A system that may be electronic circuits or even software that uses control theory (principally differential equations) to control an output by monitoring various aspects of the system under control and varying inputs all towards meeting a defined goal. Some famous examples are controlling a ...

learn more… | top users | synonyms

2
votes
1answer
47 views

Effect of zeroes in system stability

Suppose we have two third order systems (a and b), with three poles and two zeroes,poles for both the systems are at the same positions in frequency domain but these systems differ in the placement of ...
-1
votes
0answers
21 views

Developing System with wireless, flash drive and power harvesting units [closed]

I need a development system which supports wireless or Bluetooth and has flash drive. Be as small as possible and tolerate very low and high temperature. Better if it has some supporting units for ...
1
vote
1answer
89 views

How to represent circuit in state space

I have this circuit and I must represent it in state space. I know the process because I have done similar ones but having trouble with this one. I have found the Kirchhoff equations for the 2 loops ...
1
vote
1answer
54 views

What is the difference between disturbance and noise for dynamic systems?

In most references from dynamic system theory, the following linear continuous dynamic system is considered. $$\frac{\text{d}x(t)}{\text{d}t}=Ax(t)+Bu(t)+Dd_{1}(t)\quad (1)$$ $$y(t)=Cx(t)+Ed_{2}(t) ...
1
vote
1answer
62 views

How to determine the transfer function of a system including disturbances

I'm trying to determine the open-loop transfer function of the system below (in order to determine PID gains). If I account for the disturbance \$(9.81*6700)\$ in the system and use equation 2, I ...
-2
votes
0answers
21 views

control circuit of humanoid robot: is it worth to learn and use ROS

i am building the upper body of a humanoid robot for my MSc thesis project with 24 dc motors and multiple sensors(something like i-cub or Nao) i have basic knowledge of communication protocols and ...
1
vote
2answers
55 views

What is the correct transfer function of a feedback loop if the summing amplifier has different input resistors?

Suppose I have a circuit below: simulate this circuit – Schematic created using CircuitLab I know the the transfer function of a negative feedback loop is: ...
0
votes
1answer
132 views

Using a transistor as a heater

I have the task to build and control 35 heaters, 10 W each. I first thought about using power resistors (like in this datasheet) as heating devices, but they'd need high currents in order to get the ...
1
vote
1answer
60 views

How to find the state-variable equations from the signal flow graph of the system?

How to find the state-variable equations, i.e, the state equation & the output equation for the system described by the signal flow graph below?
2
votes
1answer
51 views

General form of a Transfer Function

A professor is writing the general form of a Transfer Function as: $$k\cdot s^{l}\cdot \frac{\prod\limits_{i=1}^{m}(1+\frac{s}{z_{i}})}{\prod\limits_{i=1}^{n}(1+\frac{s}{p_{i}})}$$ but in every book ...
0
votes
1answer
52 views

Powering circuit with alternative and/or concurrent power sources

I have one of these led projectors which is normally powered by the embedded motion sensor. I want to be able to power it manually by a switch button. I need to do this in both alternative and ...
0
votes
0answers
36 views

How to implement a multiple controller system?

I want to make a system that switches between multiple controllers depending on a parameter 'x' in the system. Eg. If there is no noise use a pid controller. If there is noise use a resonant ...
0
votes
1answer
63 views

Desired response of PI controller in motor vector controller

In vector control (field-oriented control) of motors (specifically induction motors), a rotating reference frame is attached to the rotor flux to give "DC" values in the current controller. This ...
0
votes
0answers
85 views

Finding transfer function of this signal flow graph using Mason's Rule

In the following signal flow graph, how do you find the transfer function Vload(s)/Idist(s) using Mason's rule? The solutions manual says it would be the same transfer function as if you were finding ...
1
vote
4answers
170 views

Why is the frequency complex

When we take the Laplace transform of a function, why is the frequency (s) complex? I can not understand the significance of complex frequency. Please help or give some references.
-1
votes
1answer
172 views

Need suggestions on control system engineering [closed]

I am sophomore studying control systems and the problems given in the books( like Norman Nise ) look too easy. Please suggest some good book with really good problems.
0
votes
2answers
76 views

How do I hold a signal high from one high pulse?

