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Surface cleaning has always been an important procedure to improve quality and performance of final components in modern industrial manufacturing. Among various surface cleanings, laser cleaning has been identified as the most promising green cleaning technology to replace conventional mechanical and chemical cleaning. Laser cleaning is a green cleaning technology that will not result in environmental pollution. And, laser cleaning is a versatile, precise, and controllable technology. A set of laser cleaning system that consists of line structured light and industrial manipulator, was designed in this paper. The line structured light, combined with camera, was used to scan workpiece surface and reconstruct the 3D model of workpiece surface. The industrial manipulator was utilized to perform scanning and cleaning movements. This new system is called Laser Cleaning Robot (LCR). To improve automation level and cleaning efficiency of the LCR, a path generation method based on line structured light and industrial manipulator was proposed in this paper. Experimental results demonstrate the performance of the proposed method in terms of cleaning efficiency for large-scale workpiece.

Surface cleaning is an essential procedure to improve quality and performance of workpiece in modern industrial manufacturing. Among surface cleaning technologies, laser cleaning has been regarded as the most promising green cleaning technology. Laser cleaning is a green cleaning technology that will not cause any environmental pollution. Laser cleaning has the ability of cleaning the area of the designated shape. A set of laser cleaning system that consists of two-dimensional galvanometer and 3-axis motion platform, was designed in this paper. The two-dimensional galvanometer was used to clean the area of the specified shape. The 3-axis motion platform expands the limited cleaning area of the two-dimensional galvanometer to a larger area. Laser displacement sensor is utilized to ameliorate the cleaning quality. To improve the cleaning accuracy of the system proposed in this article, a camera was adopted to recognize the origin of the workpiece and correct the pose of the workpiece. Experimental results demonstrate the performance of the proposed system for large-scale plane workpiece.

Chromatic confocal point sensors are used to measure the high-precision surface distance, and it’s based on the theory of chromatic dispersion and encodes the distance between the measure surface and chromatic lens. By accurately measuring the wavelength value, it indirectly calculates the distance to object surface. The accuracy of the sensor depends on the chromatic range of the lens and the resolution of the spectrograph. In this paper, the algorithm of spectral peak positioning can effectively filter kinds of noise, such as spectrometer and light source. The spectral data signal peak is extracted by Gaussian fitting method. In practice, the wavelength position can be stably detected effectively.

During the process of collecting laser bath temperature data by CCD industrial camera, due to the influence of laser cladding process and installation location of mechanical equipment, the lens axis of CCD industrial camera is not perpendicular to the surface of the molten pool, resulting in positioning error caused by tilting photography. In order to eliminate the influence of positioning error and restore the true shape of the molten pool, a position calibration method for the temperature image of molten pool based on image processing technology was proposed. The experimental results show that after image processing the acquired image data of the molten pool was restored image morphology, which laid the foundation for subsequent image processing.

The fundamental shear horizontal(SH0) wave has several unique features that are attractive for long-range nondestructive testing(NDT). By a careful design of the geometric configuration, electromagnetic acoustic transducers(EMATs) have the capability to generate a wide range of guided wave modes, such as Lamb waves and shear-horizontal(SH) waves in plates. However, the performance of EMATs is influenced by their parameters. To evaluate the performance of periodic permanent magnet(PPM) EMATs, a distributed-line-source model is developed to calculate the angular acoustic field cross-section in the far-field. Numerical analysis is conducted to investigate the performance of such EMATs with different geometric parameters, such as period and number of magnet arrays, and inner and outer coil widths. Such parameters have a great influence on the directivity of the generated SH0 waves that arises mainly in the amplitude and width of both main and side lobes. According to the numerical analysis, these parameters are optimized to obtain better directivity. Optimized PPM EMATs are designed and used for NDT of strip plates. Experimental results show that the lateral boundary of the strip plate has no perceivable influence on SH0-wave propagation, thus validating their used in NDT. The proposed model predicts the radiation pattern of PPM EMATs, and can be used for their parameter optimization.