Automatic Speed Control Research Articles

Research on the Control Strategy of Leafy Vegetable Harvester Travel Speed Automatic Control System

This paper used the 4UM-120D electric leafy vegetable harvester as the research object and designed a travel speed automatic control system to maintain the travel speed within a set value of ±2% in order to improve the efficiency and quality of leafy vegetable harvester operations and decrease the work intensity of the operator. The harvester’s travel speed was automatically controlled by using the PID, adaptive fuzzy PID, and sliding mode control techniques after the mechanical and electrical equations for the travel drive motor (a DC brushless motor) were established in MATLAB. By simulating various working situations, the stability, accuracy, and speed of the automatic control system were compared and analyzed using the adjustment time, overshoot, steady-state transition time, and maximum deviation from the set speed as evaluation indicators. The test results revealed that when the current value of the leafy vegetable harvester travel speed deviated from the set value by more than 2%, the dynamic response performance and stability of the DC brushless motor travel drive system based on the sliding mode control strategy was significantly better than that of the PID and adaptive fuzzy PID control strategies, and its anti-disturbance was stronger, achieving the function of automatic control of the harvester travel speed. When the travel motor started with a constant load and the sliding mode control strategy’s parameters were the gain factors A = 1/70, c = 100, ε = 100, and k = 100, the travel drive system regulation time was 1.5 s, and the overshoot was 10%. When the harvester was operating smoothly and had leafy vegetable collection baskets loaded and unloaded, the steady-state transition time was 0.3 s. According to the actual engineering application experience, the specific technical state of the control strategy of the agricultural machinery travel speed automatic control system was: regulation time 2.5~3 s; overshoot amount 20~25%; and steady-state transition time 1.0~1.5 s, so the travel speed automatic control system of the electric leafy vegetable harvester in sliding mode was in line with the technical state requirements. The results of the field trials demonstrated the accuracy of the simulation test results. This study offered a method to lessen the work intensity of operators and increase the operating efficiency and quality of a leafy vegetable harvester.

Effects of automated speed control on speeding intention and behavior on mixed-traffic urban arterial roads

Although the effectiveness of automated speed control (ASC) has been proven, the mechanism of behavioral change in developing countries remains unclear. The objective of this study was to elucidate the effect of ASC on drivers' speeding intention and behavior on mixed-traffic urban arterial roads. Before and during the implementation of ASC, questionnaires based on the theory of planned behavior (TPB) were administered to local passenger-vehicle drivers. A total of 200 participants with an average age of 38.4 years completed both survey waves. To explain the mechanism of behavioral change, the multiple indicators multiple causes (MIMIC) structural equation modeling (SEM) time-invariant was used simultaneously for both waves. The model explained 49% and 55% of the variance in intention, and 40% and 56% of the variance in self-reported speeding behavior, respectively, before and during the ASC implementation period. The findings reveal that ASC altered the cognitive factors of speeding behavior. Speeding became less favorable, had lower approval, and was more difficult to control. Drivers reported lower speeding tendency and diminished speeding behavior. Furthermore, the ASC changed the relative impact of the factors, boosted the influence of family members and close friends on drivers' speeding motivation, and increased the influence of intention and perceived control on speeding behavior. This paper provides recommendations for the implementation of ASCs on mixed-traffic urban arterial roads in developing countries.

Design and Implementation of an Automatic Speed Control System of Vehicles for Avoiding Road Accidents in Bangladesh

Road accident has been a major problem in Bangladesh in recent years. An automatic speed control system is proposed in this paper to reduce road accidents by controlling the speed of the vehicle automatically. The main idea of the proposed system is to design a speed control system where the vehicle can adjust the speed depending upon the speed limit of the road. The designed system includes a sensor unit, a microcontroller unit and a functional unit. In the sensor unit, different sensors are used to perceive information to control the speed of vehicles. In the functional unit, a throttle automation system and brake automation system are introduced. This functional unit is mainly based on an electrical throttle control mechanism. Finally, the microcontroller is applied for taking decisions regarding the speed control of vehicles. This system shows a good prospect for speed control of the vehicles. Thus, it can able to reduce road accidents in Bangladesh.

