Microprocessor-based Control System Research Articles

Design and Implementation of Green House Data Logger for Optimum Crop Production

Greenhouse technology is a viable option for sustainable crop production in regions of adverse climatic conditions. During hot seasons the heat input to a greenhouse causes the internal temperature to exceed its optimal value. The present study was devoted to constructing an evaporative cooling system to reduce heat stress inside a greenhouse. The use of greenhouses with controlled microclimate according to the plant's needs isan important way to increase the production of fruits and vegetables and has recently become one of the hottest topics in precision agriculture. To know and control the greenhouse microclimate, smart sensing nodes with wireless communication capabilities are recommended. This paper presents a review of the use of technologies for automated activities in greenhouses. Different microclimate parameters inside the greenhouse are to be precisely controlled for successful greenhouse cultivation or to maximize production. Controlling can be done either by manually or by an automatic control system which comprises measurement, data processing, recording and management of environmental parameters. The manual method of control is not accurate, very time-consuming and very laborious process. Hence automatic control of microclimate is required for better performance of the greenhouse. Different methods of automation of the greenhouse include the use of microprocessor-based control systems and computer-controlled systems. Computerized control is more accurate but not economical for small and medium farmers. Microprocessor-based control is good for small farmers

Разработка контроллера электромеханического датчика положения

Electromechanical position sensors, including sine-cosine rotary transformers, compared to sensors based on other physical principles, have greater reliability, a simple design and resistance to difficult operating conditions. This makes them attractive for use in various motion control systems that require measurement of the position of the actuator axis. However, the use of such sensors requires special hardware and software devices – controllers that ensure their operation. This article is devoted to the development of such a controller, which generates, captures, and processes signals of the sine-cosine rotary transformer. When developing the controller of the sine-cosine rotary transformer, methods of system analysis of electrical, electromagnetic and information processes and means of their implementation, methods of software development, as well as methods of experimental research were applied. A description of the controller of a sine-cosine rotary transformer in phase mode is given, taking into account the hardware and computing resources of the microcontroller which implements it. At the same time, physical processes are correlated with information processes associated with the generation, capture and procession of signals. The reasons for the decrease in the position measurement accuracy are revealed. Various technical solutions have been applied to take into account and eliminate them. Among them are the coordination of physical and information processes, taking into account the execution time of calculations by the microcontroller, analysis of the correctness of the position measurement results and their smoothing according to moving average method. The controller software has been developed, which can serve as a typical element for microprocessor-based control systems. Experimental results are obtained, illustrating the achievement of the development result. Application of various technical solutions has made it possible to ensure the accuracy of position measurement up to a tenth of a degree with a high intensity of information updating. As a result of the study, a detailed and comprehensive solution of the developing a controller for a sine-cosine rotating transformer problem is given, which is the scientific and practical value of the materials presented in the article. The results obtained can be applied in various motion control systems and serve as the basis for the development of controllers for various electromechanical position sensors.

Improving the temperature resistance of traction electric motors using a microprocessor control system for modern locomotives

Temperature control of traction electric motors running on direct current with the help of a modern microprocessor-based locomotive control system is analyzed in the paper. Development of a methodology for calculating the temperature of the windings of traction electric motors operating on direct current, based on a modern control system has been discussed. To determine the dependence of the temperature of traction motors on the motion profile and weight of the rolling stock.

Optimization of the Control of Electromagnetic Brakes in the Stand for Tuning Internal Combustion Engines Using ID Regulators of Fractional Order

