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Motor control with PID and PWM

Working on adding encoders to my project and could use some resources/help on understanding how to code pulse width modulation (PWM) with Proportional Integral Derivative (PID) to control brushed DC motors. Any help would be wonderful. 


line follower using two linear neurons (controllers) PD for differential and I for speed; both with antiwindup, error filtering and simulated annealing tunning … Read more

PID Tutorials for Line Following

Hey there guys. This post is outdated. Visit http://letsmakerobots.com/node/39972 for the updated tutorial.

Hello LMRians,

In this writeup, I will try to create a tutorial for tuning your robot using PID to follow a line. This tutorial won't go deep down into the details of PID and its applications but will just attempt to show how a robot can be tuned with the PID parameters to follow a line.

Congress Talks about "Trash Robotic Router Platform". My personal project.

I wolud like to share with you, two talks that I have made this year in two national security congresses.

In both talks I present a Router based ROV [Texas Ranger] and a Fonera quadcopter [Atropos] both presented in LMR already:



The aim of "Trash Robotic Router Platform" is pretty the same of many members of this site. Use all you can get lying around in your home!



PID line following

The line following using pid is better. but m unable to understand the procedure to do it on Pic 16 microcontroller...

will someone help with this? first i took values from sensor,subtracted it from correct value,hence i got error value,what to do after that?

Line following
Using a
So after some help from here and pololu I managed to come up with this little freak :D It gets his kP and kD values from BT from phone so I don't have to reprogram … Read more

How to start picking PID gain constants?

I want to implement PID to my balancing robot but I have totally no clue where to start with: picking the gain constants.

My only goal is to make it balance by itself, no time for making it move for now.

With gizduino w/ AtMega328 and GY-52 MPU6050, I was able to use the Kalman Filter to fetch the pitch angle without any problem. I tried to process it with just a simple forward-backward motion without PID, and it falls eventually. Seems like the PID is a necessity, as what I have seen in almost all  references.

Set A Temperature For an Oven Using a Relay
This is my Arduino temperature-ramp PID controller, which is running on a hot plate (up to 325 C) and which shall also be tested on a furnace (up to 650 C).  This … Read more

cr4cX Motor Controller

This blog is about the cr4's motor controller - updated 2012.03.22

Controller features:

  • controls two H bridges;
  • reads, interrupt based, two quadrature encoders;
  • implements PID algorithm for controlling the speed of the motors;
  • synchronize the motors;
  • communicates through Serial and I2C/TWI;
  • monitors the supply voltage;
  • monitors the current through the motors.

Reflow Oven Fan Modified == Good PID loop \0/

16 May 2011

Today I made a slight modification to the toaster oven to see if I can improve the PID loop response.  I was having issues with oscillations no matter how much I adjusted the PID gains.  I suspected this was because I turned the oven on/off in response to the PID output.  This meant the internal oven fan pulled the temperature down below the setpoint a bit every time the oven was turned back on again.  Another side affect is the temperature would overshoot the setpoint a bit once the PID attempted to compensate for the undershoot.

Success! First Test Board Reflowed

15 May 2011 - Update

I have successfully reflow soldered a test PCB.  I got the PID routine tuned a bit and was itching to test out the reflow controller.  So, I applied some solder paster to a old relay controller board I developed and successfully soldered some components to the board.

Below are some pictures of solder paste and components applied to the PCB.

Reflow Controller Update

03 May 2011 - A quick update on the status of my reflow oven.

Reflow Controller

An advanced line follower with quadrature encoders, MicroSD Fat32 recording and more
Using a
This is a bot I built a few years ago when I wanted to start learning robotics. More images here. Its based on the Atmel Mega644P MCU and has an dual H-Bridge … Read more

PID Speed Control

Hello All,

I am new to the site and would like some help with DC motor speed loop control.

A basic proportional  control loop actually works.  The problem I am having is that I need my main power supply to vairy, yet keep the motor speed constant.  The project deals with a helicopter where I need to keep constant speed independent of the battery voltage slowy dropping off.

I have designed and used PID loops for DC gear motor position control, but I am having trouble using similar equations in this application that required speed control and not position control.