Questions tagged [matlab]
Use of Matlab to solve engineering problems.
102
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MATLAB allmargin() function return multiple GainMargin, but how to identify them on the Bode plot?
I have a high order discrete transfer function model which has the following form. When I use the allmargin function to get the gain margin, I get the following result:
...
- 15
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5
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Need Help in Deriving CRLB of GNSS Direct Position Estimation
I'm trying to code for the CRLB of position for GNSS Direct Position Estimation, as derived by Closas et al. in "Cramér–Rao Bound Analysis of Positioning Approaches in GNSS Receivers" in ...
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What is the effect of the resonant frequency of the system function Porter diagram on the stability of the system and how to analyze it?
I am a novice in automatic control, the theoretical basis is not very good. We have a large electric clamping jaw, single degree of freedom, the motor is controlled by the torque output, the motor has ...
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1
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Orientation and horizontal position control of a bar in 2D
I have a scenario where I have a bar of 0.1 m in length, 10N weight is applied in the center. Two forces are applied on the bar at both ends vertically, right one if 5.1 N and the left one is at ...
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Proposing a Transfer Function from a Response Graph
I need to propose a transfer function from the following graph. The K value (or amplifier gain?) we were given is 2 and it has a step response of 2 as well. When looking at the graph though it looks ...
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42
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How to Use a parameter in Matlab Simulink?
I want to include a parameter in Simulink.
For example, like the block in the picture. How to use a parameter in the gain and get the output which is L*(input), which 'L' is only a parameter, like '...
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39
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Simulink models comparison issue
I'm comparing two simulink models and in the report i'm getting the following difference. I don't really figure out what that difference is. Any idea is appreciated
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How to Determine a Valid Relationship Equation Between Two Finite Datasets -- Python, Matlab or Other [closed]
I struggled to find a clear solution online so I'm resorting to asking a fresh question.
I have two finite datasets (call them 40x1 vectors) that are equal in length and generate non-linear curves, ...
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What is the solutions of the following 1D diffusion equality using Crank–Nicolson method?
Through my research I faced to the following equality and need to find $c_i^{t+1}$. Moreover, I found that it can be solved by Crank–Nicolson method (see here: https://en.wikipedia.org/wiki/Crank%...
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Structured trianglar finite element mesh in MATALB
The available triangular mesh in the MATLAB PDE tool box here gives an unstructured triangular mesh.
How can I get a structured triangular mesh from the tool box with a similar data structure [p,e,t]. ...
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Extraction Flash Calculation - 4 Component and 2 Phase System
I am performing extraction flash calculations for 4 component and 2 phase system in Matlab. For anyone somewhat shaky with what extraction flash calculation is; extraction is performed, feed ...
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101
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Modeling a second order system in time and frequency domain
For school I was asked to model the transfer function $H(s)=\frac{3}{(s+4)(s+5)}$ in both the time and frequency domains using initial conditions $y(0)=2,y'(0)=3$, a step input, and Simulink. I would ...
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72
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Double Summation of Matrices in Convex Optimization in CVX
I want to implement the following optimization problem from the following paper Randomized Gossip Algorithms, Page 10 Eq. 53\
1- In this problem, $W$, $P$, and $P_{ij}$ are $n\times{n}$ matrices. I ...
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276
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Simulink Treating Discrete-Time State-Space as Continuous-Time?
I have a MATLAB script wherein I take a second-order ODE on $\mathbb{R}^3$ (vector field on the phase space), then, at a critical point, take the Jacobian matrix $A$, use a "fully-actuated" ...
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"Roll My Own" Integrator Block for Multiple Signals
Is it possible to create a user-defined block in Simulink (and, later, XCos) that accepts a variable number of signals (I anticipate working with mainly 12 signals but not necessarily that number of ...
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Unstable System. Error Trying to model the Red Bull Stratosphere Free Fall
I tried to model a problem months ago and still I can't solve, I don't want forget this problem so I would like to share what I tried and if you know what is happening with my graph.
