Onboard Control System Research Articles

MATHEMATICAL MODEL OF THE ESTIMATION OF THE EFFICIENCY OF THE CONTROL OF RADIO ELECTRONIC COUNTERACTION OF THE AIRPORT STATION OF ACTIVE CONTEMPORARY INTERFERENCES IN THE CONDITIONS OF CREATING A POLARIZATION INTERFACE ON A FIXED PLANE OF IT

In the article, based on the analysis of the use of modern individual on-board electronics and electronic search and guidance systems, it is concluded that one of the promising directions for their further development is the search for methods of not only protection from the means of radio-electronic suppression, but also an active counteraction to these means, the so-called counter-radio electronic counteraction One of the most effective obstacles that can be created by radar detection systems by stations is the active barrier of individual enemy protection - this is a polarizing obstacle, so the issue of reducing the effectiveness of the polarizing effect on the system of automatic support for the direction of the on-board radar weapon control system is quite relevant today. In order to counteract the station's active interference in the conditions of its creation of a polarization obstacle, it is proposed to change the plane of polarization on the receiving side. As a result, a useful signal will be taken in polarization, which does not coincide with the polarization plane of the radiation signal. Failure to match polarization when receiving a reflected signal will not significantly affect the power of a useful signal. In order to implement the proposed method in the article, a mathematical model for evaluating the effectiveness of the counter-radio-electronic counteraction of the on-board station was proposed to obstruct the enemy's individual protection in the conditions of its creation of a polarization obstacle on a fixed plane of polarization, as well as features of the practical realization of such counteraction during air combat and restrictions on its creation. The mathematical model of the evaluation of the effectiveness of the counter-electronic counteraction to the aircraft station's active barriers in the conditions of its creation of a polarization obstacle on a fixed plane of polarization is developed, it will allow to formulate practical recommendations regarding the application of the developed method at different stages of air combat. KELP management in different ways, on the one hand, slightly reduces the effectiveness of the on-board management of weapons at different stages of flight, but on the other hand, the effectiveness of the airborne equipment of the airborne ejection of the enemy significantly decreases, which will increase the effectiveness of the use of weapons and the likelihood of damage to the enemy aircraft using the means of destruction, which today have a significant cost.

The hardware and software implementation of the adaptive platform for an onboard spacecraft control system

In this paper the authors discuss hardware and software implementation solutions for an adaptable platform used in onboard spacecraft electronic equipment complexes. The proposed solutions ensure the reduction of time required for designing and manufacturing the spacecraft, increase of the export potential of communication and other services by enabling the adaptation of the onboard equipment to new protocols and technologies in the fields of communication, data processing, and control in the process of the spacecraft’s operation in orbit and expanding its hardware and software unification.

Redchyts Evaluation of aerodynamic and thermal loads on the HYPERLOOP capsule fuselage in a partly evacuated tube

Aerodynamics occupies an important place in the design of high-speed ground transportation systems. When a vehicle is moving at a speed above 500 km/h under atmospheric pressure, the main energy is spent to overcome the aerodynamic drag. Creating a rarefied atmosphere inside a sealed pipe in order to significantly reduce energy loss is one of the key ideas of the HYPERLOOP project [1].The paper assesses the aerodynamic and thermal loads on the HYPERLOOP capsule fuselage in a partly evacuated tube based on the numerical solution of the Navier-Stokes equations of compressible flow closed by a differential turbulence model [2-4]. Numerical modeling was carried out with the help of the computational fluid dynamics software developed by the scientific researchers of the Institute of Transport Systems and Technologies of the National Academy of Sciences of Ukraine [5].It was shown that even under conditions of low air pressure in a partly evacuated tube the high-speed movement of the HYPERLOOP capsule will be accompanied by the formation of local supersonic zones, shock waves and non-stationary vortex systems. The structure of the flow essentially depends on geometry of the streamlined capsule and the speed of its movement.It was found that the flow structure and the values of aerodynamic dimensionless coefficients weakly depend on the pressure in the partly evacuated tube. Thus, the aerodynamic forces acting on the HYPERLOOP capsule at the same speeds are almost directly proportional to the pressure value in the tube.A certain problem in the design of the HYPERLOOP type high-speed vehicles will be the aerodynamic heating of the capsule fuselage. When the capsule moves at transonic speed the temperature of the outer surface of the capsule will be 60÷900 C. This heat load can have a negative impact on the performance of onboard power supply and control systems, as well as on the ensuring of the passengers’ comfort on the way.

