Control Systems: Principles and Applications in Mechanical Engineering

Question 1

Which of the following is NOT a type of feedback control system?

Accepted Answer

Open-loop control

Answer

Negative feedback

Answer

Positive feedback

Answer

Proportional-integral-derivative (PID) control

Question 2

What is the primary purpose of a feedback loop in a control system?

Accepted Answer

To measure the output and compare it to the reference signal

Answer

To provide a reference signal for comparison

Answer

To amplify the error signal

Answer

To control the actuator

Question 3

What is the purpose of a PID controller?

Accepted Answer

To provide proportional, integral, and derivative control actions

Answer

To compensate for system nonlinearities

Answer

To reduce overshoot in the system response

Answer

To increase the system's bandwidth

Question 4

The primary purpose of a PID controller is to:

Accepted Answer

Reduce steady-state error

Answer

Improve transient response

Answer

Increase system stability

Answer

Respond quickly to input changes

Question 5

The range of frequencies over which a system has a gain of at least -3 dB is known as the:

Accepted Answer

Bandwidth

Answer

Cutoff frequency

Answer

Resonant frequency

Answer

Nyquist frequency

Question 6

Which of the following is an example of a nonlinear control system?

Accepted Answer

Fuzzy logic control

Answer

PIC control

Answer

State feedback control

Answer

Proportional control

Question 7

A controller that uses a mathematical model of the plant to predict its behavior is known as a:

Accepted Answer

Model-predictive controller

Answer

Feedforward controller

Answer

Feedback controller

Answer

PID controller

Question 8

In the field of engineering, which of the following is NOT an application of control systems?

Accepted Answer

Project management

Answer

Robotics

Answer

Automotive engineering

Question 9

Identify the component that is not part of a feedback control system:

Accepted Answer

Disturbance

Answer

Sensor

Answer

Controller

Answer

Actuator

Question 10

What is the primary function of a proportional controller?

Accepted Answer

Minimize the deviation between the measured and desired output

Answer

Completely eliminate the error over time

Answer

Amplify the error signal significantly

Answer

Generate a control signal influenced by the error's derivative

Question 11

Which type of feedback system is widely used in various applications?

Accepted Answer

Negative feedback

Answer

Positive feedback

Answer

Cascaded feedback

Answer

Open-loop control

Question 12

What is a defining characteristic of a PID controller?

Accepted Answer

It combines proportional, integral, and derivative control actions

Answer

It features an exceptionally high gain

Answer

It is exclusively used in open-loop control systems

Answer

It can only be applied to nonlinear systems

Question 13

A control system with a high damping ratio typically exhibits:

Accepted Answer

Extended settling time

Answer

Rapid response to changes

Answer

Significant overshoot

Answer

Instability

Question 14

Which feedback type enhances system stability and reduces overshoot in a control system?

Accepted Answer

Negative feedback

Answer

Positive feedback

Answer

Proportional feedback

Answer

Derivative feedback

Question 15

Determine the Laplace transform of the function f(t) = e^(-at):

Accepted Answer

1/(s+a)

Answer

a/(s+a)

Answer

1/(s-a)

Answer

a/(s-a)

Question 16

Identify the stability criterion for a control system:

Accepted Answer

Poles in the left-half plane

Answer

Poles in the right-half plane

Answer

Poles on the imaginary axis

Answer

Poles at the origin

Question 17

Distinguish between a type 0 and a type 1 control system:

Accepted Answer

Type 0: No steady-state error, Type 1: Steady-state error

Answer

Type 1: No steady-state error, Type 0: Steady-state error

Answer

Type 0: More stable, Type 1: Less stable

Answer

Type 1: More stable, Type 0: Less stable

Question 18

What is the primary function of a Kalman filter?

Accepted Answer

State estimation from noisy measurements

Answer

Control using a state-space model

Answer

Controller design

Answer

System stability analysis

Question 19

In control systems, which fundamental concept involves comparing the output signal to a reference signal and using the difference to adjust the system's behavior?

Accepted Answer

Feedback

Answer

Open-loop control

Answer

Linearity

Answer

Stability

Question 20

In a closed-loop control system, what happens to the output signal?

Accepted Answer

It is compared to the reference signal to generate the control signal

Answer

It is unaffected by external disturbances

Answer

It is always equal to the reference signal

Answer

It is fed forward to the controller

Question 21

Which of the following is a type of controller commonly used in mechanical engineering applications?

