cartpole-physics

C# source code for simulation of the cart and pole balancing task.

For details of this task, including derivations of the equations of motion, see the following technical research paper:

Equations of Motion for the Cart and Pole Control Task

The source code in this reposistory can be considered to be supplementary material for that paper.

Repository Overview

This repository contains C# source code (src folder) for the cart-pole balancing task, and some R/ggplot2 scripts (r-ggplot2 folder) for creating plots for the above linked research paper.

Source Code Overview

The source is written in C# and targets .NET Standard 2.1 and .NET Core 3.1. However, the physics/maths code should be easy to port to any other language.

Visual Studio 2019 was used to author the code, and thus the source code is structured as a containing Visual Studio 'solution' (CartPolePhysics.sln), with three projects within it. These are:

CartPolePhysics

This project contains the maths/physics source code. The project targets .NET Standard 2.1 as this provides a MathF class that is used for the code that operates with single precision floating point variables, most notably MathF.Sin() and Cos().

• Double

  • CartSinglePoleEquations.cs
    • Contains the equations of motion for the cart-pole model, giving the horizontal acceleration of the cart and the angular acceleration of the pole for a given model state and external force f (a horizontal force pushing the cart left or right).
  • CartSinglePolePhysics.cs
    • Contains an instance of CartSinglePoleEquations, and applies Euler's method to update the model state from one timestep to the next. This is also the base class for CartSinglePolePhysicsRK2 and CartSinglePolePhysicsRK4.
  • CartSinglePolePhysicsRK2.cs
    • Contains an instance of CartSinglePoleEquations, and applies the standard second-order Runge-Kutta method to update the model state from one timestep to the next.
  • CartSinglePolePhysicsRK4.cs
    • Contains an instance of CartSinglePoleEquations, and applies the classic fourth-order Runge-Kutta method to update the model state from one timestep to the next.

• Single

  • The classes in this folder/namespace mirror exactly those of the 'Double' folder, but provide physics calculation based on single precision floating point maths.

CartPoleConsole

A small console app that can be used to run a simulation and save a CSV fiel containing the model state at each timestep. These CSV files can then be used to make plots, e.g. with R and ggplot2.

CartPoleWinForms

A small Windows Forms app that targets .NET Core 3.1. The ability to run Winforms apps in .NET Core is a recent addition to that platform, and this is only possible when the app is running on Microsoft Windows.

This app runs a simulation and shows a graph on screen of pole angle, cart position, and pole angular velocity over time.