What is Control theory: Definition and 70 Discussions
Control theory deals with the control of dynamical systems in engineered processes and machines. The objective is to develop a model or algorithm governing the application of system inputs to drive the system to a desired state, while minimizing any delay, overshoot, or steady-state error and ensuring a level of control stability; often with the aim to achieve a degree of optimality.
To do this, a controller with the requisite corrective behavior is required. This controller monitors the controlled process variable (PV), and compares it with the reference or set point (SP). The difference between actual and desired value of the process variable, called the error signal, or SP-PV error, is applied as feedback to generate a control action to bring the controlled process variable to the same value as the set point. Other aspects which are also studied are controllability and observability. This is the basis for the advanced type of automation that revolutionized manufacturing, aircraft, communications and other industries. This is feedback control, which involves taking measurements using a sensor and making calculated adjustments to keep the measured variable within a set range by means of a "final control element", such as a control valve.Extensive use is usually made of a diagrammatic style known as the block diagram. In it the transfer function, also known as the system function or network function, is a mathematical model of the relation between the input and output based on the differential equations describing the system.
Control theory dates from the 19th century, when the theoretical basis for the operation of governors was first described by James Clerk Maxwell. Control theory was further advanced by Edward Routh in 1874, Charles Sturm and in 1895, Adolf Hurwitz, who all contributed to the establishment of control stability criteria; and from 1922 onwards, the development of PID control theory by Nicolas Minorsky.
Although a major application of mathematical control theory is in control systems engineering, which deals with the design of process control systems for industry, other applications range far beyond this. As the general theory of feedback systems, control theory is useful wherever feedback occurs - thus control theory also has applications in life sciences, computer engineering, sociology and operation research.
Hey everyone. I'm hoping to get some advice from you guys. I am a senior studying Electrical Engineering. I am currently applying for graduate schools and for graduate fellowships (everything is mostly due mid-December). I plan to pursue a PhD. The only problem is, I'm not entirely sure which...
Good day to you people,
I have just started learning control theory at Uni, as part of my course, and I have to admit it is quite difficult to grasp.
I am starting from the basics, and I am having difficulty understanding what 's' is supposed to represent as regards the Laplace transform...
Hey folks wondering if anyone knows some good books on the following subjects...
Orbital transfers, specifically to Lagrange points with information on stable/unstable manifolds.
Control theory of satellites, new to control theory so perhaps I should be looking at a general control theory...
Homework Statement
So the first part of the problem asks us to solve for the state transition matrix, which I found to be:
Phi(t) = [2 0 0; (2-e^-t) e^-t 0; 0 0 e^-2t];
I need to find the matrix A, which I assume can be done with the following relation:
Phit(t) = e^(At)
where A is also a...
Most books I looked for Control Systems seem to be written by Electrical Engineers. Is there a good book which is written from the point of view of a Mechanical Engineers?
Hi all
I have majored in mechanical engineering and I have taken some basic control courses in the universities so I am wondering how to control the aileron on an air craft or fins on a rocket so as to get the path you want.
example : you want to change the air craft path to move up 10...
I am preparing for my control theory exam, but I have come across that I am struggling. I have a third order system and its asking to me determine when a value of an adjustable parameter, K for when the system is critically stable.
I just don't know what this corresponds two for a third order...
I looked at several books as well as internet sources, none of them explain how the controllability matrix is formed.
Given the linear time invariant system
x'(t)=Ax(t)+Bu(t)
A is an nxn matrix,
B is an nx1 matrix, (assuming single input)
Then controllability matrix R is given by...
I'm an engineering major, and my school has a lab that works on control theory. I think I would like to work on this in grad school, but I don't know if I have the background to look into it yet?
I found a free textbook on the subject from Rutgers...
Drone - grey, Asteroid - brown.
The goal is to steer the drone into the asteroid. The force acting upon the drone ("thrust") for movement can be in any direction, varies in magnitude, and can be applied at any discrete point in time.
The drone's future location is deterministic. I'm confused...
In most systems there is some sort of damping, but is it possible to develop a controller that works efficiently in a system with no damping? For example, imagine tracking the position of a linear cart moving on a track with no friction. Would it be possible to design a controller to supply a...
I have a zero at the origin of my root locus plot. I understand that I need integral control to have zero steady-state error. I have 2 questions about this.
1. When I add integral control like this, Kp (1/(Ti*s)) where Ti is from Z-N first method and Kp=1, I get a pole at the origin. I...
Homework Statement
Assume an under damped transient response graph, the graph will have the form of an envelope. My problem is that I need to find the open loop transfer function of my home build system (for a project) by using the open loop step response (which is an under damped response)...
This is an unusual question in this forum but I couldn't think of a better place.
I'm new to Signal Processing. Currently I'm looking into localization methods using multiple sensors. This requires, I assume, some sort of "controlling" matrix that will eventually approximate the location of...
Im trying to figure out how a certain example is working.
in this example the function
x = g - \frac{k}{m} \frac{(z-z0)^2}{(i-i0)^2}
where g, k, m, z0, i0 are fixed values and z, i are variables
The function above is written as
x = f(i,z) ( \sqrt{g} (z-z0) - y (i-i0) )
where f(i,z) is a...
In my control theory textbook, frequency response descriptions is one of three main areas of the subject (the others being Laplace transfer functions and state space representations).
My questions are: What is the purpose with frequency response in control theory? Why are not transfer...
I'm taking a course in control theory, and have been wondering for a while what the benefits are when you describe a system based on the Laplace method with transfer functions, compared to when you use the state space representation method. In particular, when using the Laplace method you are...
Hi, I'm an undergrad major in electrical engineering and physics; I am also minoring in mathematics. I am thinking of going into the field of control theory. I was wondering what branches of mathematics are particularly relevant to the field of control theory (I had a mathematics professor who...