VirtualHome

VirtualHome is a platform to simulate complex household activities via programs. Key aspect of VirtualHome is that it allows complex interactions with the environment, such as picking up objects, switching on/off appliances, opening appliances, etc. Our simulator can easily be called with a Python API: write the activity as a simple sequence of instructions which then get rendered in VirtualHome. You can choose between different agents and environments, as well as modify environments on the fly. You can also stream different ground-truth such as time-stamped actions, instance/semantic segmentation, and optical flow and depth. The platform allows to simulate multi-agent activities and can serve as an environment to train agents.

Check out more details of the environmnent and platform at virtual-home.org.

What is New

The new version of VirtualHome (VH-Social) is out! Here is what is new.

• VirtualHome now supports multiple agents and a skip_animation mode, to use the environment to train RL models.
• We include OpenAI Gym like environments to train RL agents with VirtualHome. Check out the unity_environment.py class.
• API to add characters in the scene and fixed cameras, and record from those cameras

Contents

1. Overview
2. Set Up
3. Generating Videos/Keyframes
4. Dataset
5. Modify VirtualHome
6. Citation
7. Contributors

Overview

Activities in VirtualHome are represented through two components: programs representing the sequence of actions that compose an activity, and graphs representing a definition of the environment where the activity takes place. Given a program and a graph, the simulator executes the program, generating a video of the activity or a sequence of graphs representing how the environment evolves as the activity takes place. To this end, VirtualHome includes two simulators: the Unity Simulator and Evolving Graph.

Unity Simulator

This simulator is built in Unity and allows generating videos of activities. To use this simulator, you will need to download the appropiate executable and run it with the Python API. You can check a demo of the simulator in demo/unity_demo.ipynb

Evolving Graph

This simulator runs fully in python and allows to generate a sequence of graphs when a program is executed. You can run it in simulation/evolving_graph. Note that some of the objects and actions in this simulator are not supported yet in Unity Simulator.

Set Up

Clone repository and install the dependencies

Note that this code base is based on Python 3

git clone https://github.com/xavierpuigf/virtualhome.git
pip install -r requirements.txt

We also provide a Jupyter notebook with a demo and starting code. If you want to run the demo, install Jupyter and run it on your host. If you are new to Jupyter, see Running the Jupyter Notebook for a walkthrough of how to use this tool.

Download Unity Simulator

Download the VirtualHome UnitySimulator executable and move it under simulation/unity_simulator.

• Download Linux x86-64 version.
• Download Mac OS X version.
• Download Windows version.

Test simulator

To test the simulator in a local machine, double click the executable, select a resolution and screen size and press Play!. Remember to select the option Windowed to make sure the simulator does not take the whole screen. The screenshot below shows our recommended configuration.

Once the simulator is started, run the demo in demo/unity_demo.ipynb.

If you do not have a monitor or want to test the simulator remotely, you can either use Docker or use an X server (find the installation instructions in this medium post). When running the executable with an X server, use -batchmode. For Linux, you would do:

First run the X server on a terminal. You will have to specify which display you want to use, and on which GPUs. By default it will use all the gpus available

sudo python helper_scripts/startx.py $display_num

On a separate terminal, launch the executable

sudo /usr/bin/X $display_num &
DISPLAY=:display_num ./{path_sim}/{exec_file}.x86_64 -batchmode

For Linux, you can also launch the UnityCommunication specifying an executable file. This will directly open the executable on the right sceen. You can do it as follows:

After running the X server, run:

from simulation.unity_simulator import comm_unity
comm = comm_unity.UnityCommunication(file_name=file_name, port={your_port}, x_display={your_display})

It will open an executable and create a communication object to render scripts or simulate actvities. You can open multiple executables at the same time, to train models or generate data using multiple processes.

Docker

You can also run Unity Simulator using Docker. You can find how to set it up here.

Generating Videos and Snapshots

VirtualHome Unity Simulator allows generating videos corresponding to household activities. In addition, it is possible to use Evolving Graph simulator to obtain the environment for each execution step and use UnitySimulator to generate snapshots of the environment at each step.

