4.1.1 - Open and Closed Loop Systems

What are the three basic elements of a system?

• Input, Process, Output

• Input, Controller, Feedback

• Input, Feedback, Output

• Controller, Process, Output

Answer explanation

The three basic elements of a system are Input, Process, and Output. Input refers to the data or resources entering the system, Process involves the transformation of that input, and Output is the result produced by the system.

What is the role of a controller in a control system?

• To generate a control signal

• To provide feedback

• To process the output

• To act as an input

Answer explanation

The controller's primary role in a control system is to generate a control signal that directs the system's behavior. This signal is essential for achieving the desired output based on the system's input and feedback.

Which of the following is a type of mathematical model used in control systems?

• Differential equation model

• Algebraic model

• Geometric model

• Statistical model

Answer explanation

The differential equation model is a fundamental type of mathematical model in control systems, as it describes the relationship between system inputs and outputs through differential equations, capturing dynamic behavior effectively.

What is an open loop control system also known as?

• Automatic control system

• Feedback control system

• Error control system

• Manual control system

Answer explanation

An open loop control system is also known as a manual control system because it operates without feedback, relying on human intervention to adjust the output, unlike automatic or feedback systems that self-regulate.

In a closed loop control system, what is the error signal?

• The difference between input and feedback signal

• The sum of input and output

• The product of input and feedback signal

• The difference between input and output

Answer explanation

In a closed loop control system, the error signal is defined as the difference between the input and the feedback signal. This helps in adjusting the system to minimize the error and achieve the desired output.

What is the main characteristic of an open loop control system?

• No feedback from output

• Feedback from output

• Automatic adjustment

• Error detection

Answer explanation

An open loop control system operates without feedback from the output. It executes commands based solely on input, lacking the ability to adjust or correct errors based on the output, which distinguishes it from closed loop systems.

Which of the following is an example of a closed loop control system?

• Thermostat without feedback

• Manual light switch

• Digital camera taking a photograph

• Water level maintenance in a storage tank

Answer explanation

The water level maintenance in a storage tank is a closed loop control system because it continuously monitors the water level and adjusts the inflow or outflow to maintain the desired level, using feedback to make corrections.

What is the purpose of a mathematical model in a control system?

• To analyze and design control systems

• To provide physical structure

• To generate power

• To act as a controller

Answer explanation

The purpose of a mathematical model in a control system is primarily to analyze and design control systems. It helps in understanding system behavior and developing effective control strategies.

What is the main difference between open loop and closed loop control systems?

• Type of output

• Complexity of process

• Type of input

• Feedback presence

Answer explanation

The main difference between open loop and closed loop control systems is the presence of feedback. Closed loop systems use feedback to adjust their output based on the desired outcome, while open loop systems do not.

What does a closed loop control system automatically adjust?

• Output to match the desired level

• Input to match the output

• Process to match the input

• Feedback to match the error signal

Answer explanation

A closed loop control system automatically adjusts the output to match the desired level by using feedback to minimize the difference between the actual output and the target value.