📚 Example Programs#

Tip

For models and code, see the MotrixSim Docs repository.

Before running the examples, please refer to 🛠️ Environment Setup to complete the environment setup.

We provide a series of example programs to help you master the use of MotrixSim from scratch.

On all platforms (Linux, Windows, MacOS), you can run any example of interest with:

uv run examples/{example_name}.py

Note

Special note for MacOS (aarch64-apple-darwin) platform:

If the example uses 🎨 Renderer (RenderApp), use:
```
uv run mxpython examples/{example_name}.py
```
If the example does not use RenderApp (physics simulation only), use uv run which is consistent with other platforms

Most examples requiring visual rendering (such as robotic arm control, robot locomotion, etc.) use RenderApp and need uv run mxpython.

Getting Started#

Preview	File	Description
	`empty.py`	Create an empty scene, equivalent to a Hello World example.
	`falling_ball.py`	A ball falls under gravity, demonstrating how to create a `model` and `data`.

API Demonstrations#

Preview	File	Description
	`actuator.py`	Retrieve and configure `actuator` parameters.
	`body.py`	Usage of `body`-related APIs; here, `body` specifically refers to the root world body.
	`joint.py`	Usage of `joint`-related APIs, including reading and writing `dof_position` and `dof_velocity`.
	`link.py`	Usage of `link`-related APIs.
	`model.py`	Usage of `model`-related APIs, including multi-instance scenarios for a single model.
	`options.py`	Configure simulator parameters using `options`.
	`site_and_sensor.py`	Usage of `site` and `sensor`-related APIs.
	`friction.py`	Scene demonstrating friction configuration.
	`parallelsim.py`	Multi-environment parallel simulation.
	`ik.py`	Demonstrates how to use the built-in IK module in MotrixSim for inverse kinematics solving.
	`load_from_str.py`	Load an MJCF model from a string, demonstrating how to create a scene directly from an XML string.
	`combine_msd.py`	Combine multiple MSD models, demonstrating how to use the `Scene.attach()` method to attach multiple models together, supporting transforms and namespace prefixes.
	`geom.py`	Usage of geometry-related APIs, showing how to access and query geometry position, velocity, and other information.
	`hfield.py`	Usage of height field APIs, demonstrating how to access terrain height data and perform statistical analysis.
	`camera_control.py`	Camera control API usage, showing how to enable/disable system and scene cameras, and get camera poses.
	`custom_ui.py`	Usage of custom UI elements, demonstrating how to add buttons and switches for interaction.

Interactive Control#

Preview	File	Description
	`keyboard_car.py`	Control a cart using the keyboard; demonstrates keyboard event handling. Use W to move forward, S to move backward. Turning: A to turn left, D to turn right.
	`mouse_click.py`	Move a ball by clicking on the ground with the mouse; demonstrates mouse event handling.
	`gizmos.py`	Usage of the 3D gizmo drawing system, demonstrating how to draw spheres, cubes, capsules, arrows, grids, and other visualization helpers.

Physics Simulation#

Preview	File	Description
	`gyroscope.py`	Physical simulation of a gyroscope.
	`gyroscope_zero_gravity.py`	Gyroscope in a zero-gravity environment, demonstrating conservation of angular momentum.
	`newton_cradle.py`	Physical simulation of Newton’s cradle.
	`slope.py`	Simulation of a block rolling down a slope.
	`local_arm.py`	A robotic arm composed of simple geometries and `joints`.
	`adhesion.py`	A robotic arm with adhesion actuator.

Robotics Applications#

Preview	File	Description
	`go1.py`	Random motion of the Go1 quadruped robot, demonstrating how to integrate a neural network and use `.onnx` files.
	`robot_locomotion.py`	Go2 quadruped keyboard control example: arrow keys and WASD control walking and turning. Use `uv run examples/robot_locomotion.py --robot go2` to run.
	`robot_locomotion.py`	G1 humanoid keyboard control example: arrow keys and WASD control walking and turning. Use `uv run examples/robot_locomotion.py --robot g1` to run.
	`robot_locomotion.py`	G1 humanoid keyboard control example in an indoor parlour scene: arrow keys and WASD control walking and turning. Use `uv run examples/robot_locomotion.py --robot g1 --scene parlour` to run.
	`robotic_arm.py`	The Stanford robotic arm uses a sequence of movement commands to pick and place a ball.
	`grasp_mx.py`	Grasping and shaking test for the Franka Panda robotic arm, demonstrating how the arm grasps objects and maintains stability. Supports `--object` parameter to select object type (cube/ball/bottle), `--shake` parameter to control shaking, and `--record` parameter to record video.

Rendering & Visualization#

Preview	File	Description
	`render_settings.py`	Rendering settings configuration example, demonstrating how to use `RenderSettings` to configure shadows, screen-space ambient occlusion (SSAO), and other rendering effects.
	`partial_rendering.py`	Selective rendering control in batch rendering, showing how to dynamically control visibility of specific scenes in multi-environment parallel simulation. Press A/D keys to toggle partial scene visibility, Q/E keys for all scenes.
	`share_lights_between_envs.py`	Light sharing optimization between environments, demonstrating how to share lights in parallel simulation to improve performance. Use `--share_lights=False` parameter to disable light sharing.