Questions tagged [control-engineering]
Questions about the models and theories of control engineering and the application of control theory to design systems with desired behaviors.
374
questions
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16 views
What is the mathematical basis for the Ziegler-Nichols method for tuning a PID loop?
The Ziegler-Nichols method of tuning PID control loops has been around since the 1940's, and has been widely applied in many areas of engineering. I understand that it is really only a heuristic ...
0
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1answer
19 views
Transfer function for a quadcopter with linear velocity inputs
I found the control for a quadcopter using the angular velocities or thrust power as the input, but I need a model where I can set the initial and final position (for example, from (0,0,1) to (0,1,1))....
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0answers
18 views
Python control module initial condition response
In python control module in initial condition response I am confused by what is meant here by initial condition. Because both state space object and transfer function object can be entered. For state ...
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0answers
47 views
The optical encoder resolution
The optical encoder has a code wheel with a single track of slots and two photodetectors. The photodetectors are positioned so that they produce signals with a 90 degree phase difference.
I want to ...
1
vote
1answer
34 views
gain margin and phase margin - significance
While gain margin(s) and phase margin(s) in Bode Plots of open loop transfer functions are defined at particular frequencies (when they exist) --- such as phase margin is defined at frequencies where ...
1
vote
1answer
31 views
Controls Project: Help needed finding 3rd order system
I'm in need of help finding a third-order or higher system in which I can derive a transfer function. We have a class project in which we need to find a real-life example of the system that equates to ...
0
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1answer
40 views
Motor, a gearbox and a drum with a cable lifting a mass
A lifting device consists of an electric motor, a gearbox and a drum with a cable for lifting a mass.
The speed after the initial acceleration is $v=0.5\,\text{m/s}$.
The gear efficiency $\eta=0.7$
...
0
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0answers
28 views
Offline Parameter Estimation for second order system - Ordinary Least Squares
I have a second order system which is described by the following differential equation:
$\ \ddot{y}+α_{1}*\dot{y}=b_{0}*u $
where $\ y $ is the output of the system and $\ u $ is the input of the ...
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0answers
25 views
Continuous vs Discrete system simulation in Python
Normally, when you discretize continuous system with zoh method, your continuous system output with the corresponding discrete inputs passed through zero-order hold should be the same at sampling ...
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2answers
33 views
What type of engineer/professional designs hydroponic farms?
What kind of professional/architect/engineer builds agricultural systems, specifically automated hydroponic systems?
Things such as growing, cultivation, lighting, plumbing, harvesting, processing ...
0
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2answers
32 views
Why do we analyse frequency response for step inputs?
In my class I'm in, our lecturer presented frequency response methods such as the nyquist plot and bode diagrams. Then when designing a lead compensator later, he said one of the specifications should ...
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0answers
22 views
How do I get the closed-loop transfer function of the system, fitted with a PID controller, if the input valve has a transfer function?
How do I get the closed-loop transfer function of the system, fitted with a PID controller, if the input valve has a transfer function given by:
$ \frac{Q(s)}{P(s)} = \frac{Kv}{(Tv*S+I)} $
Where Kv ...
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0answers
17 views
How to plot the response of the open-loop system when the input discharge suffers a unit step variation using LabView?
The open-loop system is a tank of water connected between two valves.
My transfer function is $ \frac{H(s)}{Q_i(s)} = \frac{R}{A R s + 1} $
My time constant is $ {Tau(T)} = {A R} $
I know how to ...
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0answers
32 views
How to derive a value from a transfer function
I have a scenario where a valve q_in(t) is pumping water into a tank of height h(t) and area A, which is then pumped out by a second valve q_out(t) that has a resistance to water flow R.
I got this ...
0
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1answer
13 views
Nonlinear behaviour of control plant and adaptive or robust design
In a paper in the context of controller design for DEAP actuators I came upon the following sentence:
Furthermore, the nonlinear behavior of the
control plant requires either an adaptive or a ...
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0answers
21 views
How to connect RFD77402 (sparkfun) proximity sensor to Arduino?
