Self-Driving Car Engineer Nanodegree Program
- 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.shor./install-ubuntu.sh. - If you install from source, checkout to commit
e94b6e1, i.e.Some function signatures have changed in v0.14.x. See this PR for more details.git clone https://github.com/uWebSockets/uWebSockets cd uWebSockets git checkout e94b6e1
- Run either
- Simulator. You can download these from the project intro page in the classroom.
There's an experimental patch for windows in this PR
- Clone this repo.
- Make a build directory:
mkdir build && cd build - Compile:
cmake .. && make - Run it:
./pid.
Tips for setting up your environment can be found here
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)
Please (do your best to) stick to Google's C++ style guide.
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.
- 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.
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./
A well written README file can enhance your project and portfolio. Develop your abilities to create professional README files by completing this free course.
The parameter tuning was done with the twiddling and manual tuning afterwards.
The P component increases p_error proportional to the CTE. This has the risk that the car will overshoot and never reach the target trajectory. Is it too high, the car will steadily overshoot and keep on constant CTE which will not reduced by itself. Furthermore, this will also lead to oscallation. Is it set too low the vehicle will never target trajectory because the correction is too small. Moreover, in curves, the vehicle dynamics make it very hard for this compoenent to keep the vehicle on the target trajectory.
In order to reduce the potential oscallation, the D component is introduced that takes the derivate of CTE into account. So, the D part looks at the future and controls the vehicle proactively. Because this is largely required for lane keeping, the D part is set to a very high value. A too low D part doesn't take into account the of the derivate and influence of the P part predominates.
Nevertheless, the car couldn't keep track with a PD controller because a constant offset was set and the vehicle steers in one direction without any correction. Therefore, we sums up all the previous CTE (signed) and call this the I component. With the help of that one, the vehicle smoothens its steering and could correct the constant error.
The P component increases the reaction of the system, but was diminshed after twiddling because the steering reacted not smooth enough.
Moreover, only with tuning the car still leaves the road. But with the adapting the speed to the cte, it was possible. Speed is decreased when the cte goes larger, with an offset of 0.2.