Application of electromagnetic continuous variable transmission in hydraulic turbines to increase stability of an off-grid power system

In the context of climate change, today's adoption of renewable energy sources in isolated power systems is becoming an increasingly more significant issue. Micro-hydro power plants are emerging as a mature balancing technology and a great alternative to large hydropower plants as they do not encounter population displacement and many environmental problems. It is worth noting that hydroelectric power plants combined with various sources require improvement in control laws and algorithms. Strong disturbing impacts, namely transient processes, in an isolated electric power system cause an appreciable decrease in dynamic stability. This paper presents research conducted to ensure synchronous parallel operation of permanent-magnet generators used in micro-hydroelectric power plants in an isolated power system with a controllable flexible coupling between turbine and generator. The importance of this study lies in the issue of electromechanical compatibility to be achieved in parallel operation of generators that have different parameters of time constant of mechanical inertia of rotors of electrical machines. This paper provides an overview of possible solutions to the identified problem. A concept based on a controllable flexible coupling between generator and turbine is proposed as a promising avenue to solve this problem. The mathematical models are presented along with the laws and algorithms developed for automatic control of the generator speed. Oscillograms of simulation and physical modeling presented in the final part of the paper show parallel operation of permanent-magnet synchronous generators in an isolated electric power system for various electrical distances of three-phase short circuit points.

Automatic VLP’S Recognition For Smart Parking System

The system is designed as the authorized automatic vehicle identifier with respect to vehicle owner identification, for the security of the highly restricted areas like housing areas, defence military areas, parliament areas etc. Both of the number plate recognition and the vehicle owner recognition use the image identification technology. The image of the vehicle plate number and the vehicle owner are captured by using a camera and processed with MATLAB. The system contains an embedded section which controls the opening of the security gate and the communication purpose. The user interface provided at the entry/exit gate gives visual assistance to the driver, whether he/she is not permitted at this area or permitted. The entry of the unauthorized vehicle is restricted and the message is sent to the actual vehicle owner which is preregistered in the systems‟ database. The technology adopted in this research can be utilized not only for the security but also in other fields such as parking fee collection, automatic speed control, tracking stolen cars, automatic toll management and access control to limited areas, etc.

Automatic Speed Control of Motor with Over Current and Thermal Protection

This paper aims to design a controller to minimize the accidents of mechanical failure of industrial generators and motors under heavy load or malfunction. The controlling parameters such as the speed of motor is done via controlling the voltage and current fed to the motor. The speed control can be possible by using PWM technique. The factors which affect the motor can be sense using temperature and current sensor. The system also utilizes Over current & Thermal based backup protection scheme for failure protection.

ES-DQN: A Learning Method for Vehicle Intelligent Speed Control Strategy Under Uncertain Cut-In Scenario

Uncertain cut-in maneuver of vehicles from adjacent lanes makes it difficult for vehicle's automatic speed control strategy to make judgments and effective control decisions. In this paper, an intelligent speed control strategy for uncertain cut-in scenarios is established based on a basic autonomous driving system. This strategy judges cut-in maneuver from surrounding vehicles and outputs adaptive control action under current environment according to Q value of state-action pair based on a Q network. In addition, according to the analysis of cut-in scenarios, the Q network is trained based on a novel reinforcement learning method named as experience screening deep Q-learning network (ES-DQN). The proposed ES-DQN is an extension of double deep Q-learning network (DDQN) algorithm, and includes two parts: experience screening and policy learning. Based on the experience screened from the experience screening part, the proposed learning method can train an intelligent speed control strategy which has stronger adaptability and control effect in uncertain cut-in scenarios. According to simulation results, the proposed intelligent speed control strategy trained by ES-DQN has better performance under uncertain cut-in scenarios than DDQN method and traditional ACC strategy. Meanwhile, by adjusting weight value in reward function, the system can realize different control target.

Design of semi-Z source inverter topology with reduced number switches for four quadrant control of direct current motor

This paper proposes a novel approach to 4-quadrant speed control of a direct current (DC) motor based on the use of a semi-Z source inverter which has 2 active switches and 2 switching states. The semi-Z source inverter topology is analyzed for design purposes and results and relationships are discussed. The objective of this simulation is to design and analyze the performance of closed loop speed control of a DC motor using a semi-Z source inverter under realistic operating conditions. The findings of this project can be useful for designing several household appliances as well as systems like lathe machines, hoists, conveyors, and fans. Closed loop system designed for automatic speed control of a DC motor is obtained by using MATLAB/Simulink. The simulation results show that the proposed system works as intended.