This is the ...
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Why matlab returns a damp ratio as 1 for a over damped system?
I have a second order system with the transfer function as: "1/(s^2 + 5.45s + 1)", I thought it should be an over-damped system, but when I use the damp function in MatLab, it returns the ...
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333
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Reject Negative Input Simulink
Note: The design is implemented in Simulink.
Suppose I have a system wherein I am computing the sum of errors per discrete time interval. Now, I only want to consider positive errors to be summed up ...
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How do I find the gain from the root locus with given perfomance, where I know the real part of the poles?
I have an exercise to draw a root locus plot and determine its gain to make sure that it fulfills the performance requirements.
the given system G(s) is
$$G(s) = \frac{1}{s^2+s}$$
And the given ...
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Errors obtained in the numerical solution of the 1D convection-diffusion equation
I have been trying to solve the 1D convection-diffusion equation
In implementing the above, I have tried to follow closely the method described here: https://uk.mathworks.com/support/search.html/...
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2
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171
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Do I need a feedback loop while testing PID controller?
This is a homework for my university course control theory.
The task is simple: Test the P, the I and the D controllers separately to see the effect.
We don't have to connect the controllers to a ...
- 334
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995
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Pole placement with damping ratio and natural frequency
how can I find out the poles of a system if I have the damping ratio $ ζ = 0.707$ and the natural frequency $ω_n = 2.3\text{ rad/sec}$?
$A = \begin{bmatrix} -0.02 & 0.1 & 0 & -9.81 \\
-0....
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Process disturbance in PI controller help
This is the project i'm working on and i'm struggling to understand one sentence which is stopping me from progressing the project.
I'm struggling to understand what it means when it says to add +/- ...
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45
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Mixed Sensitivity Problem
I have plant,
$$P(s) = \frac{1-s/5}{(s^2 + s/4 +1/4)}$$
I am taking a mixed sensitivity approach for that I have chosen $V$,$W_1$ and $W_2$ as follows:
For bandwidth, $\omega$ =1 so I chose M as,
$M = ...
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2
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78
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Fault Recovery of a UAV using MATLAB
I'm currently investigating fault recovery in a UAV using MATLAB.
I've been given several variables:
phi = the roll angle
psi = the yaw/heading angle
beta = the side slip
p = roll rate
r = yaw/...
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64
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How I can separate a matrix into two matrices in Matlab?
I want to separate into two matrices in Matlab like this:
$$
Q=Sq^{T}Sq
$$
for example this matrix:
$$
Q=\Biggm[\matrix{92.316 &31.78&240.417\cr
31.78 &194.66 &275.47\cr
240.417 &...
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73
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Optimization with GA (genetic algorithm)
I want to optimize the below function with GA(genetic algorithm):
$$
\min_{l_{x_1},l_{x_2},l_d}||S_QS(z)||_2
$$
$S_Q$ and S(z) are defined as:
$$
S_Q=\Biggm[\matrix{6.6549 &-0.806&6.883\cr
-0....
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Plotting S parameters on Matlab
I have equations for S11 and S21 parameters for a bandpass filter which are obviously frequency dependent. I know there are commands like sparameters() and rfplot() used specifically for plotting S ...
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Why use python over MATLAB? [closed]
So in my bachelors and throughout my engineering degree, we did everything in MATLAB. But I've heard that many companies use python over matlab. Trying Python out for myself, it seems harder to use in ...
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What meaning does the following sine wave have when it comes to amplitude?
So I am getting into engineering and was curious what it means when a sine wave isn't even in a sense, at 0, from my understanding, the waveform has peak to peak amplitude of 4, while having a ...
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Is more requested MATLAB or Python in companies (for engineers)? [closed]
My question is not exactly on MATLAB vs Python in terms of features (about which there are plenty of topics yet).
It's a specific question for engineers who have a certain experience with some ...
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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 $$G_1=\frac{K_e}{\tau_es+1}$$ $$G_2=\frac{1}{c+...
