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Do transfer function changed in vertically placed spring damper system when an additional mass is added

Title: Calculating the Transfer Function and Displacement for a Spring-Damper System with Additional Mass I am working on a problem involving a spring-damper system, and I need help with calculating ...
sandun herath's user avatar
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17 views

Continuous Discrete State Space Properties

When we have a continuous model that we try to discretize it by using ZOH, if the first state is reachable, then what can we say about the reachability, observability and stability of the discrete ...
egemenalacali's user avatar
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Closed loop motor speed algorithms

TLDR; looking for algorithms to control a motor. I have a near-random torque, a battery current that can destroy my motor driver, and I aim for a stable output speed regardless of torque. My inputs ...
Frank Vermeulen's user avatar
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Block Diagram Reduction in Control Systems

My professor provided a code that shows the different ways to reduce a multiple block diagram. ...
walter's user avatar
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2 answers
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A question about the necessity of the observer in control theory

I am major in mathematics and also a beginner in control theory. I have a question about the necessity of observer in control theory. Take a linear system as an example, for state variable $x(t)$ ...
vent de la paix's user avatar
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3 answers
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Understanding Block Diagrams in Control Setups

Working on some automation for a Boeing 747 autopilot, I am trying to wrap my head around what sections of block diagrams like this one mean: I understand that something is being done to the yaw rate ...
Christopher Helton's user avatar
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1 answer
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Can we reshape the root locus by adding a pole instead of a zero (as is done in PD controller) to get required Ts while O.S. being the same?

I was studying about PD controllers, which made use of adding a zero at such location which gave the required settling time(Ts) while keeping the overshoot same as it was in the uncompensated system. ...
Jina's user avatar
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What is the relationship between classical control: transfer functions/frequency domain and the swing-up problem of an inverted pendulum

I am still pretty new to control theory, but I have been studying both classical and modern state space/optimal control ideas. I am having trouble understanding what the frequency domain/transfer ...
krishnab's user avatar
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How to design the control loop to synchronize two rotational objects?

There is a rotating object (object A) that rotates at about 50 rpm. Its rotational speed may change slowly. I need to control another object B via a variable frequency motor, so that the objects' ...
Jackoo's user avatar
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1 answer
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Does H infinity control have to be limited to a simple 1Dof feedback architecture?

So I understand how H infinity control can be used to synthesize a controller that is in the standard error-feedback framework shown here: https://www.researchgate.net/figure/1-DOF-feedback-control-...
Quéston Questioneer Esquerie's user avatar
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Type of Lyapunov surfaces corresponding to a specific Lyapunov function

Consider the following Lyapunov candidate function: $$ V(x,y,q_i) = \frac{1}{2}x^2 + \frac{1}{2}y^2 + \sum_{i=1}^{n}\ln\big(\cosh(q_{i})\big) \tag1$$ where $q_{i} = \sqrt{(x-x_{i})^2 + (y-y_{i})^2} - ...
Teo Protoulis's user avatar
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2 answers
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Discretization of a PID controller

I've been given a plant transfer function to control trough a PID. The transfer function is: $G_{\small{p}}(s) = \frac{1}{(1+s)(1+2s)}$ Doing a little work with matlab I got this PID controller ...
weirdgyn's user avatar
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CubeSat: When designing the PID Controller of the CubeSat, what are some constraints that you need to take into account?

For a 1U CubeSat project in which we need to design the controller for it. We decided to not include any propulsion system to keep it light, we'll just essentially drop the satellite on LEO and let it ...
tadm123's user avatar
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How to setup integrator action when using full-state feedback?

So I have a state-space system, \begin{eqnarray} \dot{\mathbf{x}}&=&A\mathbf{x} + B\mathbf{u}\tag{1}\label{EqSS}\\ \mathbf{y}&=&C\mathbf{x}\\ \end{eqnarray} where, \begin{eqnarray} \...
wolfiesax's user avatar
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Why does a lead compensator with little phase contribution reduce the overshoot of the system so dramatically

I am currently designing a lead compensator to allow the following system to conform to some specific requirements: $$ G(s)=\frac{2}{s(s+2)(s+5)} $$ When using the angle criteria to meet these ...
John Bach's user avatar
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Is it theoretically possible to control an continuously flexible inverted pendulum?