The revised method for calculating of the optimal train control mode

Development of a method for calculating the optimal mode of conducting a train in terms of energy saving meet the safety requirements and schedules. The method of calculation must solve the assigned tasks without significant time spent on the calculation. To implement this method of calculation was used a simplified model of the train as a controlled system. The existing mathematical and algorithmic methods for solving isoperimetric problems of finding the optimal solution in the presence of restrictions on resources were the information base for methodology development. Scientific works of domestic and foreign scientists, professional periodicals, materials of scientific and practical conferences, methodical and normative materials, currently in force on Ukrainian Railways. The results of these studies were used to create simulators on the basis of computer technology for the training of locomotive drivers. The scientific novelty of the proposed calculation method consists in applying the simplified calculations of the status of the train as a controlled system, without the use of differential equations of motion that allows to significantly increase the speed of the calculations. This, in turn, will solve the problems of finding optimal control in real time, taking into account changing conditions during the movement of the train. The practical significance of the obtained results is the use of such a calculation method that does not require significant time for its implementation and can be used as a subsystem of the on-board train control system capable of per-forming calculations taking into account changes in the current train situation.

Pressure Drop of Particulate Filters and Correlation with the Deposited Soot for Heavy-Duty Engines

<div class="section abstract"><div class="htmlview paragraph">Particulate filters are a widely used emission control device on heavy-duty diesel engines. The accumulation of particulate matter, mostly consisting of soot, inside the filter results in increased filter pressure-drop (backpressure). This increased backpressure has been used by the on-board control systems as trigger for regeneration procedures, which aim to actively oxidize the accumulated soot. However, it is known that passive soot oxidation during normal operation affects the correlation between backpressure and the deposited soot mass in filter. Therefore, the backpressure alone cannot be a reliable trigger for regeneration. In this work we highlight operating conditions with very poor correlation between backpressure and accumulated soot mass in filter and evaluate the possible root causes.</div><div class="htmlview paragraph">Experiments with several heavy-duty diesel engines and particulate filters were conducted on engine test bench. These experiments involved prolonged operation under conditions emulating real-world operation. Under certain conditions, the backpressure of the filter did not correlate with the accumulated soot mass: although the soot mass increased monotonically, reaching the regeneration soot mass limit, the measured backpressure corresponded to the backpressure of an almost clean filter. The quality of correlation was found to depend on the operating conditions, PM/NOx engine out emissions as well as on the type of filter used.</div><div class="htmlview paragraph">To investigate these complex interactions, we used an extensive experimental protocol to calibrate a physico-chemically informed mathematical model of the soot oxidation and the soot properties in the filter. We employed this model to investigate the possible reasons for the apparent lack of correlation between backpressure and accumulated soot mass. The simulation study confirmed the experimental findings: even minor passive soot oxidation may destroy the correlation between soot loading and filter backpressure. Moreover, simulation revealed the relative contribution of the following factors on the filter backpressure: microscopically, changes in the properties of the deposited soot, due to oxidation and compaction; macroscopically, non-uniform soot distribution inside the filter channels, due to transient flow and passive soot oxidation. Finally, simulations showed that the ratio of incoming soot from the engine to oxidizing soot in filter has a major impact on the potential to re-establish a correlation between soot loading and backpressure.</div></div>

Modeling of algorithms of disaster tolerance of robot groups on hardware and software Elbrus

In operation of ground-based robotic systems for military purposes, due to target actions of an opposing party, numerous failures might occur that lead to a suddenly changed state of the system and, therefore, fall into the category of catastrophic failures. In this case, we face the question of providing the disaster tolerance as an ability of a group of robots to continue operations with partially lost efficiency. A significant but still unresolved issue regarding ground-based robot systems is their equipment with computing equipment developed on domestic microprocessors and software. The paper includes offered techniques and algorithms that serve as a basis for building of disaster-tolerant control systems of ground-based robot systems based on domestic computer systems and software. Authors have developed the algorithms to ensure tolerance of on-board control systems against catastrophic failures. Authors have received numerical results that show the increased operation time of groups of robots in case of catastrophic failures. The findings improve import substitution options in the field of robotics.

