Name: cruise control and aircraft system models
Uploaded: 2024-11-21T14:54:07.000Z
Duration: 1 min 22 s
Channel: JoVE

汽车中的巡航控制系统是一种多输入系统，可根据驾驶员设定的速度偏好进行调节，并补偿上坡等干扰因素。
该系统的框图将期望速度和扰动作为输入。
当扰动被消除时，框图简化为特定的传递函数。当主输入信号被消除时，框图则得到另一个传递函数。
系统的总体响应是扰动信号和输入信号所引起响应的总和。
飞机是一个多变量系统，具有多个输入和输出，例如飞行控制装置和飞机的运动。
框图可以表示每个输入和输出，而简化版本则使用向量来代表多个输入和输出。
这些系统也可以用反馈来表示，其中系统各部分之间的关系以矩阵形式表达。
通过求解这些方程，闭环传递矩阵给出了输出与输入之间的最终关系。
考虑传递函数的特定矩阵。代入后，可计算出闭环传递函数矩阵。

多输入多变量系统

Multi-input and Multi-variable systems

汽车中的巡航控制系统设计为多输入系统，用于保持驾驶员的期望速度，同时补偿地形变化等外部干扰。巡航控制系统的框图通常包括两个主要输入:驾驶员设定的期望速度和任何外部干扰，例如道路的坡度。通过调节发动机油门，系统将车辆的速度保持在尽可能接近期望值。

在没有干扰的情况下，巡航控制系统的框图可以简化为一个特定的传递函数。这个传递函数表示期望速度输入和车辆实际速度之间的关系。

<img alt="Equation1" src="/files/ftp_upload/16107/16107_PT_equation_001.svg" style="height: 36px;">

其中T_d(s)是从期望速度R(s)到实际速度Y(s)的传递函数。

相反，当主要输入信号（所需速度）无效时，框图简化为另一个传递函数，仅表示系统对外部干扰的响应。

<img alt="Equation2" src="/files/ftp_upload/16107/16107_PT_equation_002.svg" style="height: 52px;">

其中T_u(s)是从扰动D(s)到实际速度Y(s)的传递函数。

巡航控制系统的整体响应是对期望速度和干扰输入的响应的叠加。这可以用数学表示为:

<img alt="Equation3" src="/files/ftp_upload/16107/16107_PT_equation_003.svg" style="height: 30px;">
该叠加原理说明了系统如何调整以保持所需速度同时抵消干扰。

在更复杂的系统（如飞机）中，必须考虑多个输入和输出。输入可能包括来自飞行员的控制信号，例如副翼、方向舵和升降舵的调节，而输出则是飞机的响应，例如滚转、俯仰和偏航的变化。这种系统的复杂性使得必须使用矢量和矩阵来简洁地表示多个输入和输出。

飞机等多变量系统的框图可以使用矢量表示法来简化。输入和输出以矢量表示，它们的关系以传递矩阵表示。这些系统中的反馈回路也可以使用矩阵方程来描述，从而全面表示系统的动态。

汽车中的巡航控制系统是一种多输入系统，可根据驾驶员设定的速度偏好进行调节，并补偿上坡等干扰因素。  
...的框图

Education

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JoVE Core

Electrical Engineering

电气工程

Unit 1

第一单元

Diagrams and Signal Flow Graphs

图表与信号流图

KEY TERMS AND CONCEPTS

关键术语与概念

cruise control and aircraft system models

Cruise control systems show how a control system can handle more than one input. In a car, the driver sets a desired speed, and the system also responds to outside disturbances such as changes in road slope. The throttle is adjusted so the vehicle speed stays as close as possible to the target value.

When the disturbance is ignored, the cruise control block diagram can be reduced to a transfer function. This transfer function describes how the desired speed input, R(s), affects the actual speed output, Y(s). When the desired speed signal is set to zero, the diagram can be reduced in a different way. That case gives the transfer function for the disturbance input, D(s), to the vehicle speed, Y(s).

The full system response comes from adding these two responses together. This is the principle of superposition. It shows how the cruise control system works to track the driver’s setting while also reducing the effect of disturbances.

More complex systems, such as airplanes, have multiple inputs and outputs. The pilot may change the aileron, rudder, and elevator, and the aircraft responds with roll, pitch, and yaw. Because there are several signals on both sides, vectors and matrices are used to write the system in a compact form.

In these multi-variable systems, inputs and outputs are grouped into vectors. Their relationships are described with a transfer matrix. Feedback loops can also be written with matrix equations. This gives a complete way to represent how the system behaves.

Cruise Control and Aircraft System Models

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Block Diagrams in Control Systems

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multi-input and multi-variable systems

Cruise control systems show how a control system can handle more than one input. In a car, the driver sets a desired speed, and the system also responds to outside disturbances such as changes in road slope. The throttle is adjusted so the vehicle speed stays as close as possible to the target value. When the disturbance is ignored, the cruise control block diagram can be reduced to a transfer function. This transfer function describes how the desired speed input, R(s), affects the actual...

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Mason’s Rule in Signal Flow Graphs

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key terms and concepts

Learn how cruise control uses multiple inputs, transfer functions, and superposition, and how airplanes use vectors and matrices to model roll, pitch, and yaw.

Cruise Control and Aircraft System Models | 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.

electrical engineering

Cruise Control and Aircraft System Models

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