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.
-1
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0answers
25 views
how to determine the transfer function for block diagram which is given below [on hold]
how to determine the transfer function for block diagram which is given below
0
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1answer
35 views
Control system for a temperature controller
I have adapted a refrigerator to create a temperature controlled environment for brewing beer. I have mounted an electric heater coil inside the fridge and configured a basic controller to maintain a ...
2
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0answers
26 views
How can I find left and right directions associated with each zero for a MIMO transfer function?
How can I find left and right directions associated with each zero for a MIMO transfer function?
Intia
First it can be expressed in Smith-McMillan form and can find poles and zeros. Then how to find ...
1
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0answers
23 views
Modeling Water Flow Through Saturated Medium
I am working on a project that uses a variable-speed pump to achieve a desired pressure across a medium (coffee grounds). The system includes a pressure sensor in-line between the pump and the medium. ...
1
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1answer
39 views
Control: control action of a PID controller with feedback
I'm programming the controller for a drone and I've got a question that may be basic, but I need to understand this perfectly to continue with the most interesting part of the project.
The sensors of ...
1
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0answers
30 views
What is the principle behind controlling thermoacoustic combustion instability with a speaker?
From "ThermoAcoustics and the Rijke Tube: Experiments, Identification, and Modeling", thermoacoustic instability can be subsided using an amplifier and a speaker.
It says in page 4,
The microphone ...
1
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0answers
34 views
3 DOF SISO state space control
As part of a control systems course I have to implement control for a 3 DOF SISO mass spring damper model of a robotic cutter arm. The arm is to follow a 5Hz triangle wave reference which is ...
1
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0answers
35 views
Simulating a mass - spring - damper system
I have a mass - spring - damper system with external force and I am trying to simulate it using Matlab. I want to have a linearly parameterized form and use the least squares method to find the ...
0
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0answers
8 views
How to Calculate the Speed Ratio between two rollers (overdrive of take-up roller) to provide a required Tension web tension
I have a web feed system with a re-winder and I need to apply a tension to the web. I have a driven roller and a take-up roller. I need to calculate how much overdrive to supply to the takeup roller ...
0
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0answers
17 views
Calculate additive RPM required in Feed Forward Web Tension Control
In a web tension control system, where feed forward is to be used; a tension set point is desired lets say 20lbs. A load cell system provides feed back A roller on top of two load cells). There will ...
1
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2answers
34 views
Can an AC rated temperture switch be used in a DC control circuit?
Looking to add a "high oil temp" warning on a machine tool by adding a temperature switch into the hydraulic circuit, right after the radiator before returning to tank. I know monitoring from the tank ...
1
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1answer
167 views
What is the straightest, longest and strongest pole that could be launched into space?
Which of these poles would be straighter and stronger then the others?
These are some poles that are compacted making them possible to send to space. Sending a single solid pole .5km long will not be ...
0
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0answers
40 views
load in a stepper motor
I want to move a 7 kg object linearly, using a stepper motor.
How can I determine the torque required by a stepper motor depending on the load?
0
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2answers
45 views
Books for learning PID control? [closed]
I am aiming to program a quadcopter flight controller as a personal project.
To be able to do this I understand one of the fundamentals is a PID control system . So my question is does anyone have ...
1
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1answer
48 views
How are all LTI systems also dynamical systems?
How are all LTI systems also dynamical systems?
I understand that LTI systems are linear and time invariant and that dynamical systems describe how one state develops into another, but how would this ...
3
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1answer
63 views
What is the most common control method in Underfloor heating?
I am trying to research the common methods on an underfloor heating system that are available in the market.
I know there are usually,
On/Off control to control the flow of water into the pipe
...
1
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1answer
22 views
State observer for speed estimation from encoder
I try to implement a state observer (Luenberg Observer) to estimate the speed of my motor. Only the absolute position of the motor can be measured and I want to take into account also the target ...
0
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1answer
38 views
Zeros of a Trransfer Function
I would be grateful if someone could explain me what does the value of zeros of a transfer function tell about the dynamics of the system.
0
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1answer
35 views
how to filter model-free observations (e.g. Kalman filter)
Before asking a question, I have no background knowledge of engineering. So I have no idea about these issues like control or signal engineering. (Also, I'm not good at using English. sorry for that.)
