Name: feedback in everyday control systems
Uploaded: 2024-09-26T13:17:14.000Z
Duration: 1 min 10 s
Channel: JoVE

K12 Standards

new-jersey-student-learning-standards-for-science

New Jersey Student Learning Standards for Science

High School

Physical Science

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Waves and Their Applications in Technologies for Information Transfer

HS-PS4-5

Control Systems

Les systèmes de contrôle influencent de nombreuses applications, des navettes spatiales à la fabrication automatisée. Ils existent naturellement, comme la régulation de la glycémie de notre corps et les ajustements de la fréquence cardiaque pendant le stress.
Ces systèmes se composent de sous-systèmes et de processus produisant des résultats spécifiques à partir d’entrées données.
Prenons l’exemple d’un ascenseur : un passager appuyant sur un bouton déclenche une entrée dans le système de contrôle, le dirigeant vers l’étage souhaité.
Les performances du système, indiquées par la vitesse de l'ascenseur et la douceur de conduite, sont mesurées à l'aide de la réponse transitoire, de la réaction du système aux changements et de l'erreur d'équilibre, c'est-à-dire la disparité entre la sortie réelle et la sortie souhaitée.
Les variables contrôlées sont mesurées et régulées ; des signaux de commande guident ces changements.
Les usines sont les objets physiques contrôlés, et les processus sont les opérations sous contrôle.
Les systèmes combinent des composants pour un objectif, et les perturbations affectent la production. Le contrôle de rétroaction maintient l’équilibre en réduisant les différences entre la sortie et la référence.

les systèmes de contrôle

Les systèmes de contrôle sont omniprésents dans la société contemporaine, influençant diverses applications, de l'aérospatiale à la fabrication automatisée. Ces systèmes se retrouvent naturellement dans les processus biologiques, tels que la régulation de la glycémie et l'ajustement du rythme cardiaque en réponse au stress, ainsi que dans les systèmes fabriqués par l’homme, tels que les ascenseurs et les véhicules automatisés. Un système de contrôle est essentiellement un réseau de sous-systèmes et de processus qui convertissent ensemble des entrées spécifiques en sorties souhaitées.


Au cœur de tout système de contrôle se trouvent plusieurs éléments clés : la variable contrôlée, le signal de contrôle, les usines, les processus, les systèmes, les perturbations et les mécanismes de contrôle par rétroaction. La variable contrôlée est le paramètre que le système vise à réguler. Le signal de commande est la directive envoyée au système pour modifier la variable contrôlée. Les installations font référence aux entités physiques gérées au sein du système, telles que les machines dans une usine ou le cœur humain dans un contexte biologique. Les processus englobent les opérations qui se déroulent au sein de l'usine, la conduisant vers le résultat souhaité. Le système lui-même est un assemblage structuré de composants travaillant vers un objectif spécifique. Les perturbations sont des facteurs externes qui peuvent influencer les performances du système en provoquant des écarts par rapport au résultat souhaité. Le contrôle par rétroaction joue un rôle crucial en surveillant en permanence la sortie du système et en effectuant les ajustements nécessaires pour minimiser la différence entre la sortie réelle et l'entrée de référence.


Prenons l'exemple d'un ascenseur. Lorsqu'un passager appuie sur un bouton, cette action sert d'entrée au système de contrôle, qui traite ensuite cette entrée et dirige l'ascenseur vers l'étage désigné. Les performances du système d'ascenseur sont évaluées à l'aide de deux critères principaux : la réponse transitoire et l'erreur en régime permanent.


La réponse transitoire est la réaction du système aux changements, tels que le mouvement initial de l'ascenseur lorsqu'on appuie sur un bouton. L'erreur en régime permanent est la différence entre la position réelle de l'ascenseur et la position souhaitée une fois que le système s'est stabilisé. La fluidité du trajet de l'ascenseur et sa vitesse sont des indicateurs de l'efficacité et de la précision du système.


Le contrôle par rétroaction est un aspect essentiel des systèmes de contrôle modernes. Il garantit que la sortie reste cohérente avec l'entrée souhaitée malgré les perturbations. Il fonctionne en comparant la sortie réelle à l'entrée de référence et en effectuant des ajustements en temps réel pour réduire les écarts. Ce mécanisme d'autocorrection est essentiel pour maintenir la stabilité et obtenir un contrôle précis dans les systèmes naturels et techniques.


En comprenant et en optimisant ces composants, les ingénieurs de contrôle peuvent concevoir des systèmes robustes, efficaces et capables d'effectuer des tâches complexes avec une grande précision. Cette compréhension est à la base des progrès réalisés dans de nombreux domaines, des soins de santé à l'automatisation industrielle, soulignant le rôle essentiel des systèmes de contrôle dans la technologie moderne.

