Questions tagged [transfer-function]

The transfer G(s) = X(s) / W(s) function describes the relationship between an input signal X(s) and an output signal W(s).

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Response of a system to a step function (Heaviside function)

I'd like to compute the response to a step function of a electrical/thermal system. Generally I can "easily" compute the transfer function $H$: $$H(\omega) = \frac{V_{out}(\omega)}{V_{in}(\omega)}$$ Since the Fourier transform ($\mathcal{F}$) of the…
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How does load force impact load inertia?

I am trying to simulate a winch as a speed-regulated motor that works through a gearbox to lift a mass. The output of the gearbox is a drum, which rotates to accumulate cable. I feel comfortable converting the mass to a moment of inertia and I also…
Chuck
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System Dynamics Modeling

I am trying to model this system but am having difficulties in setting up the equations of motion. This is a simplified model of a motorcycle suspension system, where P is the ground in the image below. In addition, the variable $u$ is the input to…
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Unexpected Results from my Transfer Function

I have a system that can be modeled with the following picture: There is a mass $m$ connected to a spring $k$ and a dashpot $d$. These are both connected to another dashpot $c$. A force $F(t)$ is applied at the junction. After some effort tackling…
anonymouse
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What do the zeros of the transfer function tell you about a system?

I come from a mathematics background and I'm familiar with laplace transforms in-as-far-as they provide an algebraic method to solve ordinary differential equations. So, when I read about transfer functions, I can clearly see the one-to-one…
Paul
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mass calculation from transfer function or bodeplot

I have a double mass rotary model. The two masses are connected by an axis which together acts as a spring damper system of the fourth order. The system is actuated by a motor and the angle of rotation is measured by rotary encoders at each end of…
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System Identification 1-d altitude control

One dimensional altitude control of a hovercraft. The model's dynamic equations that I came up with are, I treat the hover craft as a rigid particle and my goal is to have it hover at or reach a certain desired height. $$F = ma$$ $$X(t) - mg =…
user1084113
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Determine the range of values for a PI controller

This is a basic control theory question, since Control Theory is a part of applied mathematics but also of engineering I was unsure whether to ask this here. The question says: Given the transfer function of a system is $G(s)=1/(s^2+3s+2)$,…
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How to determine the dynamic response of a spring-mass system?

The Problem I have the following system for which I would like to determine its dynamic response, taken from these lecture notes pg.20: where the forcing functions are $u_1 = 1-U(t - t_0)$, $u_2=0$, and $u_3=0$, $U(\cdot)$ is the unit step function…
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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): $$Q = \int_0^\infty \epsilon^2(t) \ dt $$ The object being…
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Finding Transfer Function between specific points

Hi I have this block diagram: Now, I want to reduce it to such a block diagram: How do I find H ? I am looking for a general method, of how to approach such problems. Here is what H should be:
henry
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Which equations of a state space model influence the poles and zeroes?

In regulation, if we represent a system with a state space model, we end with three matrices A, B and C (without taking into account feed-forward part) that define a specific part of the following equation: $\dot{x}=Ax+Bu$ $y=Cx$ Is it also possible…
Crapsy
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Modelling of Ball and Beam System

I'm trying to model a basic ball and beam system using Euler-Lagrange Equation. My system looks something like this I have come up with this final Euler-Lagrange Equation: Where JB is the ball's moment of inertia, r is the radius of the ball, m is…
Zelreedy
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How do I interpret the following Bode, Nyquist and Nichols diagrams?

I am working with an arbitrarily complicated and long-winded transfer function that looks something like this: $$ H(s) = \frac{as^4+\cdots+b}{cs^6+\cdots+ds^2} $$ where letters represent constants. First I have the bod plot which has a consistently…
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Getting the damping ratio from a frequency response function v.s. transfer function

I'm trying to find the damping values of a specimen, based on sweeping the forcing frequency from 0-10 kHz. As shown in the diagram, I measure the input force from the shaker, and the subsequent response using an accelerometer on top. (The steel…
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