I am currently working with distance sensor (sparkfun) RFD77402, does anyone have experience with this sensor, or know how to connect this sensor with arduino? I'm confused about the wiring honestly
...
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0answers
10 views
Process control on reagent addition system
It's been a while since my fluid mechanics/process control courses at university. Due to my new role I have to dig up the old material again and start refreshing my brain!
There is one scenario ...
0
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1answer
17 views
Adjusting root locus to get a stable system from unstable system
Most of the books that I referred to, used compensators to improve transient performances of a stable system using root locus and compensator design. I got a system which is actually unstable for all ...
0
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1answer
16 views
root locus question - root locus 'begins' at finite open loop pole locations
This is a general question about root locus plots. I notice that there is a source that says:
"The root locus begins at the finite and infinite poles of G(s)H(s)".
Note the part that says 'finite ...
1
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0answers
21 views
value of $\gamma$ in the H-infinity norm
Suppose I have the system:
$\dot{x} = Ax+Bu$
$y=Cx+Du$
and the following Hamiltonian matrix:
$H=\begin{pmatrix}
A & \frac{1}{2}B^TB\\
-CC^T&-A
\end{pmatrix}$
I want to find the value ...
0
votes
1answer
41 views
Basic question about PID controller
I am a novice in control systems and just learned about PID controller.
So after watching tons of youtube videos I realized that the input of my plant is actually defined by the error. For the case ...
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0answers
37 views
effect of coupling in MIMO systems
I have a MIMO system with a 2x2 transfer matrix, for example consider:
$\begin{pmatrix}
\frac{2}{s+1} & \frac{1}{(s+1)(s+2)}\\
\frac{1}{(s+1)(s+2)}&\frac{2}{s+2}
\end{pmatrix}$
I would ...
4
votes
1answer
163 views
Block diagram vs flow chart?
I was studying a book of control system where i read that a block diagram is a specialized high level type of flow chart
So what will be the difference between a normal flow chart and a block diagram?...
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0answers
33 views
basic second order system transfer function - natural period and natural frequency
I have a question about general second-order system transfer functions. I notice two takes on this transfer function. One has a denominator of:
$$\tau^2 s^2 + 2\zeta\tau s + 1$$
where $\tau$ (tau) ...
1
vote
2answers
44 views
Root locus: ambiguity on which branch goes where?
I could not find a Controls Stackexchange, I hope this is the right place, otherwise I would be glad to post it in the appropriate section. My question concerns the root locus method.
Given a plant ...
2
votes
2answers
44 views
Controlling temperature using PIDs on two separate controllers
I have a pellet smoker, and I am customizing it for tighter temperature control. Currently, I am controlling how much material is burning to control temperature using a PID loop. I want to achieve ...
0
votes
1answer
43 views
Identification of control system type? Open loop or close loop,
What is the type of control system of door closer in attached photo?
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0answers
41 views
Adaptive feedforward cancellation (AFC) and least mean squares (LMS) for periodic disturbance cancellation
I already asked this question here, but since I did not get an answer yet I want to try it here as well:
I want to implement an adaptive feedforward cancellation (AFC) for cancellation of the impact ...
-1
votes
1answer
40 views
control systems vs artificial intelligence?(in nut shell for beginners)
i am confused in basic difference between control systems & artificial intelligence? since both techniques can be used for automation
Please kindly try to give answer in nutshell
depth/detail ...
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0answers
18 views
What are some practical applications of nonlinear control and multivariable control in the industry?
All the books I've used in my control systems class give a definition multiple-input, multiple-output systems and nonlinear systems, but all the techniques covered in the folloing chapters apply only ...
0
votes
2answers
21 views
Is learning VLSI design useful for a control/automation engineer?
I've known of a few universities that include a class about VLSI design as a part of their control/automation engineering programs. I undestand VLSI design to be about creating integrated circuits ...
0
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1answer
56 views
Controller vs Micro controller?
We often listen both term in electrical engineering? First one is seen in control systems course and second one in course of embedded systems
But what is difference between both of these terms?...
