Training & Deploying HOVER Policy

This tutorial shows you an example of how to train and deploy HOVER which is a whole-body control (WBC) policy for humanoid robots in the Isaac Lab simulation environment. It uses the HOVER repository, which provides an Isaac Lab extension for training neural whole-body control policy for humanoids, as described in the HOVER Paper and OMNIH2O Paper papers. For video demonstrations and more details about the project, please visit the HOVER Project Website and the OMNIH2O Project Website.

Installation

1. Install Isaac Lab following the instructions in the Isaac Lab Installation Guide.

2. Define the following environment variable to specify the path to your Isaac Lab installation:

# Set the ISAACLAB_PATH environment variable to point to your Isaac Lab installation directory
export ISAACLAB_PATH=<your_isaac_lab_path>

3. Clone the HOVER repository and its submodules in your workspace.

git clone --recurse-submodules https://github.com/NVlabs/HOVER.git

4. Install the dependencies.

cd HOVER
./install_deps.sh

Training the Policy

Dataset

Refer to the HOVER Dataset repository for the steps to obtain and process data for training the policy.

Training the teacher policy

Execute the following command from the HOVER directory to train the teacher policy.

${ISAACLAB_PATH:?}/isaaclab.sh -p scripts/rsl_rl/train_teacher_policy.py \
    --num_envs 1024 \
    --reference_motion_path neural_wbc/data/data/motions/stable_punch.pkl \
    --headless

The teacher policy is trained for 10000000 iterations, or until the user interrupts the training. The resulting checkpoint is stored in neural_wbc/data/data/policy/h1:teacher/ and the filename is model_<iteration_number>.pt.

Training the student policy

Execute the following command from the HOVER directory to train the student policy using teacher policy checkpoint.

${ISAACLAB_PATH:?}/isaaclab.sh -p scripts/rsl_rl/train_student_policy.py \
    --num_envs 1024 \
    --reference_motion_path neural_wbc/data/data/motions/stable_punch.pkl \
    --teacher_policy.resume_path neural_wbc/data/data/policy/h1:teacher \
    --teacher_policy.checkpoint model_<iteration_number>.pt \
    --headless

This assumes that you have already trained the teacher policy as there is no provided teacher policy in the repo.

Please refer to these sections on the HOVER repository for more details about training configurations:

• General Remarks for Training
• Generalist vs Specialist Policy

Testing the trained policy

Play teacher policy

Execute the following command from the HOVER directory to play the trained teacher policy checkpoint.

${ISAACLAB_PATH:?}/isaaclab.sh -p scripts/rsl_rl/play.py \
    --num_envs 10 \
    --reference_motion_path neural_wbc/data/data/motions/stable_punch.pkl \
    --teacher_policy.resume_path neural_wbc/data/data/policy/h1:teacher \
    --teacher_policy.checkpoint model_<iteration_number>.pt

Play student policy

Execute the following command from the HOVER directory to play the trained student policy checkpoint.

${ISAACLAB_PATH:?}/isaaclab.sh -p scripts/rsl_rl/play.py \
    --num_envs 10 \
    --reference_motion_path neural_wbc/data/data/motions/stable_punch.pkl \
    --student_player \
    --student_path neural_wbc/data/data/policy/h1:student \
    --student_checkpoint model_<iteration_number>.pt

Evaluate the trained policy

Evaluate the trained policy checkpoint in the Isaac Lab environment. The evaluation iterates through all the reference motions included in the dataset specified by the --reference_motion_path option and exits when all motions are evaluated. Randomization is turned off during evaluation.

Refer to the HOVER Evaluation repository for more details about the evaluation pipeline and the metrics used.

The evaluation script, scripts/rsl_rl/eval.py, uses the same arguments as the play script, scripts/rsl_rl/play.py. You can use it for both teacher and student policies.

${ISAACLAB_PATH}/isaaclab.sh -p scripts/rsl_rl/eval.py \
--num_envs 10 \
--teacher_policy.resume_path neural_wbc/data/data/policy/h1:teacher \
--teacher_policy.checkpoint model_<iteration_number>.pt

Validation of the policy

The trained policy in Isaac Lab can be validated in another simulation environment or on the real robot.

Sim-to-Sim Validation

Use the provided Mujoco Environment for conducting sim-to-sim validation of the trained policy. To run the evaluation of Sim2Sim,

${ISAACLAB_PATH:?}/isaaclab.sh -p neural_wbc/inference_env/scripts/eval.py \
    --num_envs 1 \
    --headless \
    --student_path neural_wbc/data/data/policy/h1:student/ \
    --student_checkpoint model_<iteration_number>.pt

Please be aware that the mujoco_wrapper only supports one environment at a time. For reference, it will take up to 5h to evaluate 8k reference motions. The inference_env is designed for maximum versatility.

Sim-to-Real Deployment

For sim-to-real deployment, we provide a Hardware Environment for Unitree H1 Robot. Detailed steps of setting up a Sim-to-Real deployment workflow is explained at README of Sim2Real deployment.

To deploy the trained policy on the H1 robot,

${ISAACLAB_PATH:?}/isaaclab.sh -p neural_wbc/inference_env/scripts/s2r_player.py \
    --student_path neural_wbc/data/data/policy/h1:student/ \
    --student_checkpoint model_<iteration_number>.pt \
    --reference_motion_path neural_wbc/data/data/motions/<motion_name>.pkl \
    --robot unitree_h1 \
    --max_iterations 5000 \
    --num_envs 1 \
    --headless