Vehicle dynamics using C++: State-space models

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This repository contains the MARSVIN library that contains linear and nonlinear state-space models from vehicles and some useful functions for modelling.

The library depends a lot on CasADi, therefore you need to install CasADI previously or download their binaries. Some CasADi classes are used in some MARSVIN classes.

CasADi Official Page: https://web.casadi.org/

CasADi Github : https://github.com/casadi/casadi

Current implemented classes:

• marsvin::CarNonlinearStateSpace : Nonlinear car state-space model. Modelling included in the class.
  • Inputs: Steering and Braking.
  • States: Longitudinal velocity, lateral velocity and yaw angle.
• marsvin::CarLinearStateSpace : Linear car state-space model. Modelling included in the class.
  • Inputs: Steering and Braking.
  • States: Longitudinal velocity, lateral velocity and yaw angle.
• marsvin::CarNonlinearVxStateSpace : Nonlinear car state-space model assuming constant longitudinal velocity. Modelling included in the class.
  • Inputs: Steering.
  • States: Lateral velocity and yaw angle.
• marsvin::CarLinearVxStateSpace : Linear car state-space model assuming constant longitudinal velocity. Modelling included in the class.
  • Inputs: Steering.
  • States: Lateral velocity and yaw angle.

Addintianlly, one extra class with useful functions:

• marsvin::tools : This class contatins some functions useful for modelling.
  • marsvin::toools::Rz : Calculation of rotation matrix around axis Z.
  • marsvin::toools::ChainRule : Chain rule to calculate df/dt while 'f' depends on 'x', and 'x' depends on 't'.
  • marsvin::toools::rk4 : Next discrete step calculation using Runge-Kutta 4 for state-stace equations.

How to use MARSVIN library?

1) First, install CasADi

I do not trust myself, so I did not build CasADi from source code. I downloaded the already built binaries. I follow the following steps:

1. Download binaries from Oficial CasADi page here. My OS is Linux, also I used Matlab while I get lazy, so I downloaded Matlab binaries for Linux.
2. Unpack the file you downloaded, i.e. casadi-linux-matlabR2014b-v3.5.5.tar.gz file. Note: The version might change.
3. Create a directory in vehicle-dynamics-cpp-casadi called casadi. Note: This directory is included in .gitignore
4. Copy the unpacked files from Point 2 into the directory casadi.

2) Run our example

Do this:

1. Go to vehicle-dynamics-cpp-casadi/examples/01_intro_car_class
2. Run our bash script to run the example. Run this in your Terminal:

bash build-code.sh

Some notes

• The scrips are located in marsvin directory
• The directory marsvin has a CMakeLists.txt that already builds the libmarsvin library.
• The libmarsvin already linked the CasADi libraries.
• In order to use libmarsvin you might need to link it to your target and include marsvin.hpp in your code.