...
0
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1answer
45 views
Programming a gas mass flow controller rig
I'm trying to upgrade a multiple gas flow controller, which must be capable of controlling the mass flowrates of three gases independently through one outlet line to our system, and am in need of a ...
0
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1answer
36 views
The relationship between the I control and the stability margin
While I'm reading the paper, it said
"The I control can makes the phase lag, so it can makes stability margin reduced."
Words are not same as that, but the meaning is the same.
How the I control ...
1
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0answers
37 views
What is the connection between PID and feedforward controllers?
They are tightly connected as some concepts of feedforward is based on PID algorithms, and both of them are control systems. But when I see a phrase such as "Feed forwards augment PID control", I'm ...
1
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1answer
57 views
Control of second order undamped system
I have the following differential equation:
$$\ddot{\psi_t} + \omega^2 \psi_t = \omega R_s i_f - \omega u_f + \dot{u}_t - R_s \dot{i}_t$$
where $w$ is the electrical speed of the motor.
I have ...
0
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1answer
28 views
If I replace a flow orifice with a Coriolis flow meter of the same size do I need to worry about pressure drop with the new Coriolis meter?
I have a 3 inch line with a 1.5 inch flow orifice. If I take out the flow orifice and put in a 1.5 inch coriolis meter will the pressure drop be the same or better with the new coriolis meter than ...
3
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1answer
45 views
Constructing a block diagram for amplitude control of an oscillator
I'm building a Wien Bridge oscillator. The oscillation part works just fine, but it currently limits on the supply rails.
I want to add amplitude control, so I've added a precision rectifier which ...
1
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1answer
52 views
simulation of an attitude optimal Backstepping controller based quaternion for a UAV in MATLAB
I'am trying to implement this open access research article Attitude Optimal Backstepping Controller Based Quaternion for a UAV
I did not find the same result in this paper Can anyone tell me where my ...
3
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1answer
93 views
what's wrong with this robust control scheme?
I'm learning how to control a double integrator with $H_\infty$.
my model is simply
$$\begin{gather}
\dot{r} = v \\
\dot{v} = F/m \\
r(t_0) = 0\text{ m}, $v(t_0) = 0\text{ m/s}, m = 1000\text{ kg}
\...
0
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1answer
35 views
Learn thermodynamics before beginning with control engineering ? [closed]
I'm about to start learning about control engineering. But am I advised to learn first Thermodynamics? (Since control engineering has applications in Thermodynamics)
2
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1answer
60 views
Cruise Control Project on Toy Car
I finished taking my control theory course, and I want to build an RC car that has cruise control. So I started off with the force analysis, and I got external forces that are constant. For example if ...
0
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0answers
40 views
Using an unstable controller that gives a stable closed loop performance
I have system with controller (a state-space system with 0 reference input; this is the equivalent transfer function representation)
$$\frac{9.1 s^2 + 73.5 s + 125}{s^2 + 17 s - 30}$$
which is ...
1
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1answer
31 views
Using place command in MATLAB using different state representation
I had a transfer function
$$\frac{10s+20}{s^3+10s^2+24s}$$
and I found the state space representation of the above using MATLAB.
Using $place(A,B,[poles])$, I found a gain matrix K that corresponds ...
1
vote
1answer
50 views
How to control a multi input single output heating system?
I am trying to optimize the heat control of a test bench at our facility. The test bench is basically a pipe with an air flow that can be heated up to desired temperature. To heat the air flow up ...
0
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1answer
41 views
Transfer function with cancellable zero pole and controllability
I have a transfer function (From Ogata's Modern Control Engineering)
$$\frac{s+2.5}{(s+2.5)(s-1)}$$
and the theory says the system has a pole zero cancellation and is uncontrollable.
They said that ...
0
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2answers
60 views
LQR control and system dynamics linearization
I recently finished a project that simulated the dynamics and control of a 6DOF quadcopter model using a state-space LQR control approach, but I had a few questions that I wanted to ask that might ...
1
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0answers
20 views
2
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1answer
47 views
Does the controllability of nominal system imply the controllability of the actual uncertain system?
