# Questions tagged [pid]

Proportional Integral Derivative Controller. A type of control algorithm used in many control situations, especially servo systems.

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### PID control against sine wave error

I'm writing a PID to control a toy car that follows a black line on a circuit. I've tuned my PID and it works at high speed for all the circuit except the winding section. For that, the error signal ...
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In continuation of the question I asked here: Quadcopter instability with simple takeoff in autonomous mode ...I'd like to ask a few questions about implementing a basic PID for a quadrotor ...
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### How to know the desired orientation of a quadcopter?

I am trying to simulate a quadcopter model on Simulink. I want to implement a PID controller for each of X,Y,Z and phi,theta, psi angles. PID gets the error, as input, which is to be minimized. For ...
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### Quadcopter instability with simple takeoff in autonomous mode

I'm trying to get a quad rotor to fly. The on board controller is an Ardupilot Mega 2.6, being programmed by Arduino 1.0.5. I'm trying to fly it in simple autonomous mode, no Radio controller ...
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### Pre-built PID motor controller [closed]

I lead a university robotics team that needs PID controllers for four drive motors and two additional motors that are used in a secondary system. I would strongly prefer to buy pre-built PID ...
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### Field oriented control of brushless motors

If I was controlling a normal brushed motor as a servo, I would measure the motor's position, and adjust the PWM signal to control the voltage. This way I could achieve a precise velocity/position ...
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### How to control the position of a pneumatic piston?

How can I control the position of a pneumatic piston? The only way I know about is using a magnetic reed switch (magnetic sensor) with a matching piston and use some type of control algorithm, like ...
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### Approach to using PID to get a differential robot driving straight

Consider a differential drive robot that has two motorized wheels with an encoder attached to each for feedback. Supposed there is a function for each DC motor that takes a float from -1 to 1 and sets ...
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### Help with PID "units" in a quadcopter control system

I'm in the process of writing my own simple quadcopter controller for experimental use, and I'm having trouble getting my head around how to convert from the degrees which my PID controller demands to ...
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### Line Follower optimization

I'm working on building a line follower robot and want to optimize its performance. It was suggested that I use a PID algorithm. I read a lot about PID but am confused a bit regarding following: I've ...
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### PID Conundrums for Legged Robots

I am currently working on a legged hexapod which moves around using a tripod gait. I have two sets of code to control the tripod. Set 1: Time based control In this code set, I set the tripod motor ...
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### Can I use Ziegler-Nichols's rules to find PID parameters for a non linear system

I'm trying to use a PID to stabilize a system described from the following difference equation: $$y_{k+1} = a y_k \sqrt{(1-y_k)}~~~ + b y_{k-1} ~+ c u_k$$ Can I use Ziegler-Nichols's rules to find ...
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We are using ArduIMU (V3) as our Quadrotor's inertial measurement unit. (we have a separate board to control all motors, not with ArduIMU itself). As mentioned here , the output rate of this module ...
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### How can I use the Arduino PID library to drive a robot in a straight line?

I would like to create an Arduino based robot with 2 wheels, quadrature encoders on each wheel, a H-bridge driver chip (or motor controller) and a caster. I want to use the PID library to ensure the ...
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### PID tuning to make my balancing robot better [duplicate]

See the video below of my balancing robot. Balancing robot I was having trouble getting it to balance on hard surfaces but finally got it after playing with the PID gains a lot. Previously it was ...
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### What is the actual physical actuated quantity when controlling the position of a servo?

I'm trying to learn about servo control. I have seen that the most generic position control method for servos is PID, where the control input is position error. However, I am not sure about what is ...
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### How is PIV control performed?

I'm considering experimenting with PIV control instead of PID control. Contrary to PID, PIV control has very little explanation on the internet and literature. There is almost a single source of ...
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### I don't understand Integral part of PID controller

I dont understand integral part of PID controller. Let's assume this pseudocode from Wikipedia: ...
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### In PID control, what do the poles and zeros represent?

Whenever I read a text about control (e.g. PID control) it often mentions 'poles' and 'zeros'. What do they mean by that? What physical state does a pole or a zero describe?
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### How can I automatically adjust PID parameters on the fly?

I have a simple servo system that uses a PID controller implemented in an MCU to perform the feedback. However, the properties of the system change dynamically, and so the PID parameters can never be ...
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### Suitable control algorithm for Air Muscle based joint?

I have a joint actuated by an antagonistic pair of Pneumatic Muscles. There are two valves per muscle, one to fill and one to empty each muscle. The joint has an angle sensor, and each muscle also ...
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