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.
513
questions
0
votes
0answers
20 views
Optimal control of the gradient type PDE
I recently encountered the following optimal control problem.
The purpose of the system is to find the parameter $x$ at which the maximum or minimum of the function $f$ a is reached. $x$ is unknown to ...
0
votes
1answer
41 views
Steady-state tracking error has to equal zero, what values do I need?
A block is used to model instruments with limited capabilities to provide inputs to the plant. A seen below:
The output of the block π’π is related to the input π’ with the following input-output ...
0
votes
1answer
36 views
PID Control: Is adding a delay before the next loop a good idea?
I am implementing PID control in C++ to make a differential drive robot turn an accurate number of degrees, but I am having many issues.
Exiting control loop early due to fast loop runtime
If the ...
1
vote
1answer
47 views
What's the difference between Fuzzy PI, PD and PID controllers?
I am investigating fuzzy control and I am a little confused, I have come across 3 models and I can't quite fathom out what is going on.
In this PD+I controller, I can see the error signal being ...
0
votes
0answers
26 views
Controlling the dynamics of nonlinear systems with an unknown steady state
On the one hand, the question is simple, on the other hand, I need the help of specialists in control theory.
Let's take a simple gradient dynamical system:
$\frac{dx}{dt}=\frac{df}{dx}$
where $f=e^{-(...
-1
votes
0answers
28 views
Can a control system output follow multiple reference signals? [duplicate]
"the plant is a system, such as a heater, a car, an airplane, or a chemical process in need of some control action so that its output (it is also possible for a system to have several outputs) ...
3
votes
3answers
111 views
+50
How to convert a DC motor into a servo motor using a rotary encoder and a microcontroller?
Operating/ Rated Voltage: 24V
No load Speed: 350 rpm
No load Current: 150mA (max)
Max efficiency: 1.4 Kg-cm/300 rpm/ 14.2W/ 0.87A
Max power: 4.5 Kg-cm/180 rpm/28.2W/1.4A
Stall Current: 2.9 A (max)
...
0
votes
2answers
39 views
How to calculate frequency response of the system? and find missing values [duplicate]
I can convert the H(s) into the frequency response which is:
π»(ππ) = π(ππ/(1+ πππ))
and the output in the steady state is:
π¦(π‘) = |π»(π2)|sin(2π‘ + β¨π»(π2))
The phase: β¨π»(π2), has to ...
1
vote
1answer
24 views
What does “analytical design” mean?
What is meant by "designing analytically" ?
Especially in control systems design
Does it mean theoretically design?
0
votes
1answer
27 views
Find the point where locus crosses the damping ratio line?
Given a transfer function, find the point where locus crosses the damping ratio of 0.5?
$$G(s)= \dfrac{K(s-2)(s-4)}{s^2+6s+25}$$
The textbook only shows this solved by Matlab or program, I would like ...
0
votes
0answers
12 views
How to manage two control loops as safety when BPCS is shared?
I am trying to wrap my head around some excerpts from:
CCPS Layer of Protection Analysis
CCPS Guidelines for Independent Protection Layers and Initiating Events
IEC 61511
I am trying to understand ...
0
votes
0answers
22 views
How could we calculate the coefficient of a PI controller (ki - kp) which regulates the voltage of the DC bus link of a three-phase inverter?
From my calculations I arrived at a non-linear equation :
$$ C\frac{dV_{dc}}{dt} = 3e_q\frac{I_q}{2}V_{dc} - \frac{V_{dc}}{R_{dc}} $$
I have calculated the operating points which are $I_q = 9.58A$, $...
0
votes
1answer
26 views
Is it true that points of root locus only satisfiy the angle condition?
So , I was reading a course book : ''Modern Control Engineering '' by Ogata and I came forward this statement that made me skeptical:
''The points of root locus only satisfiy the angle - condition. ...
0
votes
0answers
19 views
Absolute Digital Encoder Speed measurement
I am using a 16-bit absolute magnetic encoder and I get the position from SSI 3 wire, I mean digital outputs for my position control application. I have a problem with getting accurate speed data. I ...
0
votes
1answer
31 views
Why not to calibrate accelerometer in IMU filters?
I have been reading various research papers regarding IMU filters and I came to the question of why do we not need to calibrate the accelerometer values as we do for the gyroscope and magnetometer?
0
votes
0answers
29 views
How to design a kalman filter with different sampling rates?
This question is related to https://stackoverflow.com/questions/22598107/kalman-filter-with-redundant-state-measurements.
How would one design a Kalman Filter (or EKF) when two measurements of the ...
