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This paper aims to provide a posture generation method of robot deposition paths based on intersection topology, which is helpful to contribute to improving the flexibility and deposition capability of the deposition system.

Via the geometry information and normal vector information of the stereolithography (STL) model, the intersecting edge information is generated and the topological relationship of the model is established. Through the removal of redundant points for the STL model and the sort of robot path points, the position information of robot path points is obtained. According to the geometric relationship between the normal vector information of the STL model and the robot deposition path points, combining with the robot posture representation method of roll-pitch-yaw angles, the posture information of path points is achieved. Then, the generation from CAD model of parts to robot paths for laser melting is realized, and the experimental verification is carried out.

For simple parts, the laser melting process can be completed without the posture information of deposition paths. However, in the melting process of a turbine blade, there are some accumulated burls on the sidewall. The posture generation method of robot deposition paths based on the intersection topology can solve this problem. The light spot of deposition points irradiates on the surface of the forming part, and the forming process can proceed smoothly.

As a motion platform in laser melting deposition (LMD), the application of the multi-joint robot can improve the flexibility and deposition capability of the deposition system, as well as promote the LMD application for individuation manufacturing, parts repair and green remanufacturing.

The posture is essential for robot deposition paths. This paper first proposes a posture generation method of deposition paths for LMD to improve the flexibility and deposition capability of LMD systems.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics and publications of other similar research bodies as issued

Online systems are presented as new tools in the hands of scientific policy makers. When new research proposals require comparative assessment, these systems provide an objective criterion for evaluating both the previous work of a given group and the timeliness and originality of a proposed project. Three examples are presented: (i) evaluation of a determinate project taking into account geographic, disciplinary and historical areas and the results and applications up to the present, (ii) evaluation of a Spanish research team in Physics and (iii) evaluation of a Spanish periodical connected with food research.

The purpose of this paper is to investigate the effect of different soldering temperatures on the performance of chip-on-board (COB) light sources during vacuum reflow soldering.

First, the influence of the void ratio of the COB light source on the steady-state voltage, luminous flux, luminous efficiency and junction temperature has been explored at soldering temperatures of 250°C, 260°C, 270°C, 280°C and 290°C. The COB chip has also been tested for practical application and aging.

The results show that when the soldering temperature is 270°C, the void ratio of the soldering layer is only 5.1%, the junction temperature of the chip is only 76.52°C, and the luminous flux and luminous efficiency are the highest, and it has been observed that the luminous efficiency and average junction temperature of the chip are 107 lm/W and 72.3°C, respectively, which meets the requirements of street lights. After aging for 1,080 h, the light attenuation is 84.64% of the initial value, which indicates that it has higher reliability and longer life.

It can provide reference data for readers and people in this field and can be directly applied to practical engineering.