Evaluation of low-cost GNSS receivers for speed monitoring

Accidents caused by exceeding the driving speed limit are one of the main reasons for premature deaths and permanent injuries worldwide. As such, the search for actions seeking to reduce traffic accidents or their severity becomes increasingly crucial as these accidents become more relevant. The objective of this work is to present a low-cost solution based on the GNSS (Global Navigation Satellite System) technology for vehicle monitoring and detection of road sections where drivers exceed speed limits. This allows classifying roads by their driver’s behavior, helping traffic authorities to manage these road sections. For this purpose, two devices were developed to measure GPS speed and to ensure the same tracking conditions for these devices. A fixing structure was built to accommodate the devices as well as a smartphone, which recorded the speedometer on video. Considering that the spatial data analysis showed no significant difference in speed measurements, the device can be chosen by the lowest cost. The comparison of measured speeds with devices in relation to speeds considered by traffic laws showed that device present values are closer to the vehicle speedometer (mainly at slower speeds). These results indicate that the sensation of speed difference on the part of the driver is considerable, and that tolerances established by the legislation need to be revised so as not to cause a feeling of impunity. Therefore, the use of low-cost GNSS receivers in automatic speed control and monitoring applications in road vehicles shows great potential. It is of great value especially on roads with tracking conditions similar to our experiments. This potential can be explored by educational measures to modify the road geometric designs where excesses are frequently identified.

Rational Choice of a Basket for the Rotational Vibropriller

The use of processing units for the production of mineral fertilizers in the industry in today’s market requires improved product quality and increased productivity. As a result, there is a need to change the design of existing units or some structural elements. Rotary vibroprillers, having a relatively simple design, can be of different designs that directly affect the productivity indicators mentioned above. The study considers the influence of the shape of the basket bottom on the quality of the rotational vibroprillers. After using the governing equation of prills motion in the airflow, a program was developed for automatic control of the rotational speed of the priller based on changes in melt loads. It is established that the size of the spray swath can be changed by varying the rotational speed of the priller. There is a tendency to affect the vibropriller performance by controlling the rotational speed and shape of the basket bottom without performance degradation.

НОРМЫ И МЕТОДЫ ОПРЕДЕЛЕНИЯ ЭЛЕКТРОМАГНИТНОЙ СОВМЕСТИМОСТИ СОВРЕМЕННЫХ СИСТЕМ АВТОМАТИЧЕСКОЙ ЛОКОМОТИВНОЙ СИГНАЛИЗАЦИИ И ЭЛЕКТРОПОДВИЖНОГО СОСТАВА С АСИНХРОННЫМ ТЯГОВЫМ ПРИВОДОМ НА МЕТРОПОЛИТЕНЕ

The article provides a brief overview of the development and application of automatic control systems for subway trains. Modern automatic locomotive signaling systems featuring automatic speed control with signal transmission based on double-phase-diff erence modulation are analyzed. The introduction of electric rolling stock with an asynchronous traction drive and advanced train traffi c automation and remote control systems at the St. Petersburg Metro initiates the drive to ensure their electromagnetic compatibility. For the subway train traffi c automation and remote control systems, there have been no acceptance criteria for electromagnetic interference that occur in their operating range when electric rolling stock with an asynchronous traction drive is put into operation. The article identifi es the main sources of conducted electromagnetic interference and the routes of their penetration into the receive path of automatic locomotive signaling devices with automatic speed control. A method is proposed for determining the limits of hazardous and interfering eff ects (immunity limits) for automatic train signaling systems with automatic speed regulation of the systems of the BARS automatic speed control unit with phase-diff erence modulation and the upgraded PA-M (ПА-М) train automation with phase-diff erence modulation for the St. Petersburg Metro lines. A method is given for the transition from the immunity limits of automatic locomotive signaling systems with automatic speed control to the emission limits of electric rolling stock at diff erent traction current unbalance factors. A technique for measuring traction current at high-potential points on electric rolling stock is considered. A technique for assessing the levels of conducted electromagnetic interference from electric rolling stock by calculating the eff ective value in a sliding window of a pre-fi ltered traction current signal of an electric rolling stock is presented.

