Discharge area segmentation of power equipment in UV image based on GVF snake model

The dynamic transmission characteristics and the sensitivities of the three stage idler gear system of the new NC power turret are studied in the paper. Considering the strongly nonlinear factors such as the periodically time-varying mesh stiffness, the nonlinear tooth backlash, the lump-parameter model of the gear system is developed with one rotational and two translational freedoms of each gear. The eigen-values and eigenvectors are derived and analyzed on the basis of the real modal theory. The sensitivities of natural frequencies to design parameters including supporting and meshing stiffnesses, gear masses, and moments of inertia by the direct differential method are also calculated. The results show the quantitative and qualitative impact of the parameters to the natural characteristics of the gear system. Furthermore, the periodic steady state solutions are obtained by the numerical approach based on the nonlinear model. These results are employed to gain insights into the primary controlling parameters, to forecast the severity of the dynamic response, and to assess the acceptability of the gear design.

To extract the discharge region contour of the ultraviolet(UV) image may help us to locate the discharge position, to obtain the appearance and the size, furthermore, it help us to analysis and judge the equipment defect. In this paper, a GVF(Gradient Vector Flow) snake model method is applied to obtain the discharge region contour, this method diffuses the traditional snake model's force field, so it can guide the initial curve to shrink or expand to the real boundary automatically. The method has the character of fast convergence speed, not sensitive to the initial contour, and the initial curve can converge to the convex-concave part of discharge region. Experiments show that the discharge region boundary extracted by GVF snake method is continuous, good smoothness, near to the real edge of discharge region, and it also has a good anti-noise ability.