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.
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20 views
What motors to use to guide tape with high speed
My field isn't dealing with motors and such at all, however, I now need to build something that controls two motors.
So I have two guiding reels with tape between them, similar to old tape recorders. ...
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2answers
26 views
Ideas needed: how to tilt a panel side to side [closed]
requirements:
a panel of wood 4 ft long by 2 ft wide laying flat
this panel should be able to tilt side to side (2 way)
the weight on the panel will be about 250 lbs up to 400 lbs.
controlled lift of ...
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2answers
45 views
Is the speed of a DC motor proportional to PWM?
I'm trying to control the speed of DC motor but unsure of the relationship between speed and PWM. I'm aware that the bigger the duty cycle, the larger the speed, but how exactly would this ...
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0answers
19 views
How can I model disturbances to a plant in the simulink model?
From multiple online tutorials, I have seen that disturbances to the plant are modeled as an addition of a disturbance signal to the input of the plant.
Similar to the picture below :
However, not ...
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0answers
25 views
What formula can be used to calculate the motion that will be created by unbalanced magnetic suspension?
I would like to know what formula can be used to calculate the distance that a maglev device will travel if it were to have unbalanced magnetic suspension.
Please reference the drawing below.
Say ...
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0answers
34 views
Problem with transfer function in DC Motor
I'm trying to verify whether the transfer function in this control diagram is the one stated in this document.
I tried solving it and got this:
Shifting the armature current $$I_a$$ feedback point ...
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0answers
17 views
How to implement Pade Appromixation into State Space form
I have a State Space model and I need to create an Internal delay. Therefore I want to take a certain Padé approximation and convert it to ABCD matrices and extend my current model. However I do not ...
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1answer
23 views
Unbalance voltage mesurements from 63 kV power transformer
After testing a power transformer(pt) and closing its wiring terminals I've encountered that phase S 63 kV correct voltage and phases R and T shows incorrect voltage 32 kV.
Can any body tell why?
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15 views
What is the actual difference between a control function with Securtiy Integritiy Level (SIL) II and one without?
Consider a simple example:
there's a vessel with water and a continuos level sensor (4-20 mW signal)
there's a water line with a magnetic valve, feeding the vessel
When the water level is below a ...
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0answers
36 views
Design of a lead compensator with root locus in matlab
For the transfer function G(s), I tried to design a lead compensator for the function to have a response to the step with the following specifications: Overshoot= 10%; Ts (2%) = 5s.
When I simulate ...
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0answers
30 views
how to calculate the angle in Nyquist plot
Does anyone know how i can read the angle on the Nyquist plot
without knowing the open loop transfer function?
So by only having the plot.
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1answer
28 views
How to find BIBO stability fast?
I know that for a system to be BIBO stable the eigenvalues need to be stable so real(lambda)<0
so get that is only valid for 4
but how can i find out the other systems which are BIBO stable?
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0answers
27 views
Why are these spikes while tracking the desired input
I am using a jacobian-based kinematic control for controlling a robotic manipulator to follow a desired reference. The output is showing some spikes in the task space coordinates. Why are these spikes ...
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1answer
25 views
2-Vehicles platoon stability
Given a system describing a 2-vehicles platoons that can be described as such :
$v_k$ the speed of each vehicle
$s$ the gap between the vehicles.
We can describe the state of the system as :
$\dot{...
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2answers
57 views
Activating lights using a motion sensor?
I was wondering how I would configure some sort of setup to get lights like this turn on a timer once activated by a motion sensor. I want them to turn on for about 15 seconds and then turn off once ...
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1answer
24 views
Camera and light frequency rate
I recently became curious why some lights flicker in some videos, and I read some explanation about it, and I still have some questions.
1. Does every light have to have a frequency? can it have an ...
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1answer
25 views
When is it necessary to consider digial control rather than directly coding in the gain matrix?
I designed a LQR controller and want to implement it on a microcontroller. I don't know about digital control and don't know when to apply it.
After a brief research, I found out that I need to apply ...
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1answer
22 views
How can I calculate the maximum possible deviation from equilibrium, that can still be compensated, given a limitation on the control input?
For example we have an inverted pendulum attached to a cart, with the cart having a speed limitation. Having derived the linearized model, how can I calculate the maximum possible deviation on the ...
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0answers
23 views
Is there a maximum phase margin a PID controller can give?
I'm having trouble understanding the plot attached. The bode plot here shows the bode plot of a plant to be controlled with PID. So, if I want a phase margin of 30 degrees at the bandwidth frequency, ...
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1answer
47 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
31 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 ...
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0answers
25 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. ...
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1answer
46 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 ...
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0answers
32 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 ...
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0answers
56 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 ...
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0answers
37 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 ...
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2answers
36 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
175 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 ...
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2answers
51 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
49 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
73 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
25 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 ...
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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.
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1answer
37 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.)
...
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1answer
75 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 ...
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1answer
38 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 ...
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0answers
40 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 ...
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1answer
61 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
48 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
59 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
votes
1answer
98 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
$$\begin{gather}
\dot{r} = v \\
\dot{v} = F/m \\
r(t_0) = 0\text{ m}, $v(t_0) = 0\text{ m/s}, m = 1000\text{ kg}
\...
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1answer
37 views
Learn thermodynamics before beginning with control engineering ? [closed]
I'm about to start learning about control engineering. But am I advised to learn first Thermodynamics? (Since control engineering has applications in Thermodynamics)
2
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1answer
66 views
Cruise Control Project on Toy Car
I finished taking my control theory course, and I want to build an RC car that has cruise control. So I started off with the force analysis, and I got external forces that are constant. For example if ...
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1answer
33 views
Using place command in MATLAB using different state representation
I had a transfer function
$$\frac{10s+20}{s^3+10s^2+24s}$$
and I found the state space representation of the above using MATLAB.
Using $place(A,B,[poles])$, I found a gain matrix K that corresponds ...
1
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1answer
59 views
How to control a multi input single output heating system?
I am trying to optimize the heat control of a test bench at our facility. The test bench is basically a pipe with an air flow that can be heated up to desired temperature. To heat the air flow up ...
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1answer
44 views
Transfer function with cancellable zero pole and controllability
I have a transfer function (From Ogata's Modern Control Engineering)
$$\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 ...
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2answers
73 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 ...
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0answers
21 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 $A(p)$ ...