Оптимизация автоматического регулирования частоты вращения судового дизеля

Annotation – The well-established method of tuning the speed governors (SG) of diesel engines during their operation under conditions of step disturbances, which are characteristic of diesel-generators, cannot be used for the main marine engines, the dynamic modes of which are associated, first of all, with heavy seas, because disturbances cannot change stepwise both along the channel for setting the rotational speed and along the load channel. In this regard, the practical need for the development of a method for tuning the SG of the main engines, which takes into account the peculiarities of their operation in heavy seas, has been determined. The study simulates the automatic speed control system (ASC) of the main marine engine HYUNDAI – MAN B&W 6G70ME-C9.2 of the large crude carrier "GOLDWAY" with the AutoChief 600 electronic SG. The minimum of instability of the controlled parameter was used as an optimality criterion, i.e. the amplitude of the oscillations of the rotational speed of the diesel engine shaft, with the most probable values of the amplitude and period of oscillations (rolling) of the disturbing effect. The study has established that changing the tuning parameters of the governor may lead to local extrema of the optimality criterion when using an electronic governor in the ACS in the factor space of disturbances on a diesel engine, which are typical for heavy seas. It means that the task, requiring finding local extrema using specialized methods, can be set when using an electronic governor in the ACS. However, a significant decrease in the instability of the rotational speed was achieved by carrying out a simple enumeration of the tuning parameters of the SG. It was also found that with a "heavy" propeller, the rotational speed stability can be increased by decreasing the proportional gain, as well as increasing the integrator time.

Development of an Automatic Elastic Torque Control System Based on a Two-Mass Electric Drive Coordinate Observer

Development of control system based on digital twins of physical processes is a promising area of research in the rolling industry. Closed-loop control systems are developed to control the coordinates of two-mass electromechanical systems in order to limit the dynamic loads on the equipment of main rolling lines. These control systems are based on observers (digital shadows) that indirectly detect (reconstruct) the roll speed and the elastic torque of the shaft (spindle) in real time. Notably, observers are required to work fast in order to reconstruct transients attributable to shock (impact) loads. Literature review shows that the known observers, which use complex algorithms to compute coordinates, do not respond fast enough. The paper analyzes the kinematic diagram of Mill 5000, a plate rolling mill. It presents oscillograms that prove that the elastic torque does oscillate as the rolls grip the strip dynamically. The authors hereof have developed an observer that reconstructs the coordinates of the uncontrolled mass (the shaft) and the spindle torque from the parameters of the controlled mass, namely the torque and speed of the motor. The paper further rationalizes an approach that consists of simulating the processes on a model to further directly configure them on the object. The authors analyze the transients of the reconstructed two-mass system coordinates, which are associated with the rolls gripping the strip. The paper compares data against oscillograms recorded on the mill itself. The accuracy is satisfactory. The proposed observer has been used to developed a three-loop automatic speed control system for the uncontrolled mass. Controller configurations are substantiated. The paper shows coordinates obtained by simulation modeling as functions of time. It further presents experiments run on Mill 5000; the conclusions are that the amplitude and oscillations of the elastic torque drop significantly. The paper concludes with recommendations on industrial adoption of the observer and the novel electric drive coordinate control system. Study presented herein substantiates and implements a concept of developing algorithms that solve specific problems and are readily implementable on the existing equipment without need for additional computing devices. The contribution of the paper consists of stating and solving the problem of developing and testing an automatic elastic torque control system for the shaft of a heavy-duty rolling mill. This system has been implemented in the form of algorithms that run in the software of the existing industrial controllers (PLCs). It is simple and performs well. It does not need additional sensors or computers to be implemented, nor does it rely on complex computational algorithms. Such algorithms are based on computational tables that require a priori data on numerous process parameters. In our literature review, we have not come across any industrial implementation of such algorithms on hot-rolling mills.

Effect of Localized Temperature Difference on Hydrogen Fermentation

In a lab-scale bioreactor system, (20 L of effective volume in our study) controlling a constant temperature inside bioreactor with a total volume 25 L is a simple process, whereas it is a complicated process in the actual full-scale system. There might exist a localized temperature difference inside the reactor, affecting bioenergy yield. In the present work, the temperature at the middle layer of bioreactor was controlled at 35 °C, while the temperature at top and bottom of bioreactor was controlled at 35 ± 0.1, ±1.5, ±3.0, and ±5.0 °C. The H2 yield of 1.50 mol H2/mol hexoseadded was achieved at ±0.1 and ±1.5 °C, while it dropped to 1.27 and 0.98 mol H2/mol hexoseadded at ±3.0 and ±5.0 °C, respectively, with an increased lactate production. Then, the reactor with automatic agitation speed control was operated. The agitation speed was 10 rpm (for 22 h) under small temperature difference (<±1.5 °C), while it increased to 100 rpm (for 2 h) when the temperature difference between top and bottom of reactor became larger than ±1.5 °C. Such an operation strategy helped to save 28% of energy requirement for agitation while producing a similar amount of H2. This work contributes to facilitating the upscaling of the dark fermentation process, where appropriate agitation speed can be controlled based on the temperature difference inside the reactor.

