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In response to the explosion-proof index requirements of the observation window in the cockpit of a certain type of explosion-proof excavator, this study conducts analysis and research on the explosion-proof performance of explosion-proof materials through theoretical calculations, simulation analysis, real explosion tests, and other methods. We simulate the penetration process of shrapnel by using simulation calculation methods and verify the reliability of explosion-proof materials in actual explosion tests. The results show that the simulation analysis and actual explosion test conclusions can support the selection of explosion-proof materials and effectively solve the safety problems of personnel in the cab of a certain type of explosion-proof excavator.

The article presents the results of a comprehensive analysis and development of an electric power metering device on device for technological machines on the basis of a comprehensive heat and power survey. The result of the research showed that it is advisable to use electronic electric energy meters to account for electric energy on excavators and drilling rigs, which provide a smaller error compared to induction ones. To account for electrical energy on excavators and burst machines, it is advisable to use electronic meters of electrical energy, which provide a lower error in comparison with induction meters.

Aim: Globally, many bird species nest in tree cavities that are either excavated or formed through decay or damage processes. We assembled an overview of all tree-cavity nesters (excavators and non-excavators) in the world, analysed their geographic distribution and listed the conservation status of all species. Location: This is a global analysis of species from every continent except for Antarctica where the lack of trees precludes the occurrence of this group. Methods: We reviewed the online version of the Handbook of the Birds of the World Alive, http://www.hbw.com/, and primary literature for species known to nest in tree cavities, with tree cavities defined as holes that a bird can enter such that it is not visible from the outside. We classified species by nester type (excavator or non-excavator, and obligate or facultative where possible), conservation threat status and zoogeographic region, and tested for statistical differences in species distributions across realms using chi-square tests. Results: At least 1878 species (18.1% of all bird species in the world) nest in tree cavities, of which we considered 355 to be primary excavators, 126 facultative excavators and 1357 non-excavators (we were unable to classify nesting type for 40 species). At least 338 species use cavities created by woodpeckers (Picidae), excluding reuse by woodpeckers themselves. About 13% (249 species) of tree-cavity nesters experience major threats (i.e., status of vulnerable, endangered or critically endangered). The highest richness of tree-cavity nesters is found in the Neotropical (678 species) and Oriental (453) regions, and the highest proportion of threatened species in Australasia (17%). Main conclusion: Maintenance of a continual supply of cavities, a process in which woodpeckers and the processes of decay play critical roles, is a global conservation priority as tree cavities provide important nesting sites for many bird species.

Taking the forearm of the hydraulic excavator as the research object, the working condition of the forearm is analyzed, the mathematical model of the forearm component is established, and the boundary load of the forearm is calculated. Altair Inspire software is used to conduct a simulation analysis of the preliminary design of the forearm components. According to the simulation results, the structure of the forearm is topologically optimized, and the optimized structure is verified. The results show that under the premise of not affecting the mechanical properties, the optimized structure is reduced by 36.32%, the load capacity is increased, and the production cost is reduced.

The the mining enterprises of the Republic of Uzbekistan pay great attention to improving the quality of operation of the main excavation and loading equipment, including reliability and durability of components and assemblies. The deepening of quarries in the mining processes leads to an expansion of the requirements for the efficient operation of hydraulic excavators and the reliable use of their power during excavation work in extremely difficult conditions. Modern hydraulic excavators are expensive technological equipment due to the high precision of manufacturing parts and require high-quality technical culture during their maintenance during operation. The operation of the excavator depends on a complex hydraulic system, the degree of malfunction of which reaches high levels today and becomes one of the main problems. Therefore, issues related to reducing the cost of operation of hydraulic systems of quarry excavators, increasing their reliability, are relevant.

Balancing the excavator structure is a widely considered topic that directly relies on the operation, the wear of nodes connecting the upper and the lower structures of the excavator and especially on the stability of the excavator at the operational site. The present paper considers the balance of the excavator structures of the SRs 2000 excavator with idealization to some static positions and simplification of the interactions to static ones. This allows positional regard of the most used positions under operating conditions. This approach derives some dependences clarifying the static balancing of the super structure of the excavator to the undercarriage, taking into account the interactions of both the weight parameters, as of the structural units, as of the main external forces. There are derived dependences for determining the load of ballast weights during repair and modernization of excavator structures

The paper deals with the factors of the possible reasons for the deterioration of the functional characteristics of a career crawler excavator, identifying such factors as \"machine - career excavator\", \"personnel - excavator drivers\", \"materials\" and \"external environment\" as well as secondary causes, main aspects of these factors. The reasons for the failures of the career excavator stick in the conditions of the ore deposits of the Southern Urals are established. It is shown that the greatest number of failures is associated with excavator drivers' low qualifications and insufficient experience.

We present a terrain traversability mapping and navigation system (TNS) for autonomous excavator applications in an unstructured environment. We use an efficient approach to extract terrain features from RGB images and 3D point clouds and incorporate them into a global map for planning and navigation. Our system can adapt to changing environments and update the terrain information in real-time. Moreover, we present a novel dataset, the Complex Worksite Terrain dataset, which consists of RGB images from construction sites with seven categories based on navigability. Our novel algorithms improve the mapping accuracy over previous methods by 4.17–30.48% and reduce MSE on the traversability map by 13.8–71.4%. We have combined our mapping approach with planning and control modules in an autonomous excavator navigation system and observe 49.3% improvement in the overall success rate. Based on TNS, we demonstrate the first autonomous excavator that can navigate through unstructured environments consisting of deep pits, steep hills, rock piles, and other complex terrain features. In addition, we combine the proposed TNS with the autonomous excavation system (AES), and deploy the new pipeline, TNES, on a more complex construction site. With minimum human intervention, we demonstrate autonomous navigation capability with excavation tasks.

The energy-saving of hydraulic excavators is evaluated by two significant indicators: operating efficiency (digging weight per unit time) and fuel consumption (volume of fuel consumed per unit time). These two indicators are only the final test results and cannot quantitatively evaluate the whole operation process of the excavator. In this paper, a complete set of experimental protocols is designed to quantify the energy-saving of the excavator by collecting its attitude data, fuel consumption data, and digging weight data in real-time. By restoring the excavator’s three-dimensional posture through the multi-body dynamics model, the posture corresponding to the energy efficiency of the excavator can be grasped very intuitively, which provides a research direction for optimizing the energy efficiency of the excavator.

Due to the fact that intelligent algorithms such as Particle Swarm Optimization (PSO) and Differential Evolution (DE) are susceptible to local optima and the efficiency of solving an optimal solution is low when solving the optimal trajectory, this paper uses the Sequential Quadratic Programming (SQP) algorithm for the optimal trajectory planning of a hydraulic robotic excavator. To achieve high efficiency and stationarity during the operation of the hydraulic robotic excavator, the trade-off between the time and jerk is considered. Cubic splines were used to interpolate in joint space, and the optimal time-jerk trajectory was obtained using the SQP with joint angular velocity, angular acceleration, and jerk as constraints. The optimal angle curves of each joint were obtained, and the optimal time-jerk trajectory planning of the excavator was realized. Experimental results show that the SQP method under the same weight is more efficient in solving the optimal solution and the optimal excavating trajectory is smoother, and each joint can reach the target point with smaller angular velocity, and acceleration change, which avoids the impact of each joint during operation and conserves working time. Finally, the excavator autonomous operation becomes more stable and efficient.