Development Principles for UAVs Onboard Control Systems of Various Reliability Classes

Development Principles for UAVs Onboard Control Systems of Various Reliability Classes

Аналіз можливостей існуючих систем оповіщення про ракетну атаку, які встановлені на літальних апаратах

The study of new systems of individual protection of aircraft from all types of guided missile weapons with infrared homing heads and radio-controlled missile weapons, which occupy a special role in the performance of tasks by flight crews in modern combat conditions, is gaining increasing relevance every day. This area has been the subject of scientific research institutions of the Ministry of Defense and state-owned enterprises of the military-industrial complex of Ukraine. The results of the analysis of the capabilities of existing missile attack warning systems, which are installed on aircraft developed in advanced countries of the world, enabled the author to come to the definition of the direction of research of promising systems for protecting aircraft against air defense systems. One of the promising such studies is the creation of an automated complex for the active protection of the aircraft, with the aim of increasing the efficiency of using the onboard aircraft weapon control systems. The article provides an analysis of existing warning systems for a rocket attack of the advanced countries of the world from air-to-air and air-to-surface missiles. Existing common missile warning systems of advanced countries from shut downing the air-to-air and air-to-surface missiles were studied in this article. According to the results of the analysis of technical and scientific literature carried out by the author, offered the perspective directions of developing an automated complex of active protection of aircraft of Ukrainian Air Force.

ОЦІНЮВАННЯ ГОТОВНОСТІ ІНФОРМАЦІЙНО-КЕРУЮЧОЇ СИСТЕМИ КОСМІЧНОГО АПАРАТУ З УСУНЕННЯМ ПРОГРАМНИХ ДЕФЕКТІВ ПІСЛЯ ПРОВЕДЕННЯ ОПЕРАТИВНОЇ ОНЛАЙН-ВЕРИФІКАЦІЇ

The paper deals the multi-fragmental model of the two-channel space on-board information and control system of piloted spaceship. The model describes process of on-line software verification considering subsequent elimination of detected software faults. To take into account the change of software failure rate, the apparatus of regular multi-fragmental Markov’s models is used. The algorithm of determining sets of state fragments, states, transitions is proposed. It is considered the most widespread architecture of the information-control system, which includes two redundant hardware channels. Each channel has the same software version. After a failure caused by software faults, the information and control system is restored by restarting. Particularity of the researched system is performing of on-line software verification during its operation. The state of verification is considered as down-state on availability assessing. After onset software faults, degradation of program functions does not occur. The system is recoveredafter the failed state and continues functioning. For the estimation of the availability function, the Markov’s model for different sets of input data is researched. For that Matlab programs were developed. To solve the system of differential equations, an embedded Matlab ode15s solver is used. It is revealed that with increasing probability of faults detection during on-linesoftware verification, the availability of the system will increase at the end of the time interval of the model study. In order to accelerate the transition of the availability to stationary state, it is necessary to carry out more frequent verification procedures and try to eliminate a greater number of software faults in one check. In the initial period of operation, the availability of systems with planned on-line verification is lower than that of systems without fixing software faults. According to the results of the simulation, conclusions about the influence of the time parameters of the verification on the fault elimination intensity and the minimum of availability functions are formulated.

On-board information and control systems that automate the movement of vehicles in a column using the example of heavy vehicles

The subject of this article is on-board information control systems that ensure the movement of heavy vehicles in a convoy with the driver only in the first car, as well as cruise control systems, including adaptive and intelligent ones. The purpose of the article is the formation of the specified on-board system of a heavy truck, which includes both a set of algorithms and key functions that implement movement in a column, and a list of used categories of sensors. All considered functions are arranged hierarchically at three levels: strategic, tactical and operational. The study collected both theoretical and practical information provided by automakers, revealing the essential content of onboard information systems and cruise control. The novelty of the study lies in the fact that the model of intellectual cruise control has been improved, providing movement of heavy vehicles in a convoy, if there is a driver only in the first car. The proposed model includes the hierarchical architecture of the on-board information management system, key algorithms and sensors for its implementation.