Система нечіткого автоматичного керування режимом руйнування вугіль-ного масиву виконавчим органом очисного комбайна

Up to now, automatic control of the shearer speed has been performed to keep the actual speed at an operator-specified level or to keep the actual power at a stable level without overheating or overturning. However, the problem of control of coal seam cutting by the upper drum of a shearer in the case of a variable angle of drum – coal seam contact has yet to be studied. The aim of this work is to develop a method for synthesizing a system of fuzzy automatic control of coal massif cutting by a shearer drum based on an information criterion for the power efficiency of coal cutting with cutters. In this work, based on an information criterion for the power efficiency of coal cutting with cutters, a fuzzy inference algorithm is constructed for a system of automatic control of coal massif cutting by a shearer drum. In doing so, the parameters of the output linguistic variable term membership functions of the system and fuzzy operations are determined according to the recommendations of the classical Mamdani fuzzy inference algorithm using substantiated fuzzy production rules. The fuzzy inference algorithm constructed in this work is tested for efficiency based on the fraction of effective control actions generated by the fuzzy automatic control system. Using simulation, the efficiency of drum rotation speed control with the use of the proposed fuzzy inference algorithm is compared with that with the use of an uncontrolled shearer cutting drive. The study of the generation of control actions involving the upper shearer drum rotation speed showed that effective control actions were generated in the overwhelming majority of cases (about 93%). The proposed method forms a theoretical basis for the solution of the important scientific and practical problem of upper shearer drum rotation speed control automation with the aim to reduce specific power consumption and the amount of chips.

Параметрическая оптимизация системы автоматического регулирования частоты вращения вала двигателя постоянного тока судна

DC motor speed control can be done either manually or by using an automatic controlling tool. In order to perform parametric optimization of a DC motor rotational speed automatic control system, we have developed a simplified methodology. The said methodology is able to obtain a transfer function for an automatic control system being based on several initially given system parameters. It is a tree-step way according to the research goals. We offer model patterns where parameters can be designated. Time constant for a PI controller is being presented by a process time constant for a controlled DC motor for the purpose of this particular research.

Design and Implementation of a Position, Speed and Orientation Fuzzy Controller Using a Motion Capture System to Operate a Wheelchair Prototype

The design and implementation of an electronic system that involves head movements to operate a prototype that can simulate future movements of a wheelchair was developed here. The controller design collects head-movements data through a MEMS sensor-based motion capture system. The research was divided into four stages: First, the instrumentation of the system using hardware and software; second, the mathematical modeling using the theory of dynamic systems; third, the automatic control of position, speed, and orientation with constant and variable speed; finally, system verification using both an electronic controller test protocol and user experience. The system involved a graphical interface for the user to interact with it by executing all the controllers in real time. Through the System Usability Scale (SUS), a score of 78 out of 100 points was obtained from the qualification of 10 users who validated the system, giving a connotation of “very good”. Users accepted the system with the recommendation to improve safety by using laser sensors instead of ultrasonic range modules to enhance obstacle detection.

Drivers' Real-Time Drowsiness Identification Using Facial Features and Automatic Vehicle Speed Control

The road crash is one of the significant problems that is of great concern in today's world. Road accidents are often caused by drivers' carelessness and negligence. The drowsy condition of the drivers, which occurs due to overwork, fatigue, and many other factors, is one of those causes. It is therefore most critical to establish systems that can detect the driver's drowsy state and provide the drivers with the appropriate warning system. In addition to the automatic speed control of the car, this system thus supports drivers in incidents by providing warnings in advance. This means that road collisions that are harmful to living lives are minimised. This is achieved by using the technique of image recognition, where driver drowsiness is observed, and using this method, simultaneous warning and speed monitoring of the vehicle is carried out.

WITHDRAWN: Automatic car speed control system

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Design and Implementation of Constant Speed control System for the Induction motors Using Programmable logic Controller (PLC) and Variable Frequency Derive (VFD)

This paper presents an automatic speed control system on three phase squirrel cage induction motor using Programming Logic Circuit (PLC) and Variable Frequency Drive (VFD) techniques. The aim of this study is to obtain a constant speed of induction motors when these motors are exposed to variable loads. The required speed of the induction motor can be set as a numerical value by (PLC), while the actual speed of the induction motor can be measured by a tachometer which is equipped with (PLC) ) Through an Analog to Digital Converter (ADC). Then the two speeds are compared to the set point with minimum error to get the required constant speed. The control system designed to be tested with two stator poles number (two and four poles) of induction motors. The results have cleared that in spite of doubled the load 11 and 8 times respectively, but the yield average shaft speeds are almost constant 2891.15 rpm and 1402.45 rpm respectively.