Given a system dynamics
\begin{equation}
\dot{x}=A(p)x+Bu,
\end{equation}
where $A(p)$ is the uncertain system state matrix with the nominal matrix being $A(p_0)$. The uncertainty in $A(p)$ ...
0
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1answer
34 views
How to identify the time delay of manipulated variables which are important to the final quality of polymer product
In a polymer production process, there are a lot of manipulated variables(MV) such as temperature ,pressure , or level of reactor that affect the quality of my polymer product.
However, it usually ...
0
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0answers
35 views
Nonlinear state space model example
Is there any (preferably well-known) example of a nonlinear state space model of a system in the following form?
$x(k+1)=Ax(k)+f(x(k))+u(k)\\
y(k)=Cx(k)$
where $f(\cdot)$ is a nonlinear function of ...
0
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0answers
20 views
Doubt regarding relation between maximum of $||x||$ and $x^TAx$ with regards to attitude dynamics
I was dealing with 3-DOF attitude dynamics of rigid body and wanted to comment upon the following defined function $F$ at its maxima.
Consider $F \in \mathbb{R} : F(e_{\Omega}(t)) = \frac{1}{2}e_{\...
1
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1answer
56 views
Order of a transfer function and its properties
I hope this is the right place to ask since I couldn't find a control systems SE.
Lets say we have the transfer function $P(s) = \frac{1}{s(s+15)(s+10)} = \frac{1}{s(s^2+25s+150)}$(completely made up ...
0
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0answers
20 views
Separation principle for a linear system with disturbances
In publication
Mayne, David Q., et al.
"Robust output feedback model predictive control of constrained linear systems."
Automatica 42.7 (2006): 1217-1222.
it is ...
1
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0answers
26 views
Extended Kalman Filter formulation
For a nonlinear system,
$$
\begin{align}
&{\boldsymbol x}(k+1)={\boldsymbol f}({\boldsymbol x}(k),{\boldsymbol u}(k),{\boldsymbol w}(k)) \\
&{\boldsymbol y}(k)={\boldsymbol h}({\boldsymbol x}(...
0
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0answers
17 views
Slip efficiency with optimal control inputs
I have developed an equal slip controller in order to maximize the slip efficiency of a tire. Slip efficiency is a component to traction efficiency that is formulated as followes:
$$\eta_t =\frac{F_x ...
0
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0answers
17 views
Controller design for a thrust angle constrained tracking for a 3-DOF system
For the given system:
\begin{equation}
\begin{aligned}
\dot{e_x} &= e_v \\
m\dot{e_v} &= mge_3 - m\ddot{x_d}(t) - f
\end{aligned}
\end{equation}
which is the translational part of position ...
2
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2answers
51 views
Requirements for realtime control
What are the requirements to call a controller real-time?
What are the entire standards for that?
I do not think that just rendering the output quickly before the sampling interval passes is ...
1
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1answer
220 views
Kalman filters vs. state observers
What is the difference between a state observer and a Kalman filter? Having implemented various types of Kalman filters, I'm still a bit confused, mainly because state observers require the selection ...
0
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0answers
52 views
Can a quadrotor track a perfectly horizontal and straight trajectory?
We know that the only control action provided by a quadrotor system is through the propellers. Now, assume that I want to track $x(t), y(t), z(t) = (t,0,0)$. Can we ever develop a controller which ...
0
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0answers
23 views
Equal prediction and control horizon for nonminimum phase systems
In paper,
Lee, J.H. and Yu, Z.H., 1994. Tuning of model predictive controllers for robust performance. Computers & chemical engineering, 18(1), pp.15-37.
They have proposed an MPC tuning ...
1
vote
1answer
25 views
Maximum MPC prediction horizon for an unstable plant
In the following book,
Model Predictive Control ToolboxTM (User's Guide)
Alberto Bemporad
Manfred Morari
N. Lawrence Ricker
At page 1-6, it has been ...
1
vote
1answer
26 views
impulse input and discontinuity in initial condition after
Consider a dynamical system as bellow that is subjected to an impulse input:
$\sum_{n=0}^N {a_n x^{(n)}}= f_0 \delta(t-t_0)$
the initial values are non-resting (all non-zero):
$x(t_0^-)=x_0\hspace{...