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0answers
18 views
Turbocharger boost control using two valves with a vac and boost reference for wide boost control range
Can someone explain how the above boost control setup would work. The valve on the left uses a vac source applied to the top of the diaphram which would effectively help hold the spring closed at high ...
0
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1answer
42 views
PID-control of undamped system
I general, if you model a system (pendulum for example) and you do not include damping into the system (maybe caused by friction): Is it generally possible to tune a PI or PID controller for an second-...
0
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0answers
32 views
How can I setup a controller simulator in excel?
Is there a good excel program somewhere or basic breakdown of how to implement a control loop in excel if trying to simulate the performance of a circuit? I have data from an operating plant and am ...
1
vote
1answer
14 views
Typical cycletime of an industry pid controller for servomotors
I am wondering the following. What are the typical cycletimes (or timesteps), that are used in real industry-standard pid-controllers (for example for assembly-robots on a car-production-line). I ...
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0answers
13 views
What non-Gaussian filter should I use
I am developing a filter to better predict my state of my system. I had previously tried an Extended Kalman Filter. I have all the data needed to predict my next step but I have few observations/...
0
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1answer
39 views
Does the plant transfer function of a system change with variations in the reference variable?
I am designing a PID controller for a system that requires several step changes in the reference variable (concentration of solute in a tank) over a set period of time. I can find the plant transfer ...
2
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0answers
27 views
Meaning of energy method in control theory
What qualifies a energy method in the context of control theory?
Citing from a paper to give the context in which this expression came to my attention:
One of the challenging problems of the double ...
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0answers
23 views
Auto-tuning PI controller with maximum sensitivity
I am trying to design an auto-tuning controller in matlab with the help of the paper from Astrom and Hagglund: Design of PI Controllers based on Non-Convex
Optimization* (1998). They use the maximum ...
0
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0answers
20 views
How does a digital controller's sampling period dictate the system's actuation requirements?
When selecting an actuator for a controls application - e.g. choosing a servo motor for a self-balancing robot - I understand that it's important for the actuators to have fast enough dynamics that ...
2
votes
1answer
55 views
Closed loop guidance and control: how to tune a system with multiple feedback controllers?
I'm trying to design a closed-loop guidance system for rockets - something that can be implemented in Kerbal Space Program, for example. To do this, I'm following the design process described in ...
1
vote
1answer
37 views
Designing Block Diagrams For Control Systems
I'm looking for good software to design control systems, and more specifically to neatly design "block diagrams" for control systems.
Is there something like that?
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1answer
70 views
Changing fields from mathematics to control engineering [closed]
I did my undergraduate in maths and physics and will be working in control theory for my future job. Not to my surprise, my engineering background is rather lacking. I have taken a look at materials ...
0
votes
1answer
35 views
Can i switch negative feedback to positive feedback in PID control?
I am learning Control Theory and i have a confusion about whether the following PID controllers are interchangeable or similar.
Are they equivalent? Why?
Is there any difference in how i would ...
0
votes
2answers
77 views
Is this a PID cascade control loop?
I'm working on a balancing robot. I'm familiar with the simple PID control loop but i can't understand this PID control loop.
Is this actually a cascade control loop? The programming states that the ...
1
vote
1answer
47 views
Interpreting Nyquist plot
When implementing the control for my application I got this Nyquist plot which made me flabbergasted.
If I zoom on the point $-1 + 0j$ I get the following image
How do I interpret this contour going ...
0
votes
1answer
83 views
Difference between Hysteresis, low pass filter and deadband in control theory?
I am trying to understand the fundamental difference between the following terms in the context of control systems:
Hysteresis
Low pass filter
Deadband
Are these just fancy names that can be ...
2
votes
1answer
88 views
I have a problem with my representation of roll in Simulink
I am currently an engineering student and a member of the aerospace club of my engineering school (ESILV) which is called LéoFly. We’re a team of 12 students and are building a Fusex (...
0
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1answer
36 views
How to find Performance assessment (IAE and ISE) of a PID Controlled system?
The Integral Absolute value Error (IAE) and the Integral Squared Error (ISE) is to be analysed.
A PID Controller is given as follows:
...