This work is aimed at developing a stand for tuning the fuel system of an internal combustion engine based on two electromagnetic retarders connected to the driving wheels of a car to simulate a load, and a microprocessor-based torque control system for each brake. In accordance with the terms of reference from the specialists of the automotive service center, such a stand should provide two main modes of operation: (1) stabilization of the speed of the drive wheels in the entire range of loads (fuel supply); (2) engine acceleration and deceleration according to linear tachograms in the range from minimum to maximum speed to determine the dependence of engine power and torque on speed. The purpose of this research is the synthesis of controllers, testing, the choice of the structural scheme, and the parameters of the control and data processing system in the stand for the precision tuning of internal combustion engines. Based on a preliminary analysis of the system, taking into account the mechanical connection of the wheels through the main gear and the car differential, the nonlinear dependence of the electromagnetic torque on the current and retarder speed, and subsequent experimental results, we obtained two types of controller—a third-order aperiodic transfer function and a fractional aperiodic transfer function of order 1.6. This made it possible to synthesize a family of controllers that ensure the operation of the stand in the required modes: synchronization of wheel speeds during engine acceleration; stabilization of the reference speed when the engine torque is changed from minimum to maximum due to fuel supply; measurement of the maximum power and torque of the internal combustion engine during the formation of a triangular tachogram with a given acceleration to compensate for the dynamic component of the torque due to mechanical inertia. The system with the PID controller configured in MATLAB in the “Tune” package has the best performance, but the smallest overshoot and the best dynamic accuracy are ensured by the PIDIγIµ fractional–integral controller, where the system is characterized by a fractional order of astaticism 1.6. Such a controller for each electromagnetic retarder serves as the basis of the microprocessor-based control, data acquisition, processing, graphical display system, and will also be used to develop a similar bench for tuning four-wheel-drive vehicles.

Designing of a Micropump System for Circulatory Support

Introduction. Support systems currently used in modern cardiac surgery to provide partial or complete, permanent or temporary replacement of cardiac function are frequently characterized by large dimensions, thus requiring major surgical interventions. Low invasiveness can be ensured by reducing the size of the implanted part of such systems, allowing these devices to be inserted through the femoral artery.Aim. Development of a minimally invasive micropump system to support blood circulation.Materials and methods. Based on the analysis of implementation of micropump circulatory support systems (MCSS), the configuration, operational principles and main components of such a system were determined. When designing a micropump, as a unit defining the weight and size parameters of the entire system, numerical and experimental methods were used to optimize its flow path based on the condition of minimizing blood injury and thrombus formation. The lubrication and cooling system was developed by solving the thermodynamic problem of heat removal. The electronic control unit was developed on the basis of accumulated experience in the design and operation of control units for circulatory support systems.Results. A micropump with a diameter of 6.5 mm and a length of 43 mm with the required hydro- and hemodynamic parameters was designed. The device ensures minimal trauma and thrombus formation. The main MCSS parameters, as well as its main components (electric drives, lubrication and cooling systems), were defined. The configuration and operational principles of the electronic control unit (ECU), consisting in a microprocessor-based control system with feedback, were developed. The ECU built-in software manages the rotational speed of the electric drives of the micropump and coolant supply pump in the required range. In addition, the software is used to measure, display and register the MCSS operational parameters, as well as to monitor their operation in the required ranges and to exchange data between the ECU and the PC.Conclusion. All the necessary documentation for the MCSS nodes and components was prepared. These nodes and components ensure the hydro- and hemodynamic parameters required for the use of the developed minimally invasive micropump system. Future work will address the stages of MCSS assembly and debugging.

Performance of an auto-adjusting prosthetic socket during walking with intermittent socket release.

IntroductionA challenge in the engineering of auto-adjusting prosthetic sockets is to maintain stable operation of the control system while users change their bodily position and activity. The purpose of this study was to test the stability of a socket that automatically adjusted socket size to maintain fit. Socket release during sitting was conducted between bouts of walking.MethodsAdjustable sockets with sensors that monitored distance between the liner and socket were fabricated. Motor-driven panels and a microprocessor-based control system adjusted socket size during walking to maintain a target sensed distance. Limb fluid volume was recorded continuously. During eight sit/walk cycles, the socket panels were released upon sitting and then returned to position for walking, either the size at the end of the prior bout or a size 1.0% larger in volume.ResultsIn six transtibial prosthesis users, the control system maintained stable operation and did not saturate (move to and remain at the end of the actuator’s range) during 98% of the walking bouts. Limb fluid volume changes generally matched the panel position changes executed by the control system.ConclusionsStable operation of the control system suggests that the auto-adjusting socket is ready for testing in users’ at-home settings.

