To visualize the region of nuclear reactions of DD-fusion, the method of registration of protons with energy Ep = 3.02 MeV, formed in the second neutron-free channel, which has the same probability as the reaction in the neutron channel, was used. The results of recordings on the CR-39 track detector of the plasma cumulation region using two different coding diaphragms and the results of estimating the number of reactions in targets with an inverted corona using this method are presented.

Assessment of the accuracy of neural network manipulator control is considered. The accuracy is assessed by comparing the required clamp coordinates with the actual experimental coordinates for a DOBOT Magician robot manipulator. The proposed approach permits the formation of a complete control space with the required accuracy over the entire working region.

The arrangement and results of full-power experiments on the Iskra-5 laser facility (the laser energy is 150 J, the pulse length is 0.3 ns, and the laser-radiation intensity on the target is 1.6 × 1015 W/cm2) on focusing of hard X rays from a laser-plasma source with a Ga target using an ellipsoid with a HOPG crystal are described. The design of an ellipsoid focus pointer is described that made it possible to create an X-ray source at the focus of the ellipsoid with an accuracy of no worse than 100 μm. Focusing X-ray radiation into a 1-mm-diameter spot in full-power experiments was achieved at a distance of 250 mm. An eighty-fold increase in the X-ray flux density with a photon energy of 9.5 keV was attained.

The paper reviews the goal of controlling mobile robot movement along the planned path. It proposes an adaptive robot movement control algorithm, allowing to increase the precision of holding the robot within the prescribed path under the conditions of unstable navigation field. The adaptation of the algorithm to jamming environment is in redistributing weights of the weighted sum of estimates given by the ultrasound navigation system (USNS) and wheel pulse transducers (WPT). When precision of the USNS reduces affect of the WPT on the final estimate increases while affect of the USNS decreases. Such a redistribution is carried out when the system is operating due to changing elements of a measurement noise matrix in Kalman filter [1] with use of which a mobile robot heading angle is estimated. Corresponding elements of the measurement noise matrix increase along with increase of deviation of the mobile robot trajectory from a straight line. The extent of deviation calculated as the standard error of a regression is defined by means of the statistical analyses involving the last n measurements contained in buffer store of the USNS. The obtained results demonstrate significant benefit of the developed mobile robot heading estimation algorithm in comparison with the conventional filtering algorithm basing on using the classical Kalman filter with the measurement noise matrix whose elements are fixed.

An Erratum to this paper has been published: https://doi.org/10.1134/S0020441221060221

Algorithms for the organization of standalone operation of a robotic manipulator have been considered in this Article. The controls on the control panel of a man-made equipment piece have been the manipulated object. A robotic manipulator fitted with a control system, and a machine vision system, have been the subsystems under study. The robotic manipulator interacts with the objects to switch on and off a toggle switch, turn a rotary switch, press on a pushbutton, etc. Manipulating the objects in question involves assessing of their positions and orientations, which is achieved through the machine vision system. Coordinated operation of the subsystems is required to plan and to implement control of the manipulator, while taking into account positions of the objects relative to each other. A configuration of interactions between the manipulator and the control panel, a method for organizing coordinated functioning of the machine vision system when manipulating controls, which includes assessing positions of the object of interest relative to the robotic manipulator, and an algorithm for planning control based on artificial neural network technology have been presented in this Article.

This study considers the operation of an onboard navigation system, which determines the robot position in the environment. Navigation system (NS) errors arising (accumulated) in the process of operation from errors of accelerometers and angular velocity sensors shall be compensated by certain correction allowing to refine the robot coordinates. Various approaches are used to correct NS, in particular, visual navigation methods implemented in onboard computer vision systems. Most of the approaches use neural networks based on a computer vision system, which functions under the conditions of direct visibility of reference points. The disadvantages of methods with special markers include the need to install them in different locations of the room (on the walls, floor), which requires additional time and resources to organize the required information field. Furthermore, such methods are ineffective in a dynamically changing environment, in particular, in crowded rooms, where moving people or transport robots can obstruct reference points and disrupt NS operation. The approach proposed by the authors considers a scheme for integrating navigation data coming from the inertial measurement unit (IMU), encoder and computer vision system, and is based on the extended Kalman filter (EKF). Coordinate correction is carried out by a computer vision system, which matches the current images of the ceiling sections obtained by the robot to a previously prepared image of the entire ceiling. Matching is implemented by an extreme correlation algorithm for image matching. The proposed system allows solving robot's navigation tasks in a changing dynamic environment, in particular, with people moving around the robot. Experimental studies of the correlation algorithm for estimating coordinates have shown the centimeter accuracy of the visual coordinate estimation algorithm. Modeling the coordinate estimation process using the Kalman filter confirms the system's effectiveness, including cases of failure of one or more navigation devices.

