CarND-Controls-PID

Self-Driving Car Engineer Nanodegree Program

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Main goal of the project is to implement PID control for steering vehicle on the track in simulation.

PID control is the basic technic in automatic control of some parameters. The main idea of the method is that we have 3 parameters which are affect out output parameter (here is steering angle): (P)roportional, linear relation with the parameter error, P tryes to reduce error as fast as possible,so it is usually drive to overshooting and oscilation.
(I)ntegral, is related to the average value of the parameter error, I tryes to reduce bias of the parameter, if it is. (D)ifferential, linear relation with the rate of change of the parameter error, D tryes to prevent overshooting by reducing correction value of the parameter if error is small enough.

Tuning final hyperparameters. First of all I tune them by hands because car wasn't able to go through the track. I stated by increasing the P till the oscilations and the I started adding D component to reduce occilations. So then Car can go atleast one lap I turned on the tweddling algorithm.

I try different coefficiets (from 0.5 to 0.1) for tuning parameters (line 30-31 in PID.cpp), more stability in convergence was achived with 0.1. Also I try different number of steps (lines 36-27 in PID.cpp) for error evaluating and the best result was achived with 1100 steps in sum that is near the lenth of one lap.

Final parameters are P = 0.117, I = 0.001, D = 1.521.

Here is video control with these parameters.

Dependencies

• cmake >= 3.5
• All OSes: click here for installation instructions
• make >= 4.1(mac, linux), 3.81(Windows)
  • Linux: make is installed by default on most Linux distros
  • Mac: install Xcode command line tools to get make
  • Windows: Click here for installation instructions
• gcc/g++ >= 5.4
  • Linux: gcc / g++ is installed by default on most Linux distros
  • Mac: same deal as make - [install Xcode command line tools]((https://developer.apple.com/xcode/features/)
  • Windows: recommend using MinGW
• uWebSockets
  • Run either ./install-mac.sh or ./install-ubuntu.sh.
  • If you install from source, checkout to commit e94b6e1, i.e.

    git clone https://github.com/uWebSockets/uWebSockets 
    cd uWebSockets
    git checkout e94b6e1
    

    Some function signatures have changed in v0.14.x. See this PR for more details.
• Simulator. You can download these from the project intro page in the classroom.

Fellow students have put together a guide to Windows set-up for the project here if the environment you have set up for the Sensor Fusion projects does not work for this project. There's also an experimental patch for windows in this PR.

Basic Build Instructions

1. Clone this repo.
2. Make a build directory: mkdir build && cd build
3. Compile: cmake .. && make
4. Run it: ./pid.

Tips for setting up your environment can be found here

Editor Settings

We've purposefully kept editor configuration files out of this repo in order to keep it as simple and environment agnostic as possible. However, we recommend using the following settings:

• indent using spaces
• set tab width to 2 spaces (keeps the matrices in source code aligned)

Code Style

Please (do your best to) stick to Google's C++ style guide.

Project Instructions and Rubric

Note: regardless of the changes you make, your project must be buildable using cmake and make!

More information is only accessible by people who are already enrolled in Term 2 of CarND. If you are enrolled, see the project page for instructions and the project rubric.

Hints!

• You don't have to follow this directory structure, but if you do, your work will span all of the .cpp files here. Keep an eye out for TODOs.

Call for IDE Profiles Pull Requests

Help your fellow students!

We decided to create Makefiles with cmake to keep this project as platform agnostic as possible. Similarly, we omitted IDE profiles in order to we ensure that students don't feel pressured to use one IDE or another.

However! I'd love to help people get up and running with their IDEs of choice. If you've created a profile for an IDE that you think other students would appreciate, we'd love to have you add the requisite profile files and instructions to ide_profiles/. For example if you wanted to add a VS Code profile, you'd add:

• /ide_profiles/vscode/.vscode
• /ide_profiles/vscode/README.md

The README should explain what the profile does, how to take advantage of it, and how to install it.

Frankly, I've never been involved in a project with multiple IDE profiles before. I believe the best way to handle this would be to keep them out of the repo root to avoid clutter. My expectation is that most profiles will include instructions to copy files to a new location to get picked up by the IDE, but that's just a guess.

One last note here: regardless of the IDE used, every submitted project must still be compilable with cmake and make./

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