Smart Security System for Theft Protection Using Face Recognition

The number of car robbery attempts at the local and international scale is rising rapidly in this modern era. By inventing robbery techniques, the owners are afraid that their cars will be robbed from their ordinary parking lot or from outside. This makes vehicle protection against robbery important as a result of insecurity. The computer vision based real-time vehicle safety system solves this problem. The proposed car safety system carries through real time user authentication based on image processing using face detection and recognition techniques and a microprocessor-based control system attached to the car. The infrarot sensor attached to the driver's vehicles seat activates the hidden camera, which is fixed inside the vehicle, as the person enters the parked vehicle overcoming the existing security features. The person's face is detected using Viola Jones algorithm once the image is obtained from the activated camera. The extracted face is recognized using the improved Linéar Discriminant Analysis (LDA) algorithm that distinguishes many features rather than looking for an exact pattern based on the Euclidean distance. Authorization requires that the threshold value is established and compared to the Euclidean distance over which the person is not authenticated. The face is sent to the mobile of the owner as an MMS via the operating GSM modem, which is classified as unknown. The owner shall be controlled with the relay in accordance with the owner’s command when the information is received. The way to authenticate the person would be efficient and efficient in terms of vehicle safety.

Monitoring the Technical Condition of AC Electric Locomotives using Traction Energy Consumption Rates

Currently, the methods of monitoring the technical condition of locomotives using data of on-board microprocessor-based control systems are widely used. This monitoring of Russia has become an operating technology of the locomotive maintenance and repair system.The main problem of monitoring is the limited set of sensors in locomotive circuits. Increased number of sensors leads to a decrease in reliability and to an increase in the cost of a locomotive and of its life cycle, while allowing to achieve better quality of diagnostic information.Besides, it is advisable to have integrated indicators of the technical condition of a locomotive. The article presents a computer software product for analysing the technical condition of a locomotive based on dynamic data on consumption of traction active power and generation of reactive power. The software was developed by using algorithmic language Visual BASIC for Applications, embedded in MS Excel, using probabilistic and statistical methods of analysis.The method for diagnosing the technical condition of a locomotive within the monitoring system is based on a comparison of dynamics of consumption of active and generation of reactive power by two sections of the same locomotive according to the principle of functional benchmarking. For monitoring the technical condition of locomotives, the term «pre-failure» is suggested, which is defined as the operable condition of a locomotive while there are internal hidden defects or damage. Pre-failure manifests itself in power consumption. To analyse the technical condition of AC electric locomotives in terms of electricity consumption, the initial data must have a high degree of unimodality, which is determined by uniformity of operating conditions.The resulting data obtained following the analysis of the technical condition of a locomotive based on the dynamic data on consumption of tractive active energy and generation of reactive power can be used to determine a defect that causes a change in consumption of electricity at the moment when the locomotive enters technical maintenance and repair depot. *Information about the authors: Semenov, Alexander P. – Ph.D. (Eng), General Director of JSC Research Institute of Technology, Control and Diagnostics of Railway Transport, Omsk, Russia, corp@niitkd.ru. Semchenko, Victor V. – Ph.D. (Eng), General Director of JSC Railroad Centre of Technology Implementation of Krasnoyarsk Railway, Krasnoyarsk, Russia, office@dcv.ru. Khromov, Igor Yu. – Business Analyst of LLC2050-Integrator, Moscow, Russia, KhromovIYu@yandex.ru. Article received 13.05.2020, accepted 23.10.2020. For the original Russian text of the article please see p. 62.

Анализ подтверждения соответствия, обеспечение качества и безопасности микропроцессорных систем железнодорожной автоматики

The article analyzes the current regulatory framework for proof of safety, quality assurance, and confi rmation of the conformity of microprocessor-based railway automation and remote control systems in the EAEU. CENELEC standards are briefl y discussed. A brief overview is provided as regards measures to ensure the required level of safety of microprocessor-based railway automation and remote control systems from the point of view of quality management of development, safety management, and confi rmation of the proper functioning of microprocessor systems. The practice of confi rming the railway transport automated process control systems comply with standards in the form of a declaration of conformity per TR CU 003/2011 has been analyzed. It is concluded that there is a need to develop a regulatory framework to ensure regulated analysis and assessment of railway automation and remote control systems following the requirements of functional safety, as well as further development of standardization documents to regulate methods for assessing functional safety.

