Development of the method of laser Doppler anemometry for diagnostics of turbulent flows at high speed

The aim of the work was to develop a laser Doppler anemometry method for high-speed turbulent aerodynamic flow diagnostic. As a result, this allowed us to measure two projections of the velocity vector in the range of 0.1 - 400 m/s with a relative error not exceeding 0.5%. The measurement area was 0.1x0.1x0.5mm. The positioning device moved the measuring unit in the area of 250 x 250 x 250 mm with an accuracy of 0.1 mm. This method also provides the ability to measure local flow rate fluctuations.

Influence of mechanical deflector assisted electroless nickel deposits for wear resistance

This investigation reports the effect of mechanical deflector during coating on the mechanical properties of the Electroless Ni-P deposits. Micro hardness of the electroless Ni-P deposits was measured using shimadzu micro hardness measuring unit employing a diamond indenter and pin-on-disc wear tester was used to measure the wear resistance of the deposits. The characteristics of deposits produced in presence of mechanical deflector are found to be superior from those produced using conventional deposition techniques. Enhancement in properties are correlated with modified crystallinity and the conversion of Ni-P in to possible phosphides in the presence of mechanical deflector. It has been noticed that the coating efficiency has 30% hike with mechanical deflector. Annealing at 350ºC has reached the maximum hardness of 950 Hv and subsequent increase in wear resistance.

Developing the laser doppler anemometry method for the diagnostics of kinematic parameters of a turbulent flow in the near wall region

The aim of the work is to develop a laser Doppler anemometry method for diagnosing turbulent aerodynamic flows in the near wall region. This will enable measuring two projections of the velocity vector in the range of 0.001 … 400 m/s with a relative error not exceeding 0.1%. The measurement area is 0.1×0.1x0.5mm. The positioning device allows moving the measuring unit in the area of 250×250x250 mm with an accuracy of 0.1 mm. This method also provides the ability to measure local flow rate fluctuations.

Investigation of the thermophysical characteristics of triticale grain of the Gorka variety by the method of non-stationary thermal re-gime

In solving the problem of vegetable protein deficiency, triticale grain is of great interest – a unique hybrid that com-bines the best hereditary qualities of wheat and rye. The protein content of triticale is 1.0 – 1.5% higher than that of wheat and 3–4% higher than that of rye. Obtained a new variety of grain triticale – "Slide". Products prepared from this grain crop have a high nutritional value, since the protein that is part of triticale is characterized by an increased content of essential amino acids, and is not inferior to wheat grain in terms of the content of macro – and micro-elements. It contains a lot of copper, phosphorus, potassium, magnesium, calcium, sodium, zinc, manganese and iron, as well as vitamins В9, В5, В1, PP and E. Information about thermal characteristics as functions of tempera-ture plays a key role in engineering calculations and mathematical modeling of the processes of drying and heat treatment of triticale grain. The method of nonstationary thermal regime, based on the solution of the problem of thermal conductivity over two temperature-time points, developed by B.C. Wolkenstein, was used to determine the thermophysical characteristics. The determination of the thermophysical characteristics of the grain was carried out on the Kossfield RT 1394 N measuring unit (National Instruments). Revealed the character of the dependence of diffusivity, thermal conductivity and specific heat capacity on temperature. Equations describing the thermophysi-cal characteristics of grain at a humidity of 13.57 and 21.83% in the temperature range of 20–100 оС are obtained

Design, Modeling and Simulation of a Liquid Jet Gyroscope Based on Electrochemical Transducers

We propose a novel liquid jet gyroscope based on electrochemical transducers, which uses electrolyte as the jet medium, and two electrochemical transducers placed symmetrically as the velocity measuring unit. The gyroscope includes a fluid pump to generate a jet flow, which flows into the jet chamber. Then, it is diverged into the shunt channels, pumped into reflux channels and merged by a fluid pump. The velocities of shunt flows are measured by two electrochemical transducers. The feasibility of the method was demonstrated in theory, and a 2D finite element model was built to simulate the dynamics of the liquid jet gyroscope. Simulation results confirm the effectiveness of the gyroscope, which has higher sensitivity in the near DC frequency band.

Analysis and Design of a Minimalist Step Climbing Robot

In this article, a novel yet simple step climbing robot is proposed and is comprised of two front wheels, a rear-wheel and an actuator to vary the center distance between the front and rear wheels. When a robot climbs a stair, the huge variance in the inclination angle of the robot may result in its toppling. Hence, a mechanism is proposed to compensate for the change in inclination angle. An inertial measuring unit (IMU) is used to sense the inclination angle of the robot which is then fed to a microcontroller in order to actuate the connecting link, thereby reducing the variation of the inclination angle. During ascending simulations on dynamic model based on the Newton–Euler formulation, the required torque on rear wheel is reduced by 26.3% as compared to uncontrolled simulations. Moreover, the normal reaction on rear wheel during descending simulation has increased by 170.9% by controlling the inclination angle, which reduced the probability of toppling of the proposed robot. Multiple experiments on the prototype with a controlled condition show that the variation in inclination angle is reduced by 77.8% during ascending, whereas it is reduced by 92.8% during descending resulting in successful operation on the stairs as compared to uncontrolled cases.

INCREASING OF AIMING AND SEARCH SYSTEM OF LAND UNMANNED COMPLEX DURABILITY

Proposals on composition of the aiming and search system of land unmanned complex are offered. The work aims to improve one of the most important technical characteristics of land unmanned complex - survivability. Proposals are given for improving the layout of aiming and search system of land unmanned complex. Existing composition schemes have a low firing life because of the devices included in its structure have are installed into general body. Sniper impact in body makes ineffective all aiming and search system. Authors proposes to install the devices into two bodies along weapon sides. TV-sight should be installed into the first body and thermal-vision sight should be installed into the second body. Then if sniper impact is affecting one body, then the devices of the second body are able to execute a battle task with some limitations thanks to efficient sight. The issues of controlling the stability of the aiming line of the aiming and search system at the stage of bench tests using a collimation-measuring unit are considered in detail. A technique for adjusting both television and thermal imaging sights is proposed. In addition to increasing the survivability of the entire unmanned complex, the proposed technical solution has a number of other advantages. First, the "cold" zeroing of the combat module is greatly simplified. Instead of a system of two penta mirrors, a BS-0 ° rhombus prism can be used for this. Secondly, the proposed layout potentially simplifies the further modernization of aiming and search system, which would require the inclusion of additional units. For example, to expand the functionality of the complex by analyzing the polarization of radiation from objects and backgrounds, an additional volume is provided to accommodate polarimetric attachments. Thirdly, an even greater increase in the survivability of the complex can be achieved by increasing the secrecy of the combat mission. Usage of the base distance between the entrance pupils of the sights makes it possible to passively measure the range to the target using the internal base rangefinder instead of the laser rangefinder.