RaiSim is a physics engine developed by RaiSim Tech Inc. It is designed to provide both the accuracy and speed for simulating robotic systems. However, it is a generic rigid-body simulator and can simulate any rigid body very efficiently.

Why RaiSim?

  • The speed is benchmarked against other popular physics engines. ([1])

  • The accuracy of RaiSim has been demonstrated in a number of papers ([2], [3], [4], [5], [6])

  • Easiest C++ simulation library to learn/use

  • A minimum number of dependencies (only on STL and Eigen)

System Requirements

  • Linux
    • We recommend ubuntu 20.04 or higher but RaiSim might work on other distributions. Works only on a X86 CPU with an AVX2 instruction set (Intel Haswell or higher).

  • Windows 10
    • Visual Studio 2019 or higher. X86 CPU only.

  • Mac
    • Latest version. Requires the AVX2 instruction set. Works on both M1 (Apple ARM) and X86.

Example code

Here is an example of an RaiSim application code. You can visualize it using either raisimUnity or raisimUnreal.

#include “raisim/World.hpp”
#include "raisim/RaisimServer.hpp"

int main() {
  raisim::World world;
  auto anymal = world.addArticulatedSystem(PATH_TO_URDF);
  auto ball = world.addSphere(1, 1);
  auto ground = world.addGround();

  /// launch raisim server for visualization. Can be visualized on raisimUnity
  raisim::RaisimServer server(&world);

  while (1) {


Here is a cmake file to compile above application code.

cmake_minimum_required(VERSION 3.10)
project(raisim_examples LANGUAGES CXX)

find_package(raisim CONFIG REQUIRED)
find_package(Eigen3 REQUIRED)

include_directories (${EIGEN3_INCLUDE_DIRS})

add_executable(APP_NAME ${file_name})
target_link_libraries(APP_NAME PUBLIC raisim::raisim pthread)
target_include_directories(APP_NAME PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include)

A working version can be found here (RAISIM_EXAMPLE).