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Image-based registration methods have been widely used in augmented assembly systems. However, many challenges remain to be solved, such as low robustness and poor timeliness during registration. This paper presents a deep learning approach for registration. To reduce the workload of data collection, an automatic picture generation method is offered for deep learning algorithm, and a dataset is built for detecting the keypoints of assembly objects. We propose a fully convolutional network (FCN) model for detecting keypoints from a single RGB image. The FCN model, which consists of 13 layers, can accurately detect the location of keypoints with a low computational resource consumption. The detected keypoints are used to solve the camera position and orientation for augmented assembly registration. The experiments demonstrate that our method is robust against different rotation angles of the assembly object and against background interference. The detection accuracy is high under different camera motion blurs; to be specific, the pixel error in different directions of 640 × 480 images was only 0.9 pixels. The FCN-based registration approach was shown to be fast during augmented assembly experiments, achieving up to 30 FPS.

Charge compensation on anionic redox reaction (ARR) has been promising to realize extra capacity beyond transition metal redox in battery cathodes. The practical development of ARR capacity has been hindered by high-valence oxygen instability, particularly at cathode surfaces. However, the direct probe of surface oxygen behavior has been challenging. Here, the electronic states of surface oxygen are investigated by combining mapping of resonant Auger electronic spectroscopy (mRAS) and ambient pressure X-ray photoelectron spectroscopy (APXPS) on a model LiCoO

Constructions of high-energy-density lithium-ion batteries (LIBs) largely rely on the breakthrough of cathode materials. In contrast to conventional layered oxide cathodes (LiTMO2, TM denotes transition metal), invoking oxygen redox by increasing the chemical ratio of Li/O in oxide cathode can further boost the development of new types of high-capacity cathodes which theoretically enable the realization of LIBs of above 400 Wh/kg and are even attainable for 600 Wh/kg, meeting the future demands of various application scenarios for high energy density, such as electrical aircraft. However, the revolution of high-capacity cathodes is far from the realistic elevation of cell-level energy density and their practical applications in LIBs, which involves the considerations of other indispensable metrics in terms of both materials and technologies. Therefore, in this perspective, an in-depth discussion from fundamentals to applications of oxygen-based cathode materials is provided. First, we briefly summarized the representative investigations on oxygen redox mechanisms. Moreover, intrinsic properties of materials based on oxygen redox are multidimensionally evaluated. Furthermore, cell-level gravimetric energy density, potentials for practical applications, and possible design strategies are critically analyzed.

Developing low-cost and efficient oxygen electrocatalysts for oxygen reduction and evolution reaction (ORR&OER) is critical for various energy conversion technologies. Herein, we report an arc discharge strategy coupled with an controllable oxidation to prepare Co/Co3O4 nanoparticles confined in ultrathin O-doped graphitic carbon layer (Co/Co3O4@ODGC) as highly active bifunctional oxygen electrocatalysts for Zn-air batteries (ZABs). The resultant Co/Co3O4@ODGC shows an impressive ORR performance with a half-wave potential of 0.80 V in 0.1 M KOH. It also exhibits remarkable OER performance with a small overpotential of 300 mV to reach a current density of 10 mA cm−2. Both experimental studies and theoretical calculations indicate that the high ORR and OER activities are attributed to the synergistic electronic effect between the Co/Co3O4 heterostructures and ultrathin O-doped graphitic layer (~1.5 nm). Particularly, the electron redistribution in graphitic layer caused by O-doping and carbon defects significantly decreases the energy barrier for oxygen adsorption/desorption. More attractively, the as-constructed ZABs with Co/Co3O4@ODGC cathode show an impressive open voltage (1.60 V), a high power density of 107 mW cm−2, and good stability without nearly no performance decay for 40 h at 2.0 mA cm−2. This work provides both fundamental understanding and easy strategy for developing the efficient bifunctional oxygen electrocatalysts for high performance metal-air batteries.