CHOOSING THE SYSTEM OF LOCOMOTIVE MAINTENANCE IN VIEW OF THE EFFECT OF DEPENDENT FAILURES

Purpose. Improving the efficiency of the use of locomotives by choosing a rational maintenance system that takes into account the assessment of the effect of dependent failures on the cost of their life cycle is the main purpose of this paper. Methodology. The relevance of introducing LCC (Life Cycle Cost) approaches in locomotive facilities is explained by the introduction of new locomotives with on-board control and diagnostic systems, as well as the development of the theory of traction rolling stock maintenance systems. The cost of a locomotive as a traction unit ceases to be the determining factor. This is because the locomotive maintenance and repair cost for the entire period of its operation is much higher than the initial cost of the locomotive. The paper analyses the existing approaches to managing the cost of the life cycle of locomotives at the stages of selecting, updating, upgrading and operating the traction rolling stock. The necessity of improving the methods for assessing the degree of influence of reliability indicators of locomotive assemblies on the choice of the maintenance system and the cost of the locomotive life cycle is substantiated. Findings. It is proposed to use the concept of «the effect of dependent failures» when calculating the cost of locomotive renewal after unscheduled repairs and its life cycle cost. We improved the methods for determining the cost of unscheduled repairs, taking into account dependent failures and the coefficient of assessment of the effect of dependent node failure on the locomotive maintenance system. The proposed coefficient will determine the nodes, the failure of which affects the renewal cost more than their nominal value. It will also help to take into account the probable losses due to node failure during the development and adjustment of the locomotive maintenance system. Originality. For the first time, it is proposed to use the concept of the effect of dependent failures to calculate the locomotive renewal cost when performing unscheduled repairs, as well as the locomotive life cycle cost. Practical value. The improved calculation method for determining the cost of unplanned repairs with account taken of dependent failures can be used to compare and evaluate different variants of the locomotive maintenance system and to develop the locomotive diagnostic systems.

Design, Prototyping and Performance Evaluation of a Bio-inspired Walking Microrobot

This paper presents the development of a small and lightweight differential hexapedal microrobot, inspired by cockroach locomotion mechanism. Detailed design, prototyping and performance evaluation are reported in this paper. The manufacturing process of the microrobot uses Smart Composite Microstructure method by employing origami-inspired techniques. Each leg of the robot has 2-DoF in Cartesian space and uses cockroach mechanism in its configuration with lightweight moving parts. This microrobot deploys an on-board power source and control system architecture which offers the advantage of self-stabilizing in a horizontal plane, head orientation control and stair climbing capability that have not previously been reported in the literature. A prototype of the microrobot has been constructed and was evaluated at different terrains.

Fault-Tolerant Architecture of Storage Device for On-board Spacecraft Control Systems

For on-board microelectronic control systems of spacecraft with a long service life, the problem of increasing the fault tolerance of storage devices and ensuring ease of maintenance is solved. The architecture of a fault-tolerant storage device with built-in self-testing and automatic recovery from multiple failures is proposed.

Сравнительный анализ бортовых электронных систем управления грузовых автомобильных транспортных средств отечественного и иностранного производства

Сравнительный анализ бортовых электронных систем управления грузовых автомобильных транспортных средств отечественного и иностранного производства

Evaluation of the technical level of the agricultural tractor TK-3-180 when it is included in the robotic complex

Is given. It is shown that «Agropilot» precision agriculture system ensures driving accuracy no worse than ± 0,05 m, the «Edelweiss» modular unified technical vision system allows to control an autonomous platform. The automated control system for shifting gears and ranges can operate in one of three modes: full automatic, semi-automatic and manual. The upper-level onboard information and control system provides automatic control of the machine-tractor unit in unmanned mode throughout the shift work. The influence of the technical level of the tractor on its performance, working speed and shift factor is considered. As a result of studies of the influence of the technical level of the tractor elements on the shift performance, it has been revealed that the design of the tractor can give an increase in productivity to 37,2 %.

