No abstract

PurposeThe purpose of this paper is to develop a kind of low cost measuring system based on binocular vision sensor to detect both the weld pool geometry and root gap simultaneously for robot welding process.Design/methodology/approachTwo normal charge coupled device cameras are used for capturing clear images from two directions; one of them is used to measure the root gap and another one is used to measure the geometric parameters of the weld pool. Efforts are made from both hardware and software aspects to decrease the strong interferences in pulsed gas tungsten arc welding process, so that clear and steady images can be obtained. The grey level distribution characteristics of root gap edge and weld pool edge in images are analyzed and utilized for developing the image processing algorithms.FindingsA solid foundation for seam tracking and penetration control of robot welding process can be established based on the binocular vision sensor.Practical implicationsThe results show that the algorithms can extract the root gap edges and the contour of weld pool effectively, and then some geometric parameters can be calculated from the results.Originality/valueThe binocular vision system provides a new method for sensing of robot welding process.

The CK bond plays a significant role in stabilizing the Na‐K (NaK) alloy electrodes due to the enhancive interfacial affinity. In this study, a method for constructing semi‐solid K metal electrodes with rich CK bonds by in situ replacement of N‐doped carbon nanotubes (CNT) and liquid NaK alloy is proposed. Based on the in situ infrared thermal imaging technique combined with heat calculation, X‐ray photoelectron spectroscopy elemental analysis, and reaction thermodynamic calculation, graphite‐N, which is widely distributed on the wall of CNT, offers plenty of replacement sites for forming CK bonds. Due to the rich bonds, the amount of CNT sharply reduces in dendrite‐free semi‐solid CNT@NaK electrodes and the activity of NaK alloy raises to ≈90%. This discovery provides a new idea for establishing dendrite‐free anodes for K metal batteries.

No abstract

No abstract