Inverse Kinematics Solver with SFML

This project demonstrates a simple implementation of an Inverse Kinematics (IK) solver using the SFML (Simple and Fast Multimedia Library) for rendering. The IK solver is used to control a chain of linked segments (often referred to as a "robot arm" or "kinematic chain") to reach a target position in a 2D space.

Table of Contents

• Introduction
• Features
• Dependencies
• Installation
• Usage
• How It Works
• License

Introduction

Inverse Kinematics is a technique used in robotics, animation, and game development to determine the joint parameters (e.g., angles) that will cause a chain of linked segments to reach a desired position. This project implements a simple IK solver using the Cyclic Coordinate Descent (CCD) algorithm, which iteratively adjusts the angles of each joint to minimize the distance between the end effector (the end of the chain) and the target position.

The project uses SFML for rendering the kinematic chain and the target position. The user can click anywhere in the window to set a new target, and the IK solver will adjust the chain to reach the target.

Features

• Interactive Target Setting: Click anywhere in the window to set a new target position.
• Real-Time IK Solver: The IK solver updates the chain's angles in real-time to reach the target.
• Visualization: The kinematic chain and target are visualized using SFML.
• Configurable Parameters: The number of joints, link length, and solver speed can be adjusted in the code.

Dependencies

• SFML: The Simple and Fast Multimedia Library is used for rendering and window management.
  • SFML GitHub
  • SFML Website
• Eigen: A C++ template library for linear algebra, used for vector and matrix operations.
  • Eigen Website

Installation

1. Clone the Repository:

   git clone https://github.com/lazycodebaker/Forward-Kinematics
   cd Forward-Kinematics

2. Install Dependencies:

   • Install SFML:
     • On Ubuntu:

       sudo apt-get install libsfml-dev

     • On macOS (using Homebrew):

       brew install sfml

     • On Windows: Download SFML from the official website and link it to your project.
   • Install Eigen:
     • On Ubuntu:

       sudo apt-get install libeigen3-dev

     • On macOS (using Homebrew):

       brew install eigen

     • On Windows: Download Eigen from the official website and include it in your project.

3. Build the Project:

   • Use CMake or your preferred build system to compile the project.
   • Example using CMake:

     mkdir build
     cd build
     cmake ..
     make

4. Run the Executable:

   • After building, run the executable:

     ./inverse_kinematics_solver

Usage

• Set Target: Click anywhere in the window to set a new target position. The kinematic chain will adjust to reach the target.
• Close Window: Press the close button or Alt+F4 to exit the application.

How It Works

Inverse Kinematics Solver

The IK solver uses the Cyclic Coordinate Descent (CCD) algorithm:

1. Forward Kinematics: The positions of each joint are calculated based on the current angles.
2. Error Calculation: The solver calculates the angle needed to rotate each joint to reduce the distance between the end effector and the target.
3. Angle Adjustment: The angles of each joint are adjusted iteratively until the end effector is close enough to the target (within a specified tolerance).

Rendering

• The kinematic chain is drawn using SFML's sf::Vertex and sf::PrimitiveType::Lines.
• The target is represented as a red circle.

Code Structure

• InverseKinematicsSolver Class: Handles the IK calculations and stores the state of the kinematic chain.
• Main Loop: Handles user input, updates the IK solver, and renders the scene.

License

This project is licensed under the MIT License. See the LICENSE file for details.

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Feel free to contribute to this project by opening issues or submitting pull requests. Enjoy experimenting with inverse kinematics!