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The article discusses the special configurations (singularities) of spatial l-coordinate mechanisms. At the beginning, the position is shown where all the l-coordinate axes intersect the OX axis. In this case, there is a twist, reciprocal to all unit screws of the axes of prismatic kinematic pairs, this reciprocal twist coincides with the OX axis. In addition, a twist-gradient was found, which brings the mechanism out of a special position (singularity). In this case, the centers of the spherical hinges of the base are located on the plane z = –1. The centers of the spherical hinges of the output link are located at different distances from the XOY plane. Then, all the centers of the spherical hinges of the output link are located on the plane z = 1. The twist-gradient changes in this case. When changing the positions of the planes on which the centers of the spherical hinges of the bases and the output link are located, the twist-gradient no longer changes.

This paper presents a mechanism with parallel structure that is classified to the class of l‑coordinate mechanisms. The section of the singularity zone (of the zone of singular positions) is determined for this mechanism. The section is constructed at a constant orientation of the output linkage.

The use of mechatronic rotary linear modules in manipulators of machine-tool equipment is considered. A solution to the inverse position problem is presented, and the kinematic capabilities of a device based on mechatronic rotary linear modules for machine-tool equipment are evaluated. Dynamic equations have been derived used to evaluate the dynamic characteristics and the precision of the finishing of complex surfaces by the example of the machining of a gas-turbine engine blade feather.

When performing certain technological operations, multi-coordinate industrial robots require simultaneous control of the movement of the executive body and the developed effort. When performing assembly operations (for example, a shaft with a bush), it is necessary to perform a free movement of the shaft along the bore of the bushing and to ensure minimum pressure on the bore walls. When performing operations to handle complex surfaces of parts, it is simultaneously required to move the tool over the surface at a specified speed and to perform a metered pressure on the surface. Since it is impossible to control the force and motion simultaneously at the same coordinate, it is necessary either to switch from one control method to another, or to control various actuators and different controllable coordinates of the actuator. In multi-coordinate robots, this task is complicated by the fact that to control the movement of one of the Cartesian coordinates of the executive body, and by another force, it is simultaneously necessary to control the interrelated generalized coordinates of the robot’s mechanism. In the work presented, the solution of the problem of control of a six-coordinate industrial robot is described, in which the separation of the degrees of mobility into power control and positional control of trajectory motion is carried out. In order to accomplish the task, additional variable parameters are introduced for the treatment of complex surfaces, which determine the position of the cutting edge on the cutting surface, which makes it possible to expand the service area of the robot during selection, for example, one of the coordinates for controlling the pressure force. This task is considered using the example of a six-coordinate industrial robot when performing a complex surface treatment operation, when it is required to program the tool at a specified speed along a path on the surface and at the same time carry out the controlled pressure of the tool on the surface.

The article deals with a complex application for the structural synthesis and parametric optimization of the design of transportation and technological systems and evaluation of innovative engineering solutions based on advanced morphological approach. The approach is based on the multicriterion principles, cluster analysis, and the theory of sets. The article provides examples of application of the proposed approach to the selection of the process of manufacturing of long hollow shafts of gas turbine engines from heat-resistant alloys and steels under isothermal conditions, determination of the optimal values of the resonant transducer for reducing longitudinal vibrations of a mechanical system, and synthesis of transportation systems. The application of the advanced morphological approach enables the refining and ordering of the structuring of the problems to be solved. The degree of the validity of the adopted solution is considerably increased by applying to every variant of the selected structure the method of parametric optimization of the LPS search implemented by a separate algorithm, which enables enhancement of the quality (technological level) of the technical systems under design.

Laser-shock-wave processing (LSWP) of materials is an innovative material processing technology in which considerable compressive residual stresses are generated in the surface region and contribute to improved strength and performance parameters. We analyze performance capabilities of lasers operating at higher frequencies and lower energy levels compared to lasers used with traditional LSWP technologies. Finite element modeling of compressive residual stresses at different stages of laser spot overlap for BT-6 titanium alloys is carried out. The results are compared with the known experimental data. It is shown that they are correlate well with each other.

Laser shock processing (LSP) is an innovative surface treatment technique. It can impart compressive residual stresses in material for improving the fatigue, corrosion, and wear resistance of metals. This technology has been used successfully for the treatment not only of traditional structural materials, but also for hard materials. FEM simulation is an effective method for the prediction of mechanical effects induced in material treated by laser shock processing. The FEM simulation of the single and multiple laser shock processing has been carried out to predict the residual stress field. The predicted residual stress field for single and multiple laser shock processing is well correlated with available experimental data. The simulation of multiple laser shocks has shown that compressive residual stresses and, thus, the strength properties of processed materials, can be extensively increased (up to 40%) with the increase of the laser shock number up to 5, and then they gradually reach a saturated state.

Problems of analysis and synthesis of a parallel structure mechanism without singularities are considered in this paper. The spatial l-coordinate parallel structure mechanism, consisting of a base and an output link, connected with each other by six SPS kinematic chain, each of them containing one driven prismatic (P) kinematic pair and two nondriven spherical (S) pairs, is synthesized. The grapho-analytical method was used as a method of analysis and synthesis.

In the production of radioiodine via charged particle activation of isotopically enriched TeO 2 and subsequent heating of the irradiated target, some TeO 2 is lost. Again, use of recovered TeO 2 for radioiodine production showed that impurities are present, which prevent complete volatilization of radioiodine from the heated target. An effective purification procedure for recovered TeO 2 has been developed, resulting in a yield of 95–97%. The procedure developed may also be used to purify Te metal.

The effects of tritium substitution in imipramine (IMI) and N-desmethylimipramine (DMI) on their liquid chromatography are described. Increased elution times for tritiated analogues of IMI and DMI were observed using isocratic reversed-phase HPLC techniques. It was shown that the retention of labelled molecules depends on number and position of the tritium atoms. An explanation of the observed phenomena is offered.

The possibility of chromatographic separation of different isotopic forms of tritiated nucleosides has been demonstrated. Using a reversed-phase column in 3–5% solutions of ethanol in water the labelled nucleosides eluted ahead of corresponding unlabelled analogs. Such isotope effects allow simultaneous fine purification of nucleosides and its fractionation according to molar specific activity value.