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 engine. ([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)


There are two options available for visualization. Most of the examples included in this repo requires raisimUnity to visualize. You have to run raisimUnity before running the examples.


  • If this doesn’t work on your linux machine, try raisimUnityOpengl, which is a stripped-down version

  • binaries included in the raisimUnity directory

  • easy to use but less features

  • runs as a separate process

  • works well in Linux, Mac and Windows

  • source code available here under the MIT license. Written in C#


  • harder to use but rich in features

  • works well in Linux. Should work in other two major OS’s but not tested

  • easy to customize. Only C++ code

  • source code available here under the MIT license

System Requirements

  • Linux

    • We recommend ubuntu 16.04, 18.04 and 20.04 but RaiSim might work on other distributions

  • Windows 10

    • Visual Studio 2019

  • Mac

    • Latest version. (But probably work on most versions if the cpu supports AVX2)

Example code

Here is an example of an RaiSim application code.

#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).