frequency bands by using the acceleration sensor signal separated by the sensor signal separation unit and the detection position signal separated by the motor signal separation unit and obtaining a motion trajectory component in each of the two or more frequency bands, and a motion trajectory calculation unit coupling the motion trajectory components in the two or more frequency bands and outputting the result as a motion trajectory.