1
vote
1answer
46 views
0
votes
0answers
13 views
PSCAD question regarding how to use graphs
so this question is to do with coursework, but I just need some guidance as I am not exactly sure where I'm going wrong. I missed my 2 weeks of practical classes due to my roommate having covid-19, so ...
0
votes
0answers
57 views
Choice for HEAVY blacksmith table
I have an old 7,000 lb. blacksmith table (I had it weighed at truck stop). Similar to the one this man has:
Sorry for the size of the pic.
I need to lift one end the way he is doing and I have a farm ...
1
vote
0answers
21 views
Evaluating Steady State Error Constant for a Discrete Time Control System with Kronecker Delta Input
Hello there, hope you are doing well.
I am working on a Discrete Time Control Systems homework and at a certain part of it, the question asks me to find the steady state error of the system. I ...
0
votes
0answers
30 views
How to model a double transfer function in Simulink?
I'm trying to model an actuator in Simulink based transfer functions previously derived.
One of functions is $$\omega_p=G_2(K_cG_1V_c-c)$$ where $$G_1=\frac{K_e}{\tau_es+1}$$ $$G_2=\frac{1}{c+...
0
votes
1answer
32 views
Closed loop compensator
What does it mean if you've been told to design a compensator to ensure that the closed loop phase margin is at least 120 degrees? Isn't a compensator typically designed using the open loop transfer ...
1
vote
1answer
67 views
Is using a 4x4 bolted to the face of 2x12 enough?
I am working on a project that has three 2x12βs supporting a load of 12,000 lbs. similar, but not exactly, to how joists support a house.
The 2x12βs are supporting about 6,000 lbs. on each end.
The ...
0
votes
1answer
52 views
Changing the quality of the transient process in a nonlinear system (Part II)
My question is a continuation of the topic.
https://math.stackexchange.com/questions/3910814/changing-the-quality-of-the-transient-process-in-a-nonlinear-system-in-mathemat
Unfortunately, last time I ...
0
votes
0answers
40 views
control block diagram design
I have a pump [m^3/(sV)], a tank [no units], a valve [m^2/s] and a level sensor [m/V]. The units are for the gains in the respective transfer functions. How should i connect my control block? Where ...
0
votes
1answer
43 views
Covariance of an uncertain vector going through an uncertain rotation
I have a vector $\omega$ and it associated covariance, a rotation $\mathbf R$ and its associated covariance. What is the covariance of $\mathbf R \cdot \omega$ ?
More rigorously:
I have an estimation ...
0
votes
0answers
33 views
Laplace transform and output of affine systems in Simulink
I have a system $h$ which takes as input $u(t)$ and outputs $y(t)$. It is known that the relation between $y(t)$ and $u(t)$ is affine (i.e. $y(t) = h(u(t)) = a u(t) + b$). Apply Laplace's transform to ...
0
votes
1answer
29 views
What voltage are these hydraulic valves and how to I control them?
I am building a new control system for an injection moulding machine, the last part I am trying to work out is the main pump.
It has two proportional valves on the output, one labelled throttle valve ...
1
vote
1answer
39 views
Is there any application of control engineering to the study of algorithms stability or computer science theory?
I am an undergraduate student in Electrical and Computer engineering. In our 5th semester we have a obligatory "Introduction to control systems course". I was wondering if these bunch of ...
1
vote
0answers
26 views
Regarding Question On Control System Engineering [closed]
Transfer function= 400/(s^2 + 12s + 396)
Calculate rise time, settling time, peak time, overshoot, undershoot
2
votes
1answer
43 views
Feedback loop and zero - error in steady state
I need help with this exercise. I 've tried many times with pen and paper but I'm stuck. I don't want a full answer but some feedback .
Here is my progess:
$$\frac{dx}{dt} = Ax(t) + Bu(t) \Rightarrow ...
0
votes
0answers
44 views
Changing the quality of the transient process in a nonlinear system (in Mathematica)
I urgently need advice and help.
I have a system of differential equations like this:
$\begin{cases} \frac{dx}{dt} = y[t] \cdot \alpha \cdot sin(\omega t) + \frac{d}{dt}(\alpha \cdot sin(\omega t))
...
0
votes
1answer
52 views
Numeric quadrature vs summation of running costs in model predictive control
Usually, an MPC consists of discretizing the optimal control problem in time using some numerical quadrature scheme. So the infinite-dimensional OCP reads
$$\begin{aligned}J(\vec{u}) &= \varphi\...
1
vote
2answers
66 views
How do I interpret states in the MATLAB System Identification Toolbox?