Les systèmes de contrôle

Les systèmes de contrôle influencent de nombreuses applications, des navettes spatiales à la fabrication automatisée. Ils existent naturellement, comme la glycémie de notre corps...

Education

Enseignement

JoVE Core

Electrical Engineering

Génie électrique

Unit 1

Unité 1

Introduction to Control Systems

Introduction aux systèmes de commande

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

feedback in everyday control systems

Control systems use feedback to keep a variable close to a desired value. They appear in both natural and engineered settings. Examples include blood sugar regulation, heart rate changes during stress, elevators, automated vehicles, aerospace systems, and automated manufacturing.

A control system is a network of subsystems and processes that turns an input into a desired output. Several parts work together in that network. The controlled variable is the quantity the system tries to regulate. The control signal is the command sent to change that variable.

Other key parts include the plant, the process, the system, disturbances, and feedback control. The plant is the physical thing being managed, such as a machine in a factory or the human heart. The process is the set of operations inside the plant that leads toward the goal. A disturbance is an outside factor that can push the output away from the target.

Feedback control helps the system stay on track. It checks the actual output against the reference input and makes real-time adjustments to reduce the difference. This self-correcting action helps keep the output consistent, even when disturbances occur.

An elevator is a clear example of this kind of system. When a passenger presses a button, that input is processed and the elevator moves to the requested floor. Engineers judge its performance by transient response and steady-state error. Transient response is the system’s reaction to a change, such as the elevator starting to move. Steady-state error is the difference between the actual and desired position after the system settles. Smooth motion and speed show how efficient and accurate the system is.

Understanding these parts helps control engineers design systems that are robust, efficient, and precise. That idea matters in healthcare, industrial automation, and many other fields. Control systems are a key part of modern technology.

Feedback in Everyday Control Systems

control systems

Control systems use feedback to keep a variable close to a desired value. They appear in both natural and engineered settings. Examples include blood sugar regulation, heart rate changes during stress, elevators, automated vehicles, aerospace systems, and automated manufacturing. A control system is a network of subsystems and processes that turns an input into a desired output. Several parts work together in that network. The controlled variable is the quantity the system tries to regulate.

control systems: applications

Control Systems in Cars and Furnaces

Control systems are used in cars, electric furnaces, and space shuttles to manage devices and processes. They help equipment work safely, correctly, and efficiently. Electrical engineering plays a central role in making these systems work in daily life. In modern vehicles, control systems help manage performance and safety. The steering wheel and accelerator are key inputs in the car control system. The steering direction and pedal pressure are processed to control the vehicle’s speed and...

open and closed-loop control systems

Feedback in Open and Closed Control Systems

Control systems are key parts of automation and engineering. They are usually grouped into open-loop and closed-loop systems. The difference depends on whether the output is fed back to the controller. An open-loop control system works without feedback from the output. It has two main parts: the controller and the controlled process. The controller receives an input signal and drives the process to reach the desired result. Because it does not check the output, the system does not correct...

effects of feedback

Feedback in Control Systems: Gain and Stability

Feedback in control systems changes gain, stability, and noise response. It does more than reduce error. A basic feedback system uses input, output, error, and feedback signals to shape how the system behaves. One major effect is on gain. Gain is the amount a system amplifies an input. Without feedback, the gain is changed by the factor 1 + GH, where G is the open-loop gain and H is the feedback factor. This means feedback can increase or reduce gain, depending on the frequency range. <br...

feedback control systems

Types of Feedback Control Systems

Feedback control systems can be grouped by how they behave, how their parameters change, and what kind of signals they use. These categories help engineers choose the right control method for a given system. They also make design and analysis easier. Linear feedback systems are theoretical models that simplify control design. In these systems, output is directly proportional to input within a certain range. An amplifier is a good example, but only while the input stays within its allowed range.

key terms and concepts

Explore how feedback control keeps elevators, vehicles, and body processes on target. Learn key parts like controlled variable, plant, disturbance, and error.

Feedback in Everyday Control Systems | JoVE K12

JoVE Core Electrical Engineering offers easy-to-understand animated videos that cover fundamental concepts of electric circuits along with circuit analysis techniques. It incorporates first-order and second-order circuits using operational amplifiers and circuit transformation concepts. The inclusion of practical design examples and real-world applications through scientist-in-action videos adds significant educational value, making complex concepts accessible.

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Feedback in Everyday Control Systems

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