Микропроцессорные системы управления движением поездов в Московском метрополитене

Микропроцессорные системы управления движением поездов в Московском метрополитене

DEVELOPMENT OF A MICROPROCESSOR CONTROL SYSTEM OF GAS ICE WITH SEQUENTIAL GAS FUEL INJECTION

The advantage of using alternative gas motor fuels in particular liquefied oil gas by wheeled vehicles, in comparison with traditional liquid motor fuels is shown. The expediency of converting diesel wheeled vehicles into internal combustion gas engines with spark ignition for operation on liquefied petroleum gas has been substantiated. A microprocessor-based gas engine control system has been developed, consisting of two main subsystems and a microprocessor-based electronic control unit. The control system is capable of delivering LPG sequential injection without the need for a traditional camshaft position sensor and a special reference plate mounted on the camshaft. The principle of operation of the main gas engine systems, which include the power supply and injection of liquefied petroleum gas in the inlet nozzle of each cylinder, as well as a modified contactless electronic ignition system with a movable voltage distributor are described. A special «B» level Avenir Gaz 37 microprocessor electronic control unit has been developed and manufactured, which instead of information (signal) from the camshaft position sensor receives information (signal) about the camshaft position from a modified ignition system to implement sequential liquefied petroleum gas injection. Modification of the ignition system is carried out by finalizing the standard drive disk of the distributor. The rework was carried out by increasing the length of the arc of the circle sector of the first cylinder opening. Tests of the gas internal combustion engine of the D-240-LPG-«B» model with the developed microprocessor control system and Avenir Gaz 37 electronic control unit of the «B» level at idle modes for compliance with the requirements of standard 4277 have been performed. The test results showed that the gas engine D-240-LPG-«B» in terms of carbon monoxide and hydrocarbons in the exhaust gases meets the requirements of standard 4277 and has a significantly lower content than the maximum permissible for engines without catalysts.

Identifying and analyzing John Deere tractor trouble codes based on CAN bus

The article discusses modern technologies for diagnosing the technical condition of agricultural automotive equipment on the example of a John Deere tractor. A description of the John Deere tractor and electronic systems is given. Modern tractors are equipped with microprocessor-based control systems with diagnostic capabilities. This makes it possible to timely inform the operator about possible malfunctions of the working systems of the tractor, for example, the engine or brake system. The system of digital communication and control of the electric devices of the vehicle — the CAN interface — allows you to collect data from all devices, exchange information between them, manage them.

Performance Analysis of a Digitally Retrofitted Ward—Leonard Control Dragline—A Case Study in Coal Mine

Some of the coal mines use dragline for the overburden removal of coal top as its geometric, since the initial cost is high with low running cost. Most of the draglines operating in Indian mines have conventional analog control under Ward???Leonard method. To improve the efficiency of those, to reduce the power consumption and to provide maintenance-less operation in the electrical system, the microprocessor-based digital control system is proposed to replace the analog method of control. This paper analyzes and presents a case study of real time performance of one upgraded digitally controlled Ward???Leonard dragline, operating in an Indian mine-field. It shows the improvement in specific energy consumption and suggests maintenance issues based on the comparative study of breakdown status before and after the upgradation.

Modern Locomotive Traction Drive Control Systems

The increasingly strict requirements that are being placed on transportation safety and traction rolling stock automation makes necessary the development of microprocessor-based control systems. Currently, a significant part of the locomotive fleet uses a rheostat–contactor traction motor control system that was developed more than a century ago, and the use of accelerating resistors is leading to significant losses of electricity. This control system functionality does not correspond to the current technological level. This paper considers the use of digital control systems for electric rolling stock and their advantages. It is shown that the use of digital technologies in the design of traction drive power converters will significantly increase the energy efficiency of the converters, reduce the number of components and increase the traction drive reliability.

SIMILE OF INDICATORS OF WORK OF VARIOUS SPEED REGULATORS ON AUTOMOBILE DIESEL

The purpose of the research is to compare the quality indicators of the speed regulation of an automobile diesel with an all-mode mechanical regulator of direct action and an all-mode microprocessor regulator of indirect action on steady and transient regimes. Motor comparative researches were carried out on the same 4-cylinder automobile diesel with turbocharging (cylinder diameter 120 мм, stroke 140 мм). The object of experimental research is an automatic serial mechanical and microprocessor-based automotive diesel engine control systems developed by the authors. The results of digital records allows to visually assess the quality indicators of the speed regulation and adjustment of speed regulators. The results of the comparative analysis show the satisfactory operation of the developed all-mode microprocessor controller in various steady-state and dynamic modes and confirm the necessity of tuning the PID parameters depending on the operational mode of operation of the diesel engine. It is established that the stability of maintaining the rotational speed of the developed all-mode microprocessor regulator at different steady regimes ща speeds does not exceed 5 %. The values of the casting speed and the duration of the transient processes are no worse than using a serial mechanical regulator.

