RUDN Journal of Engineering Research

Space robotics is rapidly becoming essential as satellites and orbital debris continue to increase, creating demand for reliable capture and servicing technologies. A central challenge lies in minimizing the impact forces generated during contact, which can threaten both the robot and the target. This paper addresses the problem by introducing a configuration optimization approach that leverages the concept of integrated effective mass (IEM) to reduce capture contact forces. The contribution of this study is twofold: it demonstrates how IEM serves as a practical performance metric for predicting capture safety, and it validates configuration optimization as an effective strategy for mitigating impact forces in free-floating space robots. The methodology applied a Hunt - Crossley contact model with hysteresis damping to simulate robot-target interactions under various manipulator configurations. A 7-DOF free-floating robot was modeled, and IEM was computed through Jacobian-based dynamic analysis. The coefficient of restitution was also tuned to balance rebound and capture stability. Results reveal a strong nonlinear relationship between IEM and contact force. Configurations with low IEM generated substantially lower forces: for example, an IEM of 0.0413 kg produced only 442 N, while an IEM of 1.7199 kg resulted in forces exceeding 4142 N. By tuning the restitution coefficient to approximately 0.8, rebound effects were minimized without compromising stability. The simulations confirmed that configuration optimization can reduce capture forces by nearly an order of magnitude while avoiding singularities. In conclusion, this work shows that planning manipulator configurations based on IEM analysis is not merely theoretical but a practical tool for safer, more reliable on-orbit servicing and debris removal. These findings reinforce configuration optimization as a cornerstone for the next generation of space robotic operations.

The operation of spacecraft with nuclear power plants operating under the influence of their own external atmosphere is associated with the effect of radiation transfer from the near-reactor zone to the area near the instrument compartment. This phenomenon is called “induced radiation”. Induced radiation has a negative effect on the equipment in the area near the instrument compartment. To protect against induced radiation, this article suggests, together with traditional protection methods, using special devices that provide additional radiation protection for spacecraft with nuclear power plants. These include: a positively charged separation screen; gas nozzles for purging the outboard space; electronic plasma neutralizers with thermionic cathodes. The combined use of traditional methods and additional protection devices to reduce the negative impact of a nuclear reactor will significantly extend the service life of the spacecraft.

Ball radial bearings are often used as shaft supports. They are designed to withstand radial loads. However, they are also quite efficient under axial loads. To determine the degree of influence of axial loads on the performance of these bearings, the nature of the interaction of rolling elements with the rings of single-row ball radial bearings installed in a thrust manner under a combined load is considered. A method for determining the ultimate radial and axial loads for these bearings has been developed. Expressions have been obtained that relate the axial load to the unused radial load. Specific examples have shown that the greatest reaction of supports with single-row ball radial bearings under a combined load on the shaft, when the axial load is ultimate, can be twice as great as a similar reaction of supports under only a radial load of the same magnitude on the shaft. An excessively large error in determining the reactions of shaft supports significantly reduces the performance of the bearings selected for it, accelerating their failure. In addition, when a calculation scheme for a shaft supported by radial ball bearings is drawn up, the shaft is always represented as a beam on two hinged supports. One of the supports was a fixed hinge, and the other was a movable hinge. It has been established that under the action of a combined load, both supports operate as fixed hinges because both perceive an axial load. In this case, one part of the shaft between the supports was stretched, and the other was compressed. The boundary between the stretched and compressed zones was the point of application of the axial force.

The minimax formulation of the problem of linear stationary control based on incomplete data of multidimensional stationary in a broad sense random processes (vector useful signal) observed in an additive mixture with interference of the “white noise” type, when the spectral densities of disturbances in the measurement channel and in the measurement interference are completely unknown and belong to a certain set of non-negatively defined functions, is considered. Only the condition of linear regularity is imposed on the observed vector process. A guaranteeing estimate is considered, which means the best estimate of the parameters of a useful signal in the sense of a minimum standard error with the worst behavior of measurement errors and disturbances with spectral densities belonging to the set, with respect to which the optimal control is determined based on incomplete data. Regarding the spectral density of the useful signal, it is only known that it satisfies a given system of moment conditions and is concentrated on a given measurable subset of the frequency axis. It is shown that the factorization of the matrix spectral density makes it possible to obtain a solution to the problem of optimal minimax linear filtration and is necessary to solve the problem of linear optimal control based on incomplete data. The search for optimal control based on incomplete data from the emerging multidimensional antagonistic game is reduced to solving a specific system of relations. Matrix boundary value problem methods, Hilbert matrix transformations, and properties of matrix frequency characteristics are used in the solution. An illustrative example is presented.

The purpose of this study is to develop and describe software for the organization of labor protection during the construction of the Amur Gas Processing Plant (AGPP). The described methodology is based on risk assessment and selection of measures for managing the organization of construction and installation works. The professional risk management system was developed and put into practice in the 4th quarter of 2020. In 2022, based on the established database of identified hazards and their management measures, work was carried out to automate the process of hazard identification, as well as the formation of risk management maps and the familiarization of employees with the contents of these maps. The development and implementation of the proposed methodology has led to a significant reduction in the rates of health disorders of AGPZ employees both in terms of work-related diseases and injuries. The software developed as a result of the conducted research for professional risk assessment and management is recommended for practical use in the construction of new petrochemical and gas chemical plants.

This study investigates the evaluation of a new approach for the pipeline route design process using the synthesis of artificial intelligence algorithms and Earth remote sensing data. For the effective construction of gas pipelines, a thorough comprehensive analysis of various geological, environmental, economic, and infrastructural factors is necessary. Route design is based on the principle of building a trajectory with the lowest cost. For this purpose, a multifactorial analysis of the territory was conducted according to key parameters that affect the financial costs during construction. The following groups of features were identified: water barriers, geomorphological factors, existing transport routes, specially protected natural areas, and proximity to large settlements. The approach of multifactorial suitability analysis was studied and adapted, on the basis of which the cost map used in the search for the path of lowest cost was formed. The main result of this study is the obtained software solution, which provides optimization of weighting coefficients in the multifactorial analysis of territories for laying main gas pipelines based on a genetic algorithm. The advantages of the proposed approach are the automation of the process and consideration of the regional characteristics of the territories. As a practical application, trajectories have been developed to solve the problem of gasification in the Krasnoyarsk Territory of the Russian Federation.