How to use OpenSim library to create a custom reinforcement learning environment in Matlab?

Hello everyone,

For my research I need to create a custom environment for my RL agent in OpenSim software using the OpenSim API in Matlab. I am wondering whether there is any guidelines to do that. Generally, I am wondering how I can create my own environment using a third-party library in Matlab. Any help is appreciated so much.

Answer 1

[Suraj Kumar]

Hi Masoud,

To create a custom reinforcement learning environment in MATLAB, you can configure MATLAB by adding the OpenSim library using the ‘addpath’ function in MATLAB.

Then you can define the structure of the environment and load the OpenSim model.

import org.opensim.modeling.* 
model = Model('model.osim'); 
state = model.initSystem(); 

Implement the core functions like the step function to update the environment and the reset function to reset the environment to its initial state.Then you can define the custom reinforcement environment using ‘rlFunctionEnv’ function and train the RL agent in the environment.

env = rlFunctionEnv(obsInfo, actInfo, 'stepFcn', 'resetFcn'); 
trainResults = train(agent, env, trainOpts);

To know more about the ‘rlFunctionEnv’ or ‘addpath’ function in MATLAB, you can refer the following documentations:

• https://www.mathworks.com/help/reinforcement-learning/ref/rl.env.rlfunctionenv.html
• https://www.mathworks.com/help/matlab/ref/addpath.html

Hope this will be useful.