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In this study, a laser interferometric sensing measurement (ISM) system based on a 4R manipulator system is developed to achieve detection of mechanical targets, which aims to realize the real-time, online detection of workpieces with high precision during processing. The 4R mobile manipulator (MM) system is flexible and can move in the workshop, aiming to preliminarily track the position of the workpiece to be measured and locate it at millimeter level. The reference plane of the ISM system is driven by piezoelectric ceramics with the spatial carrier frequency realized and the interferogram obtained by a charge coupled device (CCD) image sensor. The subsequent processing of the interferogram includes fast Fourier transform (FFT), spectrum filtering, phase demodulation, tilt elimination for wave-surface, etc., so as to further restore the surface shape of the measured surface and obtain the surface quality indexes. A novel cosine banded cylindrical (CBC) filter is used to improve the FFT processing accuracy, and a bidirectional extrapolation and interpolation (BEI) technique is proposed for the preprocessing operation of real-time interferograms before FFT processing. Compared with the results from a ZYGO interferometer, the real-time online detection results show the reliability and practicability of this design. The relative error of peak–valley value reflecting the processing accuracy can reach about 0.63%, with the root-mean-square value reaching about 1.36%. Some possible applications of this work include the surface of mechanical parts in the process of online machining, the end face of shaft-like structures, annular surfaces, etc.

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Aiming at the problem of system vibration during yawing of large wind turbines, the mathematical model is obtained by simulating the structure model of the yawing system, which is then represented by a general free vibration equation. The system vibration equation is modeled and simulated by MATLAB/Simulink. The model is controlled by PID, Fuzzy PID and Optimal Fuzzy PID intelligent algorithm, and the control result is obtained. By comparing the control results between different algorithms, it can be shown that although the PID algorithm and the Fuzzy PID algorithm can obviously and effectively control the vibration model of the yaw system, and the control effect of the Fuzzy PID algorithm is better than that of the PID algorithm, the PID parameters obtained by the “trial and compact method” are not the optimal parameters, which will affect the control effect of the Fuzzy PID. The Optimal Fuzzy PID algorithm can automatically optimize by MATLAB program to obtain the optimal PID parameters and achieve the optimal control effect.

Absrtact. The system development of the mobile robot mainly includes two parts: one is to build a laser interference system based on piezoelectric ceramic dynamic carrier; The other part is the image processing of the interference fringe pattern collected by the interference system. The laser interference system can be installed on the front-end manipulator of the robot as an integral structure. The shape information of the measured micro-surface can be obtained by processing the interference fringes collected by the image acquisition card on the interference system, so as to achieve the purpose of high-precision surface roughness measurement.