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 ...

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44 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 ...
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53 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 ...
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76 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.
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79 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 ...
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1answer
34 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, ...
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1answer
63 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 ...
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5answers
113 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 ...
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2answers
83 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 ...
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1answer
40 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 ...
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1answer
103 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 **, ...
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1answer
68 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 ...
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2answers
108 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 ...
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3answers
62 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
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0answers
77 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 -- ...
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0answers
58 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?
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1answer
50 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 ...
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1answer
95 views

Derive transfer function from block diagram

I have this block diagram which I already reduced pretty much: Now I want to derive the transfer function from phi_o1 to q. ...
2
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1answer
124 views

Difference between online PID and offline PID tuning?

I've been reading about PID control on the internet lately (Wikipedia). I came across the words 'online' and 'offline' in PID tuning. I googled it but couldn't find anything. What does this mean in ...
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1answer
39 views

how to make a system respond to IR laser? [closed]

Lets say i have 2 separate systems called Box A and Box B. Box A has an IR laser beam attached to it. What equipment can i use to make Box A make a certain action ONLY when the IR laser attached to ...
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0answers
62 views

How to deal with unstable pole?

I'm trying to use PD control to keep an inverted pendulum centered, by attractive electromagnets mounted as a radial magnetic bearing. The control is cascaded into an inner current control loop and an ...
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0answers
25 views

How to use rank 1 covariance matrix for designing a kalman filter

I was trying to estimate the covariance matrix of the measurement noise of a (simulated) MIMO system. Turns out. In matlab cov(data) gives me a rank 1 matrix. I checked it. And I noticed that all ...
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1answer
90 views

Affine Non Autonomous State Space system

Normally We all know the state space model of the the form der(x) = F*x(t)+G*u(t) y = H*x(t)+J*u(t). However I came across a state space model which has the following form der(x) = F*x(t)+G*u(t) + ...
3
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2answers
281 views

Open loop vs closed loop in control theory

I have two questions: Why we study stability in open loop rather than closed loop (which is the system that will be implemented). and is there a relation between response time in closed loop & ...
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3answers
99 views

Control System - Changing damping on-the-fly?

I'm trying to implement a PID algorithm on a microcontroller that controls an actuator with a hard physical limit. In MATLAB, there's no consequence to large overshoots/hitting saturation at high ...
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1answer
56 views

Is SSB (Single Sideband) linear, why? [closed]

How to derive it? I have been confused about this for a long time.
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3answers
242 views

Describing step response in terms of poles and zeros of transfer function?

me and a friend are stuck describing something, we're both coming to terms with using matlab and we're trying to understand the design of a simple control system for controlling the steady-state error ...
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1answer
69 views

Exclusive control over actuators

I feel kind of stupid asking this question, but after unsuccessfully searching for papers and then starting to draw my own solution with a lot of XORs to the following problem, I started wondering ...
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2answers
96 views

External programing of an mcu without Hex

We need to change a controller code from the out side as they do with industrial MCU. So that you have an MCU, with a program on it, and someone can program some "words" to it, that will determine how ...
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2answers
151 views

How should sampling frequency, switching frequency, control loop update frequency, and anti-aliasing filter corner frequency relate?

Suppose one is designing a processor-controlled switching supply. In general, how does one properly select switching frequency vs. control loop update frequency vs. feedback sampling frequency vs. ...
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1answer
97 views

Is impulse response always differentiation of unit step response of a system?

I was trying to solve a question in which the transfer function of a system was asked, its unit step response being given: $$ c(t) = 1 - 10^{-t} $$ The method that the book followed was to first ...
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3answers
295 views

What should be DC gain of the system?

Step response of system is \$c(t) = 5 - 0.5e^{-2t} + 8e^{-t}\$ then find steady state gain. Answer is -7.5 Now in book solution is given as : Since this is step response we will find impulse ...
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3answers
393 views

How does control theory apply to my real-world processor-controlled boost converter?

I have a limited understanding of control theory. I dealt with poles and zeroes and transfer functions in school. I've implemented several microprocessor-based control schemes for DC/DC converters. ...
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2answers
2k views

What is a “dry contact input”?