A gas-atomized spray cooling system integrated with an ejector loop: Ejector modeling and thermal performance analysis

Spray cooling has proved to be the promising candidate for the scheme of extremely high heat flux dissipation. The largest innovation of this paper is to develop a novel fluidic organization to realize the application of an air-oriented spray cooling system, considering the operating specialty of the air vehicle. Since an easy availability of the high-pressure air, an air-activated ejector and a gas-atomized nozzle rather than the normal high-pressurized liquid-driven nozzle are adopted. The ejector functions as a pump to collect and recycle the sprayed coolant under various gravitational fields, which is critical for the durable operation of the system. Design procedures of the ejector are developed, based on which a practical ejector is fabricated to be installed in the ground-based system. Heat transfer experiments were organized since there is there is a lack of study on the gas-atomized spray cooling performance. The state of the input high-pressure air and water which is used to generate the spray flow was optimized according to the cooling performance. Basic thermal laws regarding the gas-atomized spray cooling are attained. The highest the heat flux was 885.4 W/cm2 with a surface temperature of only 85.1 °C which justifies its future application of onboard thermal control system.

Analysis of logic-time characteristics of subsystem supply functioning hardware elements of unmanned aerial vehicles

To obtain the logical and temporal characteristics of the model of control loop process variable, an analysis of the subsystem hardware of the autonomous unmanned object onboard control system was conducted. The problem of time delays in the information transmission from the primary converter to the control element in automated process control systems is considered as equivalent of the subsystem of the onboard control system of an autonomous unmanned object. At present, there are no methods for estimating the effect of time delays of an information signal on the response time of a control loop, which leads to inefficient use of system resources. The increased time interval between the change in the process variable and the control effect can also lead to negative consequences. Parametric identification of individual nodes with subsequent compilation of a closed loop model by a separate parameter is selected as a tool for system analysis.

Construction of Highfailurestable Spacecraft Control System with Apply to Adaptive Logic in Diagnostic and Testing Algorithms

Different approaches to problem of improving onboard spacecraft control system failurestable on base principles of analytical excess, optimization and reconfiguration with using probability index and adaptive logic in diagnostic and testing algorithms are considered. One of problem is synthesis of spacecraft control system algorithms with incomplete apriory and distorted current information, action of uncontrolled and random factors, equipment failures and signal loss in information channel. Ways of failure diagnostic are examinated, in particular, problem excluding of failures sensors and power drives. Onboard attitude control system is synthesized and control algorithms are chosen, which guarantee robust stability and failure stability in presence indignant factors. Questions of onboard spacecraft control system failurestable improving are discussed on base reconfiguration with apply to adaptive logic in diagnostic and testing algorithms. The features of simulation are described on instrumental structure and operational modes of the attitude control system, the methods of dynamic research and computer simulation utilized during designing are indicated. Onboard complex control algorithms, diagnostic and reconfiguration are proposed for navigation, communication, geodesy satellites and earth inspectoral vehicles with prolonged utilization (more 10 years) in space flight conditions. Testing system have to decide two problem: discovering and eliminating faults. The mathematical system model is researching with implementation of analytic reserving. Difference signals are formed, which arise at fault appearance. The failure character is established by deciding rules on base difference signals and measures to it eliminating are took. The adaptive approach to development testing and diagnostic systems provide for realization of flexible logic of control system function to take into account factual onboard equipment state. The effectiveness of prepositional approaches and algorithms is confirmed by mathematical modeling results for several actual technical systems. Recommendations to their practical applications are gave.

Operation-oriented reliability and availability evaluation for onboard high-speed train control system with dynamic Bayesian network

The reliability and availability of the onboard high-speed train control system are important to guarantee operational efficiency and railway safety. Failures occurring in the onboard system may result in serious accidents. In the analysis of the effects of failure, it is significant to consider the operation of an onboard system. This article presents a systemic approach to evaluate the reliability and availability for the onboard system based on dynamic Bayesian network, with taking into account dynamic failure behaviors, imperfect coverage factors, and temporal effects in the operational phase. The case studies are presented and compared for onboard systems with different redundant strategies, that is, the triple modular redundancy, hot spare double dual, and cold spare double dual. Dynamic fault trees of the three kinds of onboard system are constructed and mapped into dynamic Bayesian networks. The forward and backward inferences are conducted not only to evaluate the reliability and availability but also to recognize the vulnerabilities of the onboard systems. A sensitivity analysis is carried out for evaluating the effects of failure rates subject to uncertainties. To improve the reliability and availability, the recovery mechanism should be paid more attention. Finally, the proposed approach is validated with the field data from one railway bureau in China and some industrial impacts are provided.

CubeSat onboard control system on the base of "system-on-chip" technology

CubeSat onboard control system on the base of "system-on-chip" technology