Assuming I send a signal wirelessly to a receiver connected to a fan. if the receiver detects that a pulse is there, it switches on the fan. the fan should stay on until it detects another high pulse, ...
0
votes
2answers
403 views

How to calculate Kp, Kd and Ki?

The motor operates within 140 rev/min to 600 rev/min. The controller gives an output in the range 4 to 20 mA. The sensor output reading equivalent to 400 rev/min, actual reading was 404 rev/min. The ...
0
votes
1answer
76 views

Relationship between switching frequency and controller's crossover frequency in buck SMPS

Context: tuning the control loop of a buck SMPS. I specicifally have a TI TPS40200-based circuit in mind, but I think this applies to SMPS design in general. Quoting from Type 2 compensation network: ...
0
votes
2answers
497 views

Cascading PID DC Motor Position & Velocity Controllers

I'm trying to build a robot with a differential drive powered by two DC motors. First I implemented a PID Controller to control the velocity of each motor independently. Estimated the TF using the ...
1
vote
1answer
229 views

SMPS : Average Current Control Vs Peak Current Control

Please correct my understanding. I understand that in peak current control mode, the slow outer voltage control loop generates a current command to the faster inner current loop. This current command ...
-2
votes
2answers
62 views

Model and Control of a Physical System [closed]

Suppose i have a physical system (set of interacting elements ) that i want to control. Best thing we can do to understand this physical system and hence control it, is to model it. We ...
1
vote
5answers
182 views

Kinds of Feedback

"Feedback is a process in which information about the past or the present influences the same phenomenon in the present or future" I find the idea of feedback quite fascinating and i could ...
1
vote
2answers
211 views

Time domain and Frequency domain

what is the difference between time domain and frequency domain components? How do these domains differ from each other?
5
votes
5answers
500 views

Control theory basics

I'm trying to understand something very basic about Control Theory. Let's say I have the following loop: If we'll relate this loop to a cart with a motor going in its single axis from X = 0 to X = ...
2
votes
1answer
66 views

When the Gain Margin is negative, for what range of frequencies is will the output resonate out of control?

If your system/transfer function has greater than zero gain for the frequency associated with -180 degrees phase, the system is said to be unstable. What does this mean for other input frequencies? ...
4
votes
1answer
140 views

Practical Limit of Feedback Control Systems WRT Bandwidth

In a digital feedback control system, I'm interested in the practical limit of what the correctable bandwidth is. For example, given a very simple system: A sensor can sample a simple X position ...
-1
votes
1answer
96 views

Digital Control Engineering book recommendations [closed]

What are good books on digital control engineering specifically? I'm a third year electrical/computer engineering student who will be doing a course on digital control next semester, but would like to ...
0
votes
3answers
104 views

Step response to feedback loop with disturbance

When using step response to a feedback loop with disturbance. Why do we analyze the step response of the disturbance D and the step response of the input R separately. Instead of considering them ...
0
votes
0answers
52 views

Nyquist VS Nichols plot

Which is the most commonly used: Nyquist or Nichols plot? Do they have their own particular use or is it just a matter of preference?
0
votes
0answers
39 views

Detect unathorized access in RFID security system

I have a question about RFID security system and tags when implemented in traffic monitoring system. The scenario is a 1) Reader and a 2) barricade which is some 2 meters ahead of reader. Now how do ...
0
votes
2answers
44 views

Is there any correlation between eigen functions and eigen vectors of an LTI system?