I'm a PC software guy, a newbie to electronics. Recently, I've got a project in which I need to source for a DAQ that can provide dry contact inputs to an interfacing digital output controller. The ...
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85 views

Frequency Inverter LS IS5

I have been working with a IS5 frequency inverter. I'm trying to use the Sensorless Torque control, for a Wind Turbine Emulator, via an external reference. The issue is, when I turn the inverter on ...
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1answer
93 views

Signal flow simplification

I've looked at the various simplifications that can be made for signal flaw diagrams to combine branches; however, I can't work out how one can apply a transformation to simplify the following ...
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2answers
200 views

Can you control a 12V Solenoid Valve using motor dev kit MCLV-2?

The MCLV-2 is a motor driver development board, of 24 volt and up to 15Amp (in total). Aside driving a motor, I'm also interested in testing to see if these circuitries are suitable to run a 12 volt ...
3
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3answers
2k views

Undamped natural frequency

What's the definition of the undamped natural frequency? I've looked and I cannot find it. A second order system has the following transfer function $$ H(s) = \frac{A_o \omega_n^2}{s^2 + 2 \zeta ...
3
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1answer
668 views

What are the major advantages of using a closed-loop over an open-loop and vice versa?

I'm trying to gain a better understanding on the pros and cons using closed-loop or open-loop motor control. Also trying to better learn when it's more sensible to apply each one
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4answers
617 views

Conditional stability

I'm learning about op-amps and feedback and how feedback affects their stability. I've been reading about gain and phase margin and their uses when I came across this: I don't quite understand ...
4
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1answer
159 views

PID controller, tuning and creation

I have been having some good success with my first PID controller. It seems it needs just a little bit more work. Below is a picture of a sample run with my controller implemented. Currently I only ...
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2answers
218 views

Does gain affect stability of a Transfer Function?

I have a control system that we are working on with a forward transfer function of:- \$ \dfrac{K(2s+3)}{s^2(s^4+2s^3+4s^2+2s+7)}\$ So I've set up the routh table for this, I've found there are 2 ...
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1answer
629 views

The open loop transfer function of a unity feedback control system is given as \$G(s) = \frac{as+1}{s^2}\$

The open loop transfer function of a unity feedback control system is given as \$G(s) = \frac{as+1}{s^2}\$. What value of 'a' will give a phase margin of 45° ? \$G(s) = \frac{as+1}{s^2}\$ ...
1
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1answer
328 views

Rise time for second order RC filter?

Can somebody help me in deriving the expression for rise-time for second order RC filter. simulate this circuit – Schematic created using CircuitLab
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3answers
178 views

I need help Building A Solid state Electro magnetic Mixer

I'm just getting into electronics, and I would like to build an electromagnetic mixer. See here. Most of the tutorials I have found have magnets stuck to a motor spinning under a non magnetic material ...
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2answers
107 views

Determining whether a system is LTI given response to a rectangle box input

Given a system, it is possible to determine whether the system is LTI given the response to input to the system, other than the unit impulse? Specifically, my input to the system is ...
4
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2answers
73 views

Definition of a System

A mathematical operator is generaly a mapping between a domain set of functions and a range set of functions.One example is the derivative operator L ( L[f] = f' ) for example. Can i say every ...
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0answers
48 views

Impulse & Frequency Response Help

Suppose that 2 systems are connected in cascade; i.e., the output of S1 is the input to S2. The 2 systems are specified as follows: S1: y1[n] = x1[n] + x1[n-1] + x1[n-2] S2: y2[n] = x2[n] + x2[n-1] ...
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1answer
435 views

bldc motor torque controller

I have a working custom motor controller for three phase sensorless bldc motors. I've implemented open loop speed control, where the duty cycle is changed to change speed. I've also implemented a ...
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1answer
65 views

LTI Response Help

A system is known to be LTI. The response of the system to a step function u[n] is δ[n] + δ[n-1]. a.) Find the response of the system to 2u[n] + u[n-1] b.) Find the response to the unit impulse ...
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3answers
236 views

Variable liquid flow rate control

I'm not an Engineer by trade, rather a programmer looking to put together a micro controller project that alters the water flow rate of a cooling system to maintain a specific operating temperature ...