To repair leaking pipelines for oil, natural gas and other dangerous media, a kind of pipeline sealing robot is proposed. The device is mainly divided into a robot drive unit, connection unit, and blocking unit. The robot drive unit is used to pull the blocking unit, allowing it to move in the pipeline. The connection unit is used to connect the robot drive unit and the blocking unit. The blocking unit is used to complete the repair at the leakage point. When the robot operates, the drive unit drags the blocking device to the pipeline leakage location, and the front camera can detect the size and shape of the leakage hole. The sealing unit is located at the leakage point, an airbag is inflated, and the adhesive in it is used to seal and repair the leak. Two performance indices (climbing performance and curve passing performance) are evaluated when the robot drive unit is walking. A 3D model of the robot is established, and the performance index of the robot is simulated and analyzed using virtual prototype technology. An experimental platform is built for verification. The conclusions are as follows: (1) A spring with a 13 N/mm rigidity yielded the best performance, and the robot could crawl up a 37° slope. (2) When the deflection angle of the driving wheel was set to 30°, the robot could smoothly pass a bend with a radius of curvature of 500 mm. Thus, the robot performance met the design requirements

This study presents a spiral pipeline robot designed for detecting and preventing oil and gas pipeline leakages. A comprehensive analysis of factors such as spiral angle, normal force, pipe material, and operating attitude is conducted based on the robot’s mechanical model in a straight pipe. This in-depth investigation determines the optimal spiral angle, normal force, pipeline material, and operating attitude to enhance the robot’s motion stability and traction performance. Using virtual prototype technology, the robot’s traction performance is simulated under various working conditions, normal forces, and attitude angles within the pipeline. An experimental platform is established to verify the impact of deflection angle, normal force, and pipeline material on traction performance. The experimental results and simulation analysis mutually validate each other, providing a reliable reference for robot design and optimization. The spiral pipeline robot and its motion strategy proposed in this study possess both theoretical value and practical application prospects in the field of oil and gas pipeline inspection and maintenance.

In recent years, with the continuous development of new energy, how to efficiently use wind energy has received more and more market attention. Due to cost advantages, the development of small wind turbines is accelerating. Among them, the design and research of the airfoil design and research of the lift vertical axis wind turbine has matured, but because of the aerodynamic characteristics of the lift airfoil structure, it is impossible to start itself at low wind speed, resulting in the waste of low wind speed energy. Although the drag wind turbine has good self-starting performance, the wind energy utilization efficiency in the high-speed state is inefficient. Each has its own unique shortcomings, which directly affects the marketization of small wind turbines. In order to solve these problems, this paper presents a drag-lift hybrid type wind turbine structure based on an NACA0018 symmetrical airfoil, which can adaptively change the blade shape. This design can keep the blade in the drag shape under static and low speed conditions, and adaptively change the lift shape with the increase of speed. In addition, through the research method of CFD numerical simulation combined with physical experiments, the proposed wind turbine design is studied and analyzed from multiple angles. At the same time, the “6DOF + dynamic grid” setting is used to study the influence of the opening angle factor of the drag-lift hybrid blade on the self-starting performance, and the study shows that the design of the drag-lift hybrid blade proposed in this paper has a higher self-starting torque and lower starting wind speed than the traditional lifting blade, and it is observed that the drag-lift hybrid blade has the best self-starting performance when the opening angle of the blade is 80°. At the same time, the problem of switching the blade morphology of the drag-lift hybrid blade is also analyzed, along with how to use the spring to control all this adaptively. In order to better analyze the advantages of the drag-lift hybrid design proposed in this paper, a wind tunnel test was also carried out using the physical model, and the relationship between the leaf tip speed ratio and the wind energy utilization rate was obtained, which intuitively showed the improvement of the wind energy utilization rate of the drag-lift hybrid design compared with the traditional lift blade.

With the passage of time during pipeline operation, a substantial number of impurities accumulate and adhere to the inner wall of the pipeline. This deposition hinders the pipeline’s ability to function correctly, thereby posing significant hidden risks to people’s lives and the safety of their property. This article focuses on employing pipeline robots for internal cleaning. It examines the jet cleaning process of the spiral-driven pipeline inspection and cleaning robot, aiming to determine the optimal motion state and cleaning parameters for the device within the pipeline. The findings are verified and analyzed through experiments. It was observed that the cleaning effect is enhanced, with a target surface distance of approximately 12- to 13-times the diameter of the nozzle outlet (around 25 mm). In addition, an incident angle of 15° yields favorable cleaning results, with a maximum shear force exerted on the target surface of approximately 0.11 MPa. Ensuring that the pipelines operate reasonably and stably, thus guaranteeing their safe functioning and preventing significant economic and environmental damage, holds immense value.

This paper investigates the screening characteristics of the multi-layer vibrating screens. A portable linear screen with a three-layer screen mesh and the vibrating screening experimental platform were designed and simulated. Based on the discrete element method (DEM), the influences of the motor excitation frequency, the pulverized coal mass flow rate, and the shape of the particles on the screening accuracy of each layer of the screen and the total energy contained in the particles were analysed. The simulation analysis found that, during the vibration screening process, with the increase of the frequency of motor excitation, the screening accuracy of each screen layers increased first and then decreased. The ratio of the sieving accuracy of the first screen and the third screen is reduced first and then increased. The energy contained in the particles gradually increases. With the increased pulverized coal mass flow rate, the screening accuracy of each layer gradually decreased, while the ratio of the screening accuracy of the first layer to that of the third layer gradually increased. The energy contained in the particles gradually decreases. Similarly, the increased percentage of non-spherical particles generated slightly decreased screening accuracy and an increased ratio of the screening accuracy of the first and third screens. The particles also contain much less energy than spherical particles do. A simulation was carried out on the vibrating screening experimental platform with screening materials such as soybeans and red beans. The experimental results matched the discrete element simulation. The screening accuracy was proved to be higher when the excitation frequency lay in 18 Hz to 20 Hz, and the particles mass flow rate stayed below 0.4 kg/s. This study demonstrated that changing the shape of particles is a practical way of managing real screening work. It also provided a theoretical basis and reference for the design and applications of multi-layer vibrating screens.

In this paper, a compliant control scheme based on the optimization of the contact force of the robot leg is proposed to improve the stability of the whole moving process of the robot. Firstly, according to the motion state of the robot, the change of its center of gravity is analyzed, then the stable gait of the robot is determined by the stability margin, and the smooth control of the robot’s foot trajectory is realized. Finally, the compliant control model of the robot leg is established. In the process of moving, the contact force between the legs and the ground is optimized in real-time, so that the composite robot can walk steadily on uneven terrain. The 3-D model of the scorpion composite robot was built with ADAMS software, and dynamics simulation was carried out according to the compliant control scheme. This paper takes the robot’s walking speed and torso angle as performance evaluation indexes and verifies the effectiveness of the compliant control scheme. The cooperative motion stability test is carried out on the actual uneven terrain. The test results show that the robot’s pitch angle and roll angle are between ±0.5°, which meets the motion stability requirements of the robot and verifies the correctness of the compliant control scheme and control model proposed in this paper.