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Questions tagged [pid-control]

171 questions
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Best PID autotuning algorithm/library for simple heater problem

It's the 21st century, anything is possible. Except for PID autotuning for a simple problem, heating/cooling system - make robust and ready to use solution. I've found only one library for PID autotune:…
artsin
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Limiting the integral to a time window in PID controller

Would it make sense to integrate e(t) from t - c to t instead of 0 to t for the integral part of the PID controller? What are the most common deviation from classic PID controller definition?
Tarik
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3
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Model-based Ziegler-Nichols tuning of a hover PID controller

Doing a fun project to reconnect with my engineering training: I would like to design a control scheme for hovering in-place at a set altitude with a vertically-oriented propeller, rocket, etc. Right now I'm not even worried about lateral motion,…
Noah
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Improving a PID controller from logged historical PID data

Part of our system involves a feedback loop with a PID controller. We log every call to the PID controller, and include in the log information about the Kp, Ki, Kd, the set point, the input, output, timestamp, etc. Surely we can use this historical…
Cam.Davidson.Pilon
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Is this function common in PID controllers?

I'm reading some old microcontroller code for a PID algorithm. There's a strange function (to me) that seems to work like this: $output = \frac{1}{n}input + \frac{n-1}{n}previous\_output$ The value $n$ varies. Over several iterations, it will…
John B
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Tricks for controlling process with logaritmich characteristics over 20 orders of magnitude

I'm building a machine that operates over 20 orders of magnitude with logarithmic process characteristics. I have tried regular PID and also all sorts of variations of PID and did not get good results. What other alternatives to PID I have? I start…
Doege
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What means the velocity constant of the integration in PI controller formulas?

I have an equation of a PI controller. What means here the velocity constant "R" exactly? $$m(t)=K(e(t)+R{\int}e(t)dt)$$ $$R=1sec^{-1}$$
gamliel basha
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Can I charge 18650 Li-ion cell from 5 V USB?

I've got a flashlight with a 3.7 V 18650 cell that charges with a 3.5 mm barrel plug. They provided adapter that says 4.2 V +/- 0.5. Can I use a 5 V USB to barrel plug adapter to charge it? UPDATE So the adapter clearly says +- .5 v. Is this an…
Andyz Smith
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PID Gain Calculation

A component of a control loop is approximated by the following relation between input $x$, and output, $y$: $y = 5x^2$ During normal operation, the value of input to this component ranges between $1$ and $1.5$. In stability analysis of the overall…
fraiser
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Designing a PID controller for a Type 1 System

I don't know if this is the right place to ask this so I'll give it a try. Given the following system, for example $$ P(s) = \frac{40}{s(s+4)}, $$ I have to design a PID controller that must satisfy the following requests: the error for a unit ramp…
aghin00
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Do you need to reset the Integral part of a PID controller?

I'm learning about PID controllers and one thing I don't quite understand from the pseudocode and formulas is the apparent persistence of the "Integral" portion. For example, imagine the position is low and is adjusted with minimal oscillation to…
CaptainCodeman
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Equal proportional and derivative gains of PID

Is it common to take equal values for the proportional and derivative gains of a PID controller? if so what does it mean?
Mohammad
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