Although many studies exist on mobile robot path planning, the disadvantages of complex algorithms and many path nodes in logistics warehouses and manufacturing workshops are obvious, mainly due to the inconsistency of map environment construction and pathfinding strategies. In this study, to improve the efficiency of mobile robot path planning, the Delaunay triangulation algorithm was used to process complex obstacles and generate Voronoi points as pathfinding priority nodes. The concept of the grid was used to extract obstacle edges to provide obstacle avoidance strategies for robot pathfinding. Subsequently, the search for priority and regular path nodes used the improved A-star (A*) algorithm. The dynamic fusion pathfinding algorithm (DFPA), based on Delaunay triangulation and improved A*, was designed, which realizes the path planning of mobile robots. MATLAB 2016a was used as the simulation software, to firstly verify the correctness of the DFPA, and then to compare the algorithm with other methods. The results show that under the experimental environment with the same start point, goal point, and number of obstacles, the map construction method and pathfinding strategy proposed in this paper reduce the planned path length of the mobile robot, the number of path nodes, and the cost of overall turn consumption, and increase the success rate of obtaining a path. The new dynamic map construction method and pathfinding strategy have important reference significance for processing chaotic maps, promoting intelligent navigation, and site selection planning.

Based on the background of a mine, this study aimed to improve underground wireless communication. The study selected Zigbee technology from many wireless technologies as the basis, expounded the technical advantages and disadvantages, and addressed its disadvantages. First, the modulation technology of Zigbee was improved. This article selects and describes O-QPSK technology from three modulation technologies, thereby addressing the synchronization difficulties caused by inherent technical reasons, and proposes a modulation method based on feedforward timing. Moreover, excellent performance was achieved in the follow-up simulation experiment. For networking problems, a series of mechanisms are proposed to address several problems in large-scale networking: node offline, energy waste, signal delay, etc. This article proposes five main mechanisms and an improved protocol from two significant perspectives. The problem of node disconnection is divided into two parts. Considering the different status of edge nodes and important nodes in the network, three mechanisms are proposed for edge nodes for disconnection detection and self-repair, and two mechanisms are proposed for essential nodes. This can compensate for the loss caused by the disconnection of essential nodes at a specific time. For network energy waste, an Improved-LEACH protocol is proposed to alleviate the signal delay problem. The performance of the five mechanisms and one protocol was verified in a simulation test, and the performance was reasonable and in line with expectations.

The poor loading performance of shearer drums restricts the development and production efficiency of coal in thin coal seams. Changing operation and structural parameters can improve the drum’s loading performance to some extent, but the effect is not obvious. A two-segment differential rotational speed drum (TDRSD) was proposed after analyzing the drum’s influence mechanism on coal particles. To further reveal the drum’s coal loading principle, the velocity, particles distribution, and loading rate were analyzed. The effect of the matching relationship of the rotational speed and helix angle between the front and rear drum are also discussed. The results show that a lower front drum rotational speed had a positive impact on improving the loading performance, and the loading rate first increases and then decreases with the increase in rear drum rotational speed. The optimal loading performance was obtained in the range 60–67.5 rpm. The front drum’s helix angle had no evident effect on loading performance, and the loading rate increase with the increase in the rear drum’s helix angle. The results provide a reference and guidance for operation parameters selection, structure design, and drum optimization.

To solve the problem of severe wear and low rock-breaking efficiency of a conical pick during rock cutting, a method of rock-breaking using a sawblade and conical pick is proposed, which can improve the rock-breaking ability and efficiency. Test benches for the sawblade rock cutting and conical-pick breaking were established to verify the numerical simulation model and improve the numerical simulation accuracy. The numerical simulation model of sawblade and conical-pick rock-cutting was used to investigate the effect of the cutting parameters on cutting performance. Based on the numerical simulation results of rock-breaking, a prediction model of the cutting force and specific cutting energy consumption for combined rock-breaking with a sawblade and conical pick was developed. This provides a comparative analysis basis for the combined rock-breaking capacity of sawblades and conical picks as well as traditional conical-pick rock-breaking. The results indicate that the cutting force, specific cutting energy consumption, and rock-breaking efficiency of combined rock-breaking with a sawblade and conical pick are better than those of the traditional conical pick. The research results provide a theoretical foundation for applying a combined rock-breaking method to sawblades and conical picks in engineering practice.

The volume detection of medical mice feed is crucial to understand the food intake requirements of mice at different growth stages and to grasp their growth, development, and health status. Aiming at the problem of volume calculation in the way of feed bulk in mice, a method for detecting the bulk volume of feed in mice based on binocular stereo vision was proposed. Firstly, the three-dimensional point coordinates of the feed's surface were calculated using the binocular stereo vision three-dimensional reconstruction technology. The coordinates of these dense points formed a point cloud, and then the projection method was used to calculate the volume of the point cloud; and finally, the volume of the mice feed was obtained. We use the stereo matching data set provided by the Middlebury evaluation platform to conduct experimental verification. The results show that our method effectively improves the matching degree of stereo matching and makes the three-dimensional point coordinates of the obtained feed's surface more accurate. The point cloud is then denoised and Delaunay triangulated, and the volume of the tetrahedron obtained after the triangulation is calculated and summed to obtain the total volume. We used different sizes of wood instead of feed for multiple volume calculations, and the average error between the calculated volume and the real volume was 7.12%. The experimental results show that the volume of the remaining feed of mice can be calculated by binocular stereo vision.

The rock cutting process with a circular sawblade and the rock breaking mechanism of rock are studied with a numerical simulation method in this paper. The influence of cutting parameters of the circular sawblade on cutting force, rock damage, and specific cutting energy in the process of circular sawblade cutting rock is researched. The cutting force increases with the feed speed and an increase in cutting depth and decline in rotation speed. Cutting rock with double circular sawblades can reduce cutting force. However, the specific cutting energy declines with the increase in cutting depth and the decline in the distance between the double circular sawblades. Cutting parameters have a great influence on the damage range of rock. The research results can be applied to rock processing with a circular sawblade.