Моделирование вентильно-индукторного электровибропривода

The article deals with the issue that there is no study on designing switched reluctance electric vibration drives. Mathematical models of electromechanical converter and electronic commutator with 90-degree motor phase commutation algorithm are presented. The interdisciplinary calculation of the built models was carried out. The results of modeling and simulation are motor windings currents and induced voltage graphs. The expe­rimental prototype of the switched reluctance vibration drive with the microprocessor-based control system is developed and manufactured. The experimental research that proves the models adequacy has been performed.

Malicious Firmware Detection with Hardware Performance Counters

Critical infrastructure components nowadays use microprocessor-based embedded control systems. It is often infeasible, however, to employ the same level of security measures used in general purpose computing systems, due to the stringent performance and resource constraints of embedded control systems. Furthermore, as software sits atop and relies on the firmware for proper operation, software-level techniques cannot detect malicious behavior of the firmware. In this work, we propose ConFirm, a low-cost technique to detect malicious modifications in the firmware of embedded control systems by measuring the number of low-level hardware events that occur during the execution of the firmware. In order to count these events, ConFirm leverages the Hardware Performance Counters (HPCs), which readily exist in many embedded processors. We propose a comparison-based technique to detect malicious modifications in firmwares with simple control-flows. For firmwares with more complex control-flows, we use machine learning techniques to automatically extract the relations among different hardware events. This method significantly reduces the number of pre-stored valid HPC signatures without compromising the detection accuracy. Finally, we reduce the consumption of local resources by implementing a remote-based detection mechanism. We evaluate the detection capability and performance overhead of the proposed technique on various types of firmware running on ARM- and PowerPC-based embedded processors. Experimental results demonstrate its practicality and effectiveness.

Development of Microprocessor-based Car Engine Control System

Based on the analysis of gearboxes designs a microprocessor-based car engine control system is developed, which allows semi-automatic or automatic gear shifting, thus facilitating driving, decreasing the fuel consumption, increasing the durability of transmission. The microprocessor-based control system of the car engine, which allows the automatic synchronization of angular speeds of entrance and output power stream, and carrying out gear shifting without switching off the clutch was described. The block diagram of microprocessor-based car engine control system, the construction of electro-pneumatic actuator and photo of the gearbox with the executive mechanism was presented.

Simulation of Traction Electric Drive with Vector Systems of Direct Torque Control

The article deals with investigation of electromechanical and energetic characteristics of traction electric drive with vector systems of direct torque control. As a controlled object the traction asynchronous motor ДТА-1У1, which is used to drive the trolley-bus is considered. At the present time the usage of traction asynchronous electric drives for town transport is relevant. Due to development of power electronic devices and microprocessor-based control systems it became possible to replace DC electric drives with electric drives with asynchronous motors. The article contains brief description of two different types of control systems: field-oriented control (FOC) and direct torque control (DTC). Principles of work for both systems are considered and the main advantages and disadvantages associated with the use of these systems are pointed out. The models of both systems for traction asynchronous electric drive, built in modeling environment MATLAB/Simulink, are given in this article for further comparative analysis. As the main quality factor of control total harmonic distortion (THD) is used.

Fabrication of fibrous patterned architectures with controlled deposition and multidirectional alignment

In recent years, the ability to produce nanofibrous patterned architectures by electrospinning has exposed a wide range of potential applications in biomedical and industrial fields. Directional alignment, controlled deposition, and density variation into the patterns are desirable for many applications such as tissue engineering scaffolds and micro/nano‐electronic devices. In this study, we introduce a versatile method for fabrication of various kinds of nanofibrous deposition patterns with the help of microprocessor based control system for switching collector electrodes. By controlling the concurrent activation time of two adjacent electrodes, we demonstrated that amount of fibers going into the pattern can be adjusted and alignment in electrospun fibers can be obtained. We also revealed that the deposition density of electrospun fibers in different areas of patterned architectures can be varied. This advanced technique can have a significant impact in enhancing the technology of electrospinning and can help develop new applications in health sciences and industrial sectors. Copyright © 2015 John Wiley & Sons, Ltd.