Eigen functions are the origin for Laplace transform while eigen vectors is for state space representation.Can we relate the eigen concept in these two? The complex exponential functions, are eigen ...
-1
votes
2answers
54 views

Controlling LEDs with multiple controllers [closed]

I have three black boxes each controlling an LED output. Each black box takes an input voltage and provides an output voltage (ranging from 0-12V) to illuminate the LED. Is it possible to alternate ...
1
vote
1answer
206 views

Switched Mode Power Supply : Voltage Mode Control and Error Amplifier Output

I am trying to understand how regulation happens on Cycle-Cycle basis in the case of Voltage Mode Control (VMC) and Current Mode Control (CMC). I understand that in the case of VMC, an error ...
1
vote
1answer
108 views

transfer function and error gain function

simulate this circuit – Schematic created using CircuitLab I know the difference between those two functions , but i want to see the relation between them , i think that the error gain ...
1
vote
1answer
283 views

PID gains from the transfer function of a plant

I am trying to calculate gains ( Kp, Ki, Kd ) of a PID controller. I have to improve the response of a plant. I already have the Transfer function of the plant. I was wondering if matlab has some ...
2
votes
2answers
142 views

Does the use of PID controller require knowledge of plant's Transfer Function

As simple as that. I assume that you use PID when you do not know the Transfer Function of the system, otherwise you use it and plug it directly in the closed-loop control.
0
votes
2answers
111 views

Overshoot control

Suppose I have the following step response: $$y_{step}(t)=\frac{kP}{1+kP}(1-e^{\frac{-t}{\tau}})$$ where k is constant and P is the plant. How may I determine the values of k for which there would be ...
0
votes
1answer
51 views

Can you implement a control algorithm and send the inputs via xbee?

I know this question is little bit vague, but let's say that I have a robot or a quadrotor to control. I want to implement the control algorithm (PID, robust, or LQR) in the PC not in the robot/quad, ...
1
vote
1answer
303 views

Astrom-Hagglund Relay PID tuning - relay transfer function?

I'm implementing a PID temperature controller on a PLC. To cut down on installation time (this design may be reused many times), I want to have the PID parameters tuned automatically rather than ...
3
votes
5answers
158 views

System response types

Whenever I am given a system type with a certain transfer function, I am always asked to proceed to find out the 1. impulse response and 2. step response of the system. My question is, what is so ...
0
votes
2answers
101 views

Control and transfer functions

I would like to determine the following transfer functions: $$T_1=\frac{y^\wedge}{d^\wedge}$$ $$T_2=\frac{y^\wedge}{r^\wedge}$$ $$T_3=\frac{e^\wedge}{d^\wedge}$$ $$T_4=\frac{e^\wedge}{r^\wedge}$$ In ...
2
votes
1answer
185 views

Interfacing Matlab with a NI real time target (cRIO 9073)

I currently have a control system implemented in Matlab that controls a vehicle. The tracking is performed using an overhead camera, and commands are sent to the vehicle via xbee. I have now added a ...
2
votes
1answer
251 views

Proportional controller

Sirs, I am not able to understand why Proportional controller introduces offset.Please consider follwing paragraph I found on internet, credit to ** http://blog.opticontrols.com/archives/344 **, ...
2
votes
1answer
114 views

When is a programmable logical controller the best choice? [duplicate]

I am studying PLCs as a part of my Elements of Industrial Automation class. Trouble is, I can't imagine why would anyone use such a thing. For complex tasks, microcontrollers are available. The vast ...
3
votes
2answers
139 views

Pole-zero cancellation Paradox

Suppose we have an open-loop transfer function $$G(s) = \frac{1}{s(s+a)(s+b)}$$ If we plot the root locus for the closed-loop system we will get roughly something like this : Now the question is ...
1
vote
3answers
112 views

How can we find transfer function of this n/w

How can we find the transfer function $$\frac{E_0(s)}{E_1(s)}$$ of this RC network simulate this circuit – Schematic created using CircuitLab
1
vote
0answers
112 views

PD control (PID without I) - Homework help

I've been given a system - x" = bx′ + kx + ru and I've been asked to rewrite it in the canonical form x' = AX + BU. I've got -- ...
0
votes
0answers
67 views

What is remnant in control engineering?

Is the term of "remnant" still being used in modern control theory? If yes, what is different between remnant spectrum and output spectrum?
1
vote
1answer
64 views

Linearity and time invariance

If the input of an unknown system is shown by: \$x(t)= u(t)-u(t-1)\$ which results in the following output: \$y(t)=u(t)-u(t-3/2)\$ then what can be said about the linearity and time invariance of ...