We can control an inverted pendulum relatively easily with PID. We can control a double-inverted pendulum with more sophisticated methods. Lately, a triple inverted pendulum was controlled, with 56 ...
sebzuddas's user avatar
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Using Relay and contactless water level sensor to switch on or off motor pump

I have no prior experience related to electrical projects and I am having confusion about which type of relay and how to connect relay, contactless water level sensor and motor pump. So basically I ...
Basmati_Reis's user avatar
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VDI Guideline 2143 Sheet 1: Motion rules for cam mechanisms; theoretical fundamentals

Hello Motion Control Enthusiast, I am a motion control student, and looking for your suggestion for a Free downloadable English-translated version of VDI Guideline 2143, theoretical fundaments of cam ...
Hansen Micheal 's user avatar
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1 answer
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Cost/Objective Function Normalization (MPC)

I am trying to develop an MPC. In this MPC, I predict the temperature and try to bring the sensor value to the desired setpoint temperature. I predict the temperature in the next 180 minutes for the ...
Clankk's user avatar
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Control techniques for linearized systems (I.E. a linearized DC-DC boost converter)

I have a linearized model of a DC-DC boost converter, in matrix form: $x' = Ax + bu + d$ (the two "x" states are the input inductor current, and the output capacitor voltage) For controlling ...
rt54321's user avatar
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1 answer
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How and why is kinematic control implemented?

First off, I apologize for what is likely a rather broad and formless question (and an even more broad and formless title). I'm a mathematician whose work sometimes carries him to control systems due ...
infinitylord's user avatar
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1 answer
268 views

Why is it true that the velocity error constant can be read from the Bode diagram at the frequency w=1 rad/s?

I am trying to find a proof as to why we can read the velocity error constant $K_v$ of a closed-loop directly from the Bode diagram. That is, why the following is true: $K_v = \frac{|L(j\omega)|}{\...
ddmcp's user avatar
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I need to design a controller for a system, need to choose between P, PI, PD, and PID, given only the desired ss, settling, and overshoot %

(Apologies for terrible formatting, first post and don't know how to make equations look nice) The system is $$G(s)=\frac{10}{4s^2+7s+23}$$ and the requirements are steady state error of zero, $10ms$ ...
Logan Harris's user avatar
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1 answer
87 views

How does frequency-response and lead-lag compensators fit in with PID or State Space control

I am new to control theory, as my background is in statistics. In watching a wonderful set of lectures by John Rossiter, and am feeling pretty comfortable with my understanding of the basic concepts ...
krishnab's user avatar
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Calculating residual in a system based on parity space approach

I am reading the book Model-Based Fault Diagnosis Techniques, where the chapter on Residual Generation Methods has a section on the Parity Space Approach. Here, it is said that residual $r(k)=(y_s(k) −...
Dipsy2000's user avatar
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Output error vs equation error

We are learning about the parity space approach in class and we were given this figure to demonstrate the output error and equation error. [![Output and equation error][1]][1] My question is what are ...
Dipsy2000's user avatar
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1 answer
56 views

Creating a recursive control system

I am trying to design a digital control system of which output depends on the difference between 1 input signal 1 tick ago and the output 1 tick ago ,and 1 another input signal. The output $y(n)$ = ...
Cerise's user avatar
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1 vote
1 answer
64 views

Partial derivative of change in state with respect to multiplicative faults

I am reading the book "Model-Based Fault Diagnosis Techniques" by Steven X. Ding. Here, they describe a system with the equation $$ ẋ = (A + ΔA_F)x +(B + ΔB_F)u+E_f f$$ Then, $$ ΔA_F = ...
Dipsy2000's user avatar
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4 answers
502 views

What is the physical intuition behind an "integrator" in control theory

I am watching some videos on control theory by John Rossiter, and they are very good. So far I have watched most of the videos on classical control, including transfer function, feedback, etc. One ...
krishnab's user avatar
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2 votes
1 answer
167 views

State space representation of a 2 tank system

I am figuring out the state space equations of a connected 2-tank system. For the 1st tank, the state space equation is as follows : ...
Dipsy2000's user avatar
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1 answer
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Final form of transfer function in a single input single output system

I am reading the textbook "Modern Control Engineering" by Katsuhiko Ogata. There is a section on deriving the transfer function from the state space equations dx/dt = Ax + Bu and y = Cx + Du ...
Dipsy2000's user avatar
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1 answer
930 views

Transfer functions of a closed loop system subjected to a disturbance

There is a system with two controllers in series having the transfer functions G1(s) and G2(s) which is separated by a summing point through which the disturbance D(s) enters the system. The output ...
Dipsy2000's user avatar
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Model mismatch and bias in Smith Predictors

