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According to the surface reflection characteristics of carbon fiber reinforced plastics and the geometric characteristics of aircraft panel parts, a robot automatic measurement system based on line laser scanning is designed. The selection criteria of measurement pose and the pre-calibration method of measurement pose based on a laser tracker are given. A 3D reconstruction method of global stitching of large-scale parts based on pre-calibration measurement pose is proposed, Finally, the correctness and effectiveness of the proposed method are verified by measuring typical samples with a prototype system.

Sparse code multiple access (SCMA) is able to provide high spectral efficiency and massive connectivity, hence it is considered as a promising scheme for the fifth generation (5G) systems. This paper proposed a radio resource allocation scheme based on deep learning for SCMA systems, with the aim to automatically avoid the inter-cell interference. A long short term memory (LSTM) network is adopted to learn the past interference characteristics and predict the interference power in the current subframe. Radio resource blocks with less predicted interference power are then selected for users to transmit signals. Simulation results show that the proposed scheme outperforms the moving average prediction method and has significant gains over the random radio resource block allocation in terms of achievable bit error rate in SCMA systems.

In this experiment, a method for continuous detection of Fe3+ and F- based on the fluorescence “OFF-ON” of quinine sulfate was designed. Through the addition of Fe3+, the fluorescence spectrum of quinine sulfate appeared “OFF”. Then, when F- was added, the fluorescence appeared “ON” again. By this method, we can get the quantitative detection of Fe3+ and F- continuously. The detection limit of Fe3+ is 1.0×10-5 mol/L and the linear range is 4×10-5 mol/L-8×10-4 mol/L. The detection limit of F- is 4.4×10-5 mol/L and the linear range is 1.2×10-4 mol/L-2.4×10-3 mol/L.

In order to promote the application of raindrop-shaped flow tube valveless piezoelectric pump (RSFTV PZT pump), basing on the existing research, the RSFTV PZT pump was simulated by computer. Firstly, the existence of the flow resistance of the flow tube was proved by simulation of FLUENT. Then, the dynamic mesh analysis of the pump was carried out to simulate the pumping flow rate at different driving frequencies. Lastly, the simulated results were compared with the experimental results, which shows that the flow rate tendency and value obtained by simulation are basically consistent with that by experiment. The simulation of the RSFTV PZT pump would be helpful to further accelerate related researches and promote the application of RSFTV PZT pump in MEMS and other fields.

Fused deposition modeling, as one of the most widely used types of 3D printing, is undoubtedly a good method when it comes to personalizing custom production and producing some complicated parts which cannot be machined by cutting tools. However, existing FDM printers are restricted to printing only monochrome objects due to the poor mixing quality and nozzle blockage caused by the irrational structure of nozzle. In this paper, the 3D model of the color mixing nozzle is designed by SolidWorks software at first. Second, the temperature field and the stress field are simulated by using ANSYS software. Comparing the simulation results, the main reason for the blockage at the notch of the throat pipe is revealed. Some other design flaws, including the position of the thermistor, the shape of the flow channel and the material selection of each component, are found out and optimally modified. Finally, the nozzle is optimized, and the rationality of the optimization design is verified by thermal-mechanical coupling field analysis. The problem of nozzle blockage in the printing process is settled, and the printing quality and stability are significantly improved.

A novel traveling wave piezoelectric-actuated tracked mobile robot with potential application to robotic rovers was proposed and investigated in this study. The proposed tracked mobile robot is composed of a parallelogram-frame-structure piezoelectric transducer with four rings and a metal track. Utilizing the converse piezoelectric and friction effects, traveling waves were propagated in the rings and then the metal track was actuated by the piezoelectric transducer. Compared with traditional tracked mechanisms, the proposed tracked mobile robot has a simpler and more compact structure without lubricant, which eliminates the problem of lubricant volatilization and deflation, thus, it could be operated in the vacuum environment. Dynamic characteristics were simulated and measured to reveal the mechanism of actuating track of the piezoelectric transducer. Experimental investigations of the traveling wave piezoelectric-actuated tracked mobile robot were then carried out, and the results indicated that the robot prototype with a pair of exciting voltages of 460 Vpp is able to achieve a maximum velocity of 57 mm s−1 moving on the foam plate and possesses the obstacle crossing capability with a maximum height of 27 mm. The proposed tracked mobile robot exhibits potential to be the driving system of robotic rovers.

The conditions leading to the beam cleanup effect induced by stimulated Brillouin scattering (SBS) have been debated by many researchers. In this paper, we firstly reveal that the key point of the beam cleanup induced by SBS is at the selective excitation of the fundamental mode of the Stokes beam, which is amplified by the counterpropagating high-order-mode pump beam along multimode fibers while preserving the fundamental mode and subsequently realizing the beam cleanup. This mechanism is theoretically modeled and experimentally demonstrated in this work.

In this paper, we report the simultaneous formation of both single-walled carbon nanotubes (SWCNTs) and multi-wall carbon nanotubes (MWCNTs) in a reactor by ultrasonic spray pyrolysis. MWCNTs were formed at the center of the tube since catalyst particles accumulated on the substrates at the center agglomerate into a larger size. However, SWCNTs were formed downstream of the tube on desired substrates. Light transmission of the fluorine-doped tin oxide (FTO) substrate is reduced after SWCNT formation but returns to its initial state after ozone treatment.

The spectroscopic properties of a series of chalcogenide apatite phosphors, pure and Ce-doped Sr10(PO4)6S, prepared by a high-temperature solid-state reaction technique, were investigated at different temperatures. The pure Sr10(PO4)6S powder shows a broad blue emission peaking at 472 nm (2.63 eV), which results from self-trapped exciton (STE) in the host lattice with the wavelength at 271 nm (4.57 eV). The decay time is about several microseconds. Activator ion Ce3+ shows general f–d transition luminescence with a decay time of more than 20 ns. The activation energy EA for thermal quenching of STE and Ce3+ luminescence was fitted.