I am using the MATLAB System Identification Toolbox to estimate a 3rd order state space plant model. More precisely, the plant is a car with an Arduino mounted on it. The car takes in a PWM duty cycle ...
0
votes
0answers
32 views
How to get this hydraulic system working and help identifying parts and their function
I have recently acquired a 1982 Arburg 220-90-350 injection moulding machine, mainly just as a hobby to further my knowledge on injection moulding machines and control systems as I plan to modernise ...
1
vote
0answers
32 views
Discrete measurement - continuous observer design
I have to design a controller for the above system where the two pulse generators (red blocks ) are synchronized (measurements are only available at discrete points). However, my understanding is that ...
0
votes
1answer
44 views
Tuning Feedforward + PID Controller just with Feedforward Data
Hello there, hope you are all doing well.
Right now I am trying to design a Feedforward + PID Controller for KUKA youBot on simulation. Since I do not have the equation of the system, I am trying to ...
1
vote
1answer
29 views
Fixed end points optimal control problem
Given two points $(t_0,x(t_0)=x^{0})$ and $(t_1,x(t_1)=x^{1})$ in the $(t,x)$ plane, the objective is to find an optimal trajectory $x^{*}(t)$ such that the cost function
\begin{equation}\label{eq:1}
...
0
votes
1answer
36 views
Transfer function into block diagram and matrix form
I'm reading a book on Control System Design and running into the same issue I had in Kinematic Design. When things are presented in a format without any numerical examples it just appears as gibberish ...
-1
votes
1answer
66 views
Shouldn't linear time-invariant systems be called affine time-invariant systems instead?
For a scalar $c$, the function:
$$f(x) = cx$$
Is linear in that it satisfies the superposition property. If:
$$f(x_1)=cx_1$$
$$f(x_2)=cx_2$$
Then:
$$\alpha f(x_1) + \beta f(x_2) = \alpha(cx_1)+\beta(...
1
vote
1answer
43 views
Precision of a steeper motor and gears vs multiple motors
We are a student team trying to design a low cost CNC plasma cutting machine.
The CNC will be a table with two rails and a bridge moving on them in which the head of the plasma torch will be.
Now we ...
3
votes
3answers
207 views
Mechanism for controlling the clamping force
I am working on upgrading a research project on wind energy. They are trying to measure the performance of wind blade designs in a small wind tunnel (i.e. their models are relatively small).
What they ...
2
votes
1answer
40 views
Is there a concept of gain and phase margin for a strictly open-loop transfer function?
I'm new to control systems, and I'm attempting to analyze the stability of an open-loop transfer function. I know that by checking the locations of the poles (and ensuring all poles are in the LHP) I ...
1
vote
1answer
75 views
How can I get final value of $V_{out}$ at $t=β$ in RC circuit?
I can obtain the transfer function in this RC circuit.
$$ \frac{V_{out}}{V_{in}} = \frac{1}{(RCs+1)} $$
When $V_{in}$ is set to $10V$, how can I get final value of $V_{out}$ at $t=β$?
I tried to use ...
-1
votes
1answer
42 views
On servo loops bandwidth and tracking
Referring to article https://www.controldesign.com/articles/2018/servo-terminology-makes-a-difference/
I was unable to understand how loop gain influences the noise rejection and tracking. Taking ...
0
votes
1answer
52 views
Temperature controller using pt-1000 sensor
I need to control the temperature of a system with high accuracy with error value of $0.1$ degrees celsius +-. I will be using temperature sensor PT-1000. I need to know what would be the best option ...
0
votes
0answers
38 views
what is the name of this wheel found in toys which rotates freely?
I have tried doing search by image on few popular Internet search engines but could not get it. (sorry, it picked up lot of dust and a bit ugly to see).
I want to know the name of such wheel and where ...
-1
votes
1answer
19 views
Derivation of 2nd order damped rise time
Given the transfer function: $$\frac{\omega_0}{s^2 + 2\omega_0\zeta s + \omega_0^2}$$
How would you derive the rise time of the system from 0% SS to 100% SS.
$$t_r = \frac{\pi - \arccos{\frac{1}{\zeta}...
2
votes
2answers
14 views
Does it make sense to have a pressure and flow controller on a single closed line?
I have seen P&IDs in which a single line has both a pressure and flow control valve. Based on my understanding of Bernoulli's equation however this doesn't make sense to me - because ultimately ...
1
vote
1answer
38 views
Differential Equation for: Locking a laser's frequency with a PI controller
I think I have a good understanding of differential equations, so I would like to first try to understand my system in terms of differential equations before transforming my system into the more ...
