Papers by Author: Bing Li

Abstract: In order to filter the impulse noise existing in the weld surface defect images, the traditional median filtering will dim image, even destroy some details in the image, We put forward a new filtering algorithm based on dual threshold Criterion. This way distinguishes the noise point and signal location in the first, and it only doing median filter to the noise point. Lastly, it solves the image’s boundary. We can find it when compared to the traditional median filtering and modified extremum median filtering, the way in this article can be good for filtration, and can keep the image’s details, which have obvious advantage.

Abstract: Because the fusion rules which are based on coefficient of a single point and coefficient of region has one-sidedness and are easy to make blending images lack fidelity, a new fusion rule is put forward. When this fusion rule fuses the low frequency sub-band resolved by wavelet method, it adequately consider the local areas regional energy and the regional energys similarity of the image which is need to fuse, and it use threshold to choose appropriate fusion rule. Experimental result indicated that this way can preferably keep detail features of the image, and it has some engineering application value.

Abstract: In the light of the shortcoming that gears traditional measurement methods not only consume time and labor, but also have a great contrived factor, a new methods of total accumulative pitch errors measurement based on the coordination measurement machine is put forward, which can scan tooth profile coordinates automatically and quickly within the effective work scope of tooth profile, conduct the data processing directly and obtain the deviation through the involutes deviation to achieve online measurements. The theoretical analysis and experimental results show that the measurement method has many advantages, such as simple, non-contact and efficient.

Abstract: The kind and extent of defect can be identified through image processing. First, the weld defect detection device should be constructed, and then the defect imaged should be obtained through rational way, in order to enhance the image quality, image filter and image enhancement method should be use. To ensure the real-time system, the weld region need to segment from the image. After that, the needed defect features need to determine and extract. Finally, the kind, the location and the size of the defect can be defined.

Abstract: In the conditions of rationally selecting of the measure tooth number, this paper puts forward a new method to calculate the common normal length variation, which is based on coordinate measurement machine to collect the data of bilateral modification gear's outline. Firstly, the addendum modification coefficient and tangential modification coefficient are used to determine the optimum measure tooth number, and then the common normal length variation is determined according to the definition. The experiment has shown that this way has a lot of advantages, such as the intensive data of sample points, less human intervention and high measurement accuracy.

Abstract: The structure of a 3-DOF parallel manipulator is presented. The methodologies of multiple-mode negative impulses input shaping is introduced, which can decrease the delay time of the system response while the residual vibration is suppressed. The parameters of two-mode negative impulses and positive impulses input shapers of the 3-DOF manipulator are presented. The sensitivity analysis of these input shapers are carried out through numerical simulations, and the robust of the input shapers are presented and compared.

Abstract: A lot of lubricating oil is consumed in the process of the cold rolling of stainless steel. The oil recovery is very important due to some reasons, such as the cost of production and environmental pollution. A set of lubricating oil recovery system is designed and constructed, which is equipped with a set of expanded size recovery oil pan for recycling splashed oil, a high efficiency two-level mist recovery system for recycling the oil mist, and an oil collection platform for recycling the oil rolled. The system is effectively to recovery more of lubricating oil through actual use and measurement.

Abstract: Vibration characteristics of the thin-walled cylindrical pipe are affected by the liquid within the pipe. The natural frequencies and vibration modes of the pipe without liquid are analyzed by the theory of beam bending vibration and finite element model, which is based on the Timoshenko beam model. The first three natural frequencies and vibration modes of the pipe with or without liquid are acquired by experiments. As shown in the experiment results, the natural frequencies of the containing liquid pipe are lower than the natural frequencies of the pipe without liquid.

Abstract: A variable gear measuring method was put forward in order to define the error of eccentricity of the zero-tooth-difference internal gear, which was based on the three-coordinate measuring machine. This method can scan the coordinate of tooth profile automatically and fleetly, then by calculating the difference of the tooth profile curve between the theory and reality, and achieving the measure on line about geared ring radial runout to define the error of eccentricity. The results of this experiment and theoretic analysis showed that the method which was putted forward has many advantages, like the density of sampling is big, the calculation is simple, the measure is accurate, and the human factors are very little.

Abstract: The methodologies and application of multiple-mode negative impulses input shaping of a 3-DOF parallel manipulator with flexible intermediate linkages are presented in this paper. First, the structural system and the dynamic equations are expressed for a 3-DOF manipulator. Second, the multiple-mode negative impulses input shaping is introduced to reduce the residual vibration of the multiple-mode system and decrease the delay time of the system response at the same time. Finally, the theory of the multiple-mode ZV, ZVD and EI negative impulses input shapers are presented, and the two-mode negative impulses input shapers of a 3-DOF manipulator are established and compared with the positive impulses input shapers.