Accepted Answer

PID controller

Answer

State-space controller

Answer

Fuzzy logic controller

Answer

Neural network controller

Question 22

Which of the following techniques can be used to enhance the performance of a control system?

Accepted Answer

Adding a compensator

Answer

Increasing the gain

Answer

Decreasing the damping ratio

Answer

Reducing the time constant

Question 23

A control system is considered linear if:

Accepted Answer

Its output is proportional to its input

Answer

Its gain is constant

Answer

It has no time delay

Answer

It is stable

Question 24

In a control system designed to regulate the temperature of a furnace, what is the controlled variable?

Accepted Answer

Temperature of the furnace

Answer

Heat input to the furnace

Answer

Airflow rate into the furnace

Answer

Fuel consumption

Question 25

What is the fundamental principle of state-space analysis?

Accepted Answer

State-space analysis represents a system's dynamic behavior using differential equations.

Answer

State-space analysis directly determines a system's stability based on its poles and zeros.

Answer

State-space analysis can predict a system's response to any input.

Question 26

Which of the following is NOT an essential component of a basic control system?

Accepted Answer

Reference signal

Answer

Sensor

Answer

Actuator

Answer

Controller

Question 27

What is the primary purpose of negative feedback in a control system?

Accepted Answer

To reduce the difference between the actual output and the desired output

Answer

To amplify the system's response

Answer

To introduce instability

Answer

To increase the system's sensitivity

Question 28

Which type of control system can automatically correct errors without relying on a reference signal?

Accepted Answer

Closed-loop control

Answer

Open-loop control

Answer

Proportional control

Answer

Integral control

Question 29

Which Nyquist stability criterion states that the number of encirclements of the (-1,0) point must be odd for a system to be stable?

Accepted Answer

encirclement criterion

Answer

Right-half plane zero criterion

Answer

gain margin criterion

Answer

phase margin criterion

Question 30

What is the transfer function of a system where the input is voltage and the output is current?

Accepted Answer

1/s

Answer

s^2

Answer

1/s^2

Answer

s

Question 31

What is the key distinction between a PI and a PID controller?

Accepted Answer

PI controllers have a proportional and integral term, while PID controllers additionally incorporate a derivative term.

Answer

PID controllers have a proportional and derivative term, while PI controllers additionally incorporate an integral term.

Answer

PI controllers have no derivative term, while PID controllers have a negative derivative term.

Answer

PID controllers have no integral term, while PI controllers have a positive integral term.

Question 32

Which method is commonly employed to linearize a nonlinear system?

Accepted Answer

Taylor series expansion

Answer

Perturbation analysis

Answer

Numerical simulation

Answer

Graphical analysis

Question 33

What is the function of a supervisory control system within a hierarchical control system architecture?

Accepted Answer

To oversee and intervene in the operation of the controlled process

Answer

To directly control the process in real-time

Answer

To provide a user interface for the operator

Answer

To implement safety functions

Question 34

Which characteristic is essential to a feedback control system?

Accepted Answer

It measures the output and adjusts its action accordingly.

Answer

It is inherently stable.

Answer

It operates without an external energy source.

Question 35

What is the primary function of a proportional controller?

Accepted Answer

To generate a control signal proportional to the error.

Answer

To induce oscillations around the setpoint.

Answer

To eliminate the error entirely.

Question 36

Which control method is most appropriate for systems experiencing significant load variations?

Accepted Answer

Proportional-Integral-Derivative (PID) control

Answer

Integral control

Answer

Proportional control

Question 37

What is the key advantage of employing a closed-loop control system?

Accepted Answer

It corrects for disturbances and maintains the desired output value.

Answer

It is inherently more efficient than an open-loop system.

Answer

It is less expensive to implement.

Question 38

Which of the following is NOT considered a limitation of feedback control systems?

Accepted Answer

They are universally applicable to all system types.

Answer

They can introduce delays and oscillations.

Answer

They may require complex hardware and software.

Answer

They are susceptible to noise and disturbances.

Question 39

What mathematical representation captures the transfer function of a first-order system?

Accepted Answer

G(s) = K / (s + a)

Answer

G(s) = K / s

Answer

G(s) = K * (s + a)

Answer

G(s) = a / s

Question 40

What concept in control systems describes the frequency range over which the system responds to inputs?

Accepted Answer

Bandwidth

Answer

Maximum output amplitude

Answer

Rise time

Question 41

What is the primary objective of system identification in control engineering?

Accepted Answer

To develop a mathematical model of a system based on experimental data.

Answer

To analyze system stability.

Answer

To design the system's controller.