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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2answers
20 views
Why does a lead-compensator type system decrease to a step response
For example, the step response of $\frac{s+1}{s+2}$ is decreasing although its gain is +1, and this system has higher gain at high frequencies than low frequencies based on its Bode plot. But if I ...
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0answers
23 views
Output matrix for system with accelerometer
Consider a generic second order state space SISO system
\begin{equation}
\left[ \begin{array}{c}{\dot{\tilde{x}}_{1}} \\ {\dot{x}_{2}}\end{array}\right]=A \left[ \begin{array}{c}{\tilde{x}_{1}} \\ {\...
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0answers
13 views
How can I tune the parameters of a lqr controller?
From my internet research, it seems there's no systematic way of tuning the design parameters for the LQR controller. I have found Bryson’s rule as an initialization. However I don't know how to ...
0
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1answer
36 views
What is the appropriate type of controller for this system?
I am given this transfer function for a system:
$T\left(s\right)=\frac{9.81}{s^4+0.5s^3+11.2815s^2+4.905s}$
Now, I want to design a controller that will make the closed loop system have an overshoot ...
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0answers
31 views
Digital control implementation in MCU
I have implemented a PI compensator for an integrator plant through floating point variables and everything works fine. The design intent is tracking filter and it does not track well the input signal....
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0answers
37 views
Control law for nadir pointing spacecraft
Hoping someone here can give me some advice. I've been trying to build an orbit and attitude propagator inside MatLAB and have run into some issues with the attitude propagation due to my lack of ...
0
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1answer
18 views
How can I damp oscillating behaviour caused by quantization in a digital control system?
After introducing a quantization block in the simulink model, the output of the controlled system starts to oscillate around the zero fixpoint.
I am using a lqr controller to regulate the system, ...
0
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1answer
25 views
How to design a transfer function for a Model Rocket?
I am building a roll stabilized model rocket. I am beginner at controls systems. How do I find out the transfer function of the rocket. Although, I am aware of definitions and stuff of control systems....
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1answer
43 views
Discrete PID controller
I need the equation of a discrete PID controller and I find different answers from different websites. For example, here the answer is:
$$u[k] = u[k-1] + (K_p + K_i \frac{T_s}{2} + \frac{K_d}{T_s}) e[...
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0answers
24 views
Power generation in combustion engine
Here's the problem:
On the one end of low-speed engine (driving end) I can measure the torque transformed to mechanical energy. On the other end (free end) I'd like to join power generator with a ...
1
vote
1answer
54 views
Strange simulink error. Professor & TA don't know. Any Ideas?
I am currently working on developing a simulation for a restricted UAV, and I’m having some issues with Simulink while doing this. I have my mathematical equations which have been approved by my ...
2
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1answer
56 views
PID control of a DC motor with PWM from Raspberry Pi - how to cross dead area?
I'm driving a DC motor (actually a linear actuator) with a Polulu motor controller from a Raspberry Pi. The motor drives if you ask for anything between 20 and 100% duty cycle, so there is a dead zone ...
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0answers
28 views
Name of protocol used to communicate with Fuelling Station Dispensors
I am trying to figure out the actual (Range of ) communication protocols used to communicate with Fuel Dispensers at fuel retail outlets.
I see them write 2-wire protocol which is not specific as ...
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0answers
30 views
Defining transfer functions in MATLAB properly
So for a robust control problem I had to use a weighting function of the form:
$$ W_P=\frac{0.5s+0.05}{s} $$
And I do so by
...
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0answers
31 views
Can one move the zeros of a transfer function?
This may be a very simple question and I think I know the answer but I would like it to be confirmed by somebody else.
My questions regard the zeros of a systems (the roots of the numerator of a ...
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0answers
24 views
What motors to use to guide tape with high speed
My field isn't dealing with motors and such at all, however, I now need to build something that controls two motors.
So I have two guiding reels with tape between them, similar to old tape recorders. ...
0
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2answers
33 views
Ideas needed: how to tilt a panel side to side [closed]
requirements:
a panel of wood 4 ft long by 2 ft wide laying flat
this panel should be able to tilt side to side (2 way)
the weight on the panel will be about 250 lbs up to 400 lbs.
controlled lift of ...
1
vote
2answers
67 views
Is the speed of a DC motor proportional to PWM?
I'm trying to control the speed of DC motor but unsure of the relationship between speed and PWM. I'm aware that the bigger the duty cycle, the larger the speed, but how exactly would this ...
0
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0answers
27 views
How can I model disturbances to a plant in the simulink model?
From multiple online tutorials, I have seen that disturbances to the plant are modeled as an addition of a disturbance signal to the input of the plant.
Similar to the picture below :
However, not ...
1
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0answers
40 views
Problem with transfer function in DC Motor
I'm trying to verify whether the transfer function in this control diagram is the one stated in this document.
I tried solving it and got this:
Shifting the armature current $$I_a$$ feedback point ...
0
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0answers
21 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 ...
0
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1answer
24 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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0answers
18 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
43 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
34 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.
1
vote
1answer
35 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?
0
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0answers
28 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 ...
0
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1answer
27 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{...
0
votes
2answers
61 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 ...
0
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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 ...
0
votes
1answer
29 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 ...
0
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1answer
26 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
31 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, ...
0
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1answer
52 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
38 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
vote
1answer
34 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
52 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
33 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 ...
2
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0answers
72 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
39 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 ...
1
vote
2answers
38 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
vote
1answer
189 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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2answers
57 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
vote
1answer
50 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
votes
1answer
74 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
vote
1answer
28 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
40 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
39 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
124 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
40 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 ...