I have a question pertaining to Smith Predictors (see below for reference). Given a plant P and plant model Gp, I believe model mismatch is irrelevant in steady state. In steady state, delay-less ...
Danny Gelman's user avatar
1 vote
0 answers
149 views

Obtaining the open loop gain - (estiamte the gain and phase frequency response)

This post is related to the following stackexchange link but in this new question, I am focusing on describing the controller and going over my process of obtaining the open loop vs closed loop gain: ...
CakeMaster's user avatar
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1 answer
73 views

controls - how to measure phase margin for low gain system

I have a closed loop system with the corresponding gain and phase plots shown below (note frequency is normalized). I am interested in identifying the phase margin and gain margin of my system. In ...
CakeMaster's user avatar
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Some questions about model predictive control (MPC)

I have some questions about model predictive control (MPC) How does MPC use a system's model to forecast its future response? How do model uncertainties and mismatches affect the performance of MPC, ...
u1997's user avatar
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1 answer
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How do you linearize this nonlinear system?

The system equations are: $$ \ddot{\theta} = -\alpha \; |\theta| \; \theta + \sin(\theta) - \tau $$ $$ \tau(t) = 20 \; e^{-20t} \; v(t) $$ The system state space description is: $$ \mathbf{x} = \begin{...
Noisy Humbucker's user avatar
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0 answers
70 views

How to implement H-infinity controller in STM32 platform?

I used matlab to simulate some H infinity controllers, and I have some understanding of the related theory. But I don't know how to implement H-infinite controller on STM32 platform using C/C++ code. ...
zymaster's user avatar
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1 answer
666 views

What is the Z transform of the Discreate PI control model?

I have a discreate PI controller implemented in stm32 MCU, it has the following form: $$ PI=K_p\cdot[r(t_i)-y(t_i)] + (K_I)\cdot\sum_{n=0}^{i}[r(t_n)-y(t_n)]\cdot\Delta t $$ where $r(t_i)$ is the ...
zymaster's user avatar
0 votes
1 answer
65 views

Multiloop feedback control system find closed loop gain

I want to find the closed loop gain of this block diagram: I remember a rule that since these 2 loops collide with each other we ignore them so is the closed loop gain just equal to $\frac{H_{1}(s)}{...
Volpina's user avatar
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1 vote
1 answer
43 views

Routh's algorithm and root analysis give contradictory results

I am designing a control system : with open loop gain equal to : $\frac{K}{s(s^{2}+4s+3)}$ The closed loop gain is obviously :$\frac{K}{s(s^{2}+4s+3)+K}$ I tried finding the critical frequency but ...
Volpina's user avatar
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2 answers
90 views

Different kinds of control loops

I am wondering about different categorizations of control loops. One categorization differentiates control loops with respect to what inputs they take: Open control loops. Closed control loops. 1a. ...
user110391's user avatar
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1 answer
57 views

Error Equation of a Control Loop

I want to calculate the error of a control loop. Therefore, the system and the general processes and models are defined as follows: The equation for error is described as follows: I do not ...
Rayleigh's user avatar
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143 views

What is the intuitive explanation for why a system can be stable with a negative gain margin?

Beyond the math which shows that a gain of -1 and a phase of -180 (G(s)=-1)causes instability when the open-loop TF is taken to closed loop, the way I've always justified the instability of G(s)=-1 ...
jgholder's user avatar
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1 answer
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How to re-write systems of two linear second order ODEs in a state space form

I have recently been working on how to convert ODES into state space form, and I came across this problem that has me confused. Should B in the state space be [1; -2] or [1 0; 0 -2]? I think the ...
Ray's user avatar
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1 vote
0 answers
45 views

How often is discrete-time control used in industry?

Although in reality I know that computers handle all systems in discrete time, in my limited industry work experience I've only used continuous-time control system analysis/standard frequency domain ...
jgholder's user avatar
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1 answer
138 views

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: ...
zymaster's user avatar
1 vote
1 answer
70 views

why Type III systems has at least two gain margins?

I heard the following statement https://engineering.stackexchange.com/a/54322/40848 if we have a type III system, or one that has three or more low-frequency poles that we're closing around, then we ...
zymaster's user avatar
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2 answers
97 views

Why are the phase indicators different between the open loop bode plot and the closed loop bode plot?

I have an open-loop transfer function G num=105*conv([1 1],[1 2 43.25]); den=conv([2 0 0],conv([1 2 82],[1 2 101])); G=tf(num,den); and a closed-loop function of G/(1+G). Here are the open-loop bode ...
zymaster's user avatar
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1 answer
84 views

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 ...
zymaster's user avatar

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