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2
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How do I interpret states in the MATLAB System Identification Toolbox?
I am using the MATLAB System Identification Toolbox to estimate a 3rd order state space plant model. More precisely, the plant is a car with an Arduino mounted on it. The car takes in a PWM duty cycle ...
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How can I find deflection in a member that doesn't have a constant area moment of inertia?
I'm trying to calculate the maximum deflection in a simply supported member with a uniformly distributed load. The trouble is this member does not have a constant area moment of inertia. I've drawn a ...
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1
answer
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Regressor-passivity robot control. Help with simulation (Simulink/Matlab)
I'm trying to simulate a 2DOF planar pendulum with a regresor-passivity control, the thing is I've been having some issues with my simulation, I'm using Simulink, but in theory I know my control law ...
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1
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432
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sinking speed of particle in water
For a Newtonian fluid the sinking final speed of a metal particle is given by this equation :
while g is Gravitational acceleration , $\rho_P$ = is particle density , $\rho_F $ = is fluid density ,...
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Root Locus and Routh–Hurwitz stability criterion
A satellite launcher has a unit feedback system, whose TF global open loop is given by:
$$G_c(s)G(s) = \frac{K(s^2-4s+18)(s+2)}{(s^2-2)(s+12)} $$
a) Draw the root locus for this function
b) ...
3
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78
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Mathematical transformation of a heading angle to a roll angle
I'm trying to understand a function in a SIMULINK example of a path following UAV simulation. The gist is that, the UAV Waypoint Follower block provides a required heading from a list of waypoints and ...
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729
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How to find closed loop transfer function and use it to identify τ and k?
I have to answer a few questions on transfer functions using Matlab. The first question, which I solved without Matlab, gives a time response graph for an LR circuit, and asks me to find the first ...
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Slow integration of system ODE under specific conditions in adsorption problem
I am trying to solve the system of ODEs below. I am applying the finite differences to z, so I get a system of ODE that I can solve with a solver like ode45.
The problem is that under the conditions ...
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86
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LQR Implementation in MATLAB
I am trying to implement a simple LQR controller in MATLAB for a purely deterministic system. The code is shown below:
...
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411
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Finding coefficients for a PID controller that minimize the integral of the squared error (ISE)
The problem
The problem is to find the coefficients for the P, I and D terms of a PID controller used to regulate the object that minimize the the integral of the squared error (ISE):
$$Q = \int_0^\...
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Limiting PID controller's output making the plant unstable and untunable
I am using the PID block in Simulink and limiting the output to (+/-)5. The plant becomes unstable and untunable after putting these limits. The plant is stable and tuneable otherwise if no limits are ...
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1
answer
406
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How to calculate initial concentration of first-order reaction in CSTR?
(This question comes from a Chemical Engineering background, but basic Math and Programming knowledge is also required. I hope it still falls in the scope of engineering.stackexchange.com If not, ...
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how to implement an encoder in matlab
How can I encode a quantized vector in matlab ?
This is a part of a problem where I am asked to implement a communication block using matlab.
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Unexpected Closed-Loop System Response of Longitudinal Aircraft Dynamics
I have a closed-loop system that represents the longitudinal dynamics of an aircraft with states x velocity, z velocity, pitch rate, pitch, and x and z inertial positions. The outputs of the system (...
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Problem with performances of a control scheme
I am trying to prove with Matlab that if I have an improper system and I place poles at higher and higher frequencies the performances of the system improves. In particular I am considering the ...
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496
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How to obtain transfer function of servo?
I am using a servo motor and controlling it via arduino. Servo motor is part of a control system and I have to use System Identification techniques in order to obtain the servo's transfer function. ...
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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 ...
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212
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Solving a linear mass balance equation in the form of Ax = 0 with variables in vector x
I have been tasked with solving a series of linear equations in the form of Ax = b, where b is the zero vector. Specifically, I have a matrix E which is 4x7 and a column vector r which is 7x1, as ...
