A novel mechanical design of the broken rope protection device is proposed to enhance the safety performances of the overhead manned equipment. According to the operating characteristics and functional requirements of the overhead manned equipment, a three-dimensional mechanical model of the broken rope protection device was redesigned. Based on the known parameters of the mechanical model, the stress and strength of the main components are readjusted using the statics characteristics of finite element analysis. To ensure the reliability of the control system of the broken rope protection device, the process of people's falling, the response performance of the tension sensor, and the signal extraction of the broken rope are analyzed under different loading and unloading speeds. The working principle of the broken rope protection device is expounded in detail. The experimental results showed that better effect is obtained by the new broken rope protection device, which is characterized by good durability, low investment, and high reliability.

In this study, according to the experimental results related to the dissimilar laser welding of brass-stainless steel 308, a performance approximation method called artificial neural network (ANN) was used. Welding speed, focal length, peak power, pulse width, and frequency were taken as input parameters, and temperature and melting ratio were considered as target characteristics. The ANN results were compared with the experimental results and the error percentage between them was obtained. Maximum relative errors were 9.63%, 10.55%, and 6.13% for brass alloy temperature, stainless steel, and melt ratio, respectively. Based on this comparison, the percentage of error between the experimental data and the ANN was at a reasonable level; so, this numerical method could be used with low time and cost. Also, by considering seven and five neurons in the hidden layer, the lowest mean squared error was obtained for temperature and melting ratio, respectively.

Our aim was to study the influence of the surface treatment process on the mechanical properties of an adhesive. This study takes aluminum alloy 6061 as the substrate; carries out grinding, sandblasting, plasma, grinding + plasma, and sandblasting + plasma surface treatment processes; and chooses the ISR 7008 adhesive to make aluminum alloy butt joints, and the joints Connectors are in −40 °C, −20 °C, 0 °C, 40 °C, 60 °C, and 80 °C environments, respectively (1–3 days of a constant-temperature test). The results show that the plasma surface treatment process helps to improve the activity and hydrophilicity of the bonding surface; the plasma surface treatment process helps to improve the adhesive strength of the joints under the environment of −40 °C and 80 °C; and under the environment of −20–60 °C, the sandblasting + plasma surface treatment process helps to improve the adhesive strength of the joints. By analyzing the infrared spectra of the ISR 7008 adhesive, it was found that the contents of γN−H, νC−C, νC−N, and νC−O were higher in the interval from 25 °C to 80 °C than those in the interval from −40 °C to 0 °C, which resulted in the decrease in adhesive properties.

In this paper, a heat-flow coupling model of laser welding at preheating temperature was established by the FLUENT 19.0 software. The fluctuation of the keyhole wall and melt flow behavior in the molten pool under different preheating temperatures were analyzed, and the correlation between keyhole wall fluctuation and molten pool flow with spatters and bubbles was obtained. The results indicate that when the outer wall in the middle of the rear keyhole wall is convex, the inner wall is concave, which causes spatter or the bottom of the keyhole to collapse. When the metal layer in the middle of the rear keyhole wall turns into obliquely upward flow, welding spatter is generated. In contrast, the metal layer in the middle of the rear keyhole wall changes to flow into the keyhole, and the bottom of the keyhole collapses. When the preheating temperature is 300 K (ambient temperature), 400 K, and 500 K, the inner wall in the middle of the rear keyhole wall is concave. With the increase in the preheating temperature, the area of the concave gradually increases, and the size of the liquid column behind the keyhole opening gradually decreases. When the preheating temperature is 300 K, there are more spatters above the molten pool. In comparison, when the preheating temperature is 400 K or 500 K, there are less spatters, and the bottom of the keyhole collapses.