Generate videos

Open the simulator and run:

cd demo/
python generate_video.py

Generate snapshots

Open the simulator and run:

cd demo/
python generate_snapshots.py

A grid of snapshots for the given script will be generated and saved in demo/snapshot_test.png.

Dataset

We collected a dataset of programs and augmented them with graphs using the Evolving Graph simulator. You can download them here. Once downloaded and unzipped, move the programs into the dataset folder. You can do all this by executing the script

./helper_scripts/download_dataset.sh

The dataset should follow the following structure:

dataset
└── programs_processed_precond_nograb_morepreconds
	|── initstate
	├── withoutconds
	├── executable_programs
	|   ├── TrimmedTestScene7_graph
	|	└── ...
	└── state_list
		├── TrimmedTestScene7_graph
	   	└── ...	

The folders withoutconds and initstate contain the original programs and pre-conditions.

When a script is executed in an environment, the script changes by aligning the original objects with instances in the environment. You can view the resulting script in executable_programs/{environment}/{script_name}.txt.

To view the graph of the environment, and how it changes throughout the script execution of a program, check state_list/{environment}/{script_name}.json.

You can find more details of the programs and environment graphs in dataset/README.md.

Script Augmentation

In Synthesizing Environment-Aware Activities via Activity Sketches, we augment the scripts with two knowledge bases: KB-RealEnv and KB-ExceptonHandler. You can download the augmented scripts in KB-RealEnv and KB-ExceptionHandler.

Here, we provide the code to augment the sripts:

Augment with KB-RealEnv

cd dataset_utils
python augment_dataset_locations.py

Augment with KB-ExceptionHandler

cd dataset_utils
python augment_dataset_exceptions.py

Resources

To do the above generation and augmentation, some valuable resource files are used to set the properties of objects, set the affordance of objects, etc. Check resources/README.md for more details.

Modify VirtualHome

If you would like to contribute to VirtualHome, or modify the simulator for your research needs. Check out the repository with the Unity Source Code. You will need to download the Unity Editor and build your own executable after having made the updates.

Citation

VirtualHome has been used in:

• VirtualHome: Simulating HouseHold Activities via Programs. PDF
  X. Puig*, K. Ra*, M. Boben*, J. Li, T. Wang, S. Fidler, A. Torralba.
  CVPR2018.

• Synthesizing Environment-Aware Activities via Activity Sketches.
  A. Liao*, X. Puig*, M. Boben, A. Torralba, S. Fidler.
  CVPR2019.

• Watch-and-Help: A Challenge for Social Perception and Human-AI Collaboration.
  X. Puig, T. Shu, S. Li, Z. Wang, J. Tenenbaum, S. Fidler, A. Torralba.

If you plan to use the simulator, please consider citing this.

@inproceedings{puig2018virtualhome,
  title={Virtualhome: Simulating household activities via programs},
  author={Puig, Xavier and Ra, Kevin and Boben, Marko and Li, Jiaman and Wang, Tingwu and Fidler, Sanja and Torralba, Antonio},
  booktitle={Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition},
  pages={8494--8502},
  year={2018}
}

@InProceedings{Liao_2019_CVPR,
author = {Liao, Yuan-Hong and Puig, Xavier and Boben, Marko and Torralba, Antonio and Fidler, Sanja},
title = {Synthesizing Environment-Aware Activities via Activity Sketches},
booktitle = {The IEEE Conference on Computer Vision and Pattern Recognition (CVPR)},
month = {June},
year = {2019}
}

@misc{puig2020watchandhelp,
      title={Watch-And-Help: A Challenge for Social Perception and Human-AI Collaboration}, 
      author={Xavier Puig and Tianmin Shu and Shuang Li and Zilin Wang and Joshua B. Tenenbaum and Sanja Fidler and Antonio Torralba},
      year={2020},
      eprint={2010.09890},
      archivePrefix={arXiv},
      primaryClass={cs.AI}
}

Contributors

The VirtualHome API and code has been developed by the following people.

• Marko Boben
• Xavier Puig
• Kevin Ra
• Zilin Wang
• Shuang Li
• Tianmin Shu
• Andrew Liao