The possibility of observing the stimulated de-excitation of nuclear isomers (SDENI) in plasma (plasma lifetime ∼1.5 ps, temperature of electrons ∼ 10 keV) formed by the impact of a high-power laser pulse (∼10 18 W cm −2 ) on a target is studied experimentally. Preliminary experiments are carried out with the 110 m Ag ( T 1/2 = 250 days) and 186 m Re ( T 1/2 = 2 × 10 5 years) isomers. A weak SDENI effect is observed only for the 110 m Ag isomer on a platinum backing.

The results of the development of an activation technique for measuring the DD-neutron yield based on the 115In(n, n′)115mIn reaction and its application in experiments on the inertial thermonuclear synthesis at the Iskra-5 laser facility are presented. The relative error of measurements at an integral yield of pulsed neutron radiation of approximately 108 neutrons was 35%. The experimental results demonstrated the applicability of this activation technique at existing and higher-power laser facilities.

We report on the results of experiments performed on the Iskra-5 laser facility for studying the effect of the polydeuteroethylene (CD 2 ) n working layer thickness on the operation parameter of an inverted-corona target. In all experiments of this series, the neutron yield at a level of 10 7 –3 × 10 8 DD neutrons per shot was detected for the total laser radiation energy supplied to the target by 12 second-harmonic beams in the range of 1.6–2.2 kJ. Using the neutron time-of-flight technique, we have detected an increase in the ion temperature from approximately 6.4 to 14 keV upon a decrease in the (CD 2 ) n layer thickness from 1 to 0.1 μm.

We present the results of preliminary experiments at laser facilities in which the processes of the undeniable destruction of stony asteroids (chondrites) in space by nuclear explosions on the asteroid surface are simulated based on the principle of physical similarity. We present the results of comparative gasdynamic computations of a model nuclear explosion on the surface of a large asteroid and computations of the impact of a laser pulse on a miniature asteroid simulator confirming the similarity of the key processes in the fullscale and model cases. The technology of fabricating miniature mockups with mechanical properties close to those of stony asteroids is described. For mini-mockups 4–10 mm in size differing by the shape and impact conditions, we have made an experimental estimate of the energy threshold for the undeniable destruction of a mockup and investigated the parameters of its fragmentation at a laser energy up to 500 J. The results obtained confirm the possibility of an experimental determination of the criteria for the destruction of asteroids of various types by a nuclear explosion in laser experiments. We show that the undeniable destruction of a large asteroid is possible at attainable nuclear explosion energies on its surface.

The hydrodynamics of the flow formation due to the interaction of a shock wave with two-dimensional density perturbations is experimentally investigated on the Iskra-5 laser facility. Shadow images of a jet arising as a result of the impact of a shock wave (formed by a soft X-ray pulse from a target-illuminator) on a flat aluminium target with a blind cylindrical cavity are recorded in experiments with point-like X-ray backlighting having a photon energy of ~4.5 keV. The sizes and mass of the jet ejected from the aluminium cavity by this shock wave are estimated. The experimental data are compared with the results of numerical simulation of the jet formation and dynamics according to the two-dimensional MID-ND2D code.

Pilot scheme for the study of plasma under extreme condition is implemented using a compound 3D X-ray lens. Hard X-ray image of laser plasma produced by irradiating of copper foil by intense laser pulse was recorded using this lens.