Environments¶

Mujorax ships with 25 environments from the DeepMind (DM) Control Suite.

This page covers an overview for them listing their respective families and direct links in a table.

Environment families¶

The 25 environments are grouped into 13 families that share physics and bodies. Click a card below for full details on the environments in that family, including the action and observation spaces, rewards, starting state, termination, and a gif preview.

Acrobot (2 variants)

Two-link underactuated pendulum.

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Ball in Cup (1 variant)

Planar ball-and-cup catching task.

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Cartpole (4 variants)

Cart on a track with a free-rotating pole.

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Cheetah (1 variant)

Planar bipedal cheetah-style runner.

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Finger (3 variants)

Two-DoF finger interacting with a free-rotating spinner.

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Fish (1 variant)

3D free-swimming fish in a water-like medium.

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Hopper (2 variants)

Planar one-legged hopper.

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Humanoid (3 variants)

21-DoF humanoid with full upper and lower body actuation.

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Pendulum (1 variant)

Single-link pendulum on a fixed pivot.

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Point Mass (1 variant)

Planar point mass actuated independently in x and y.

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Reacher (2 variants)

Two-link planar arm reaching a randomised target.

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Swimmer (1 variant)

Six-link planar swimmer in a viscous fluid.

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Walker (3 variants)

Planar bipedal walker.

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All environments¶

Canonical ID	Family	Description
`mjx/acrobot_swingup-v0`	Acrobot	Two-link underactuated pendulum; dense reward for swinging the tip to target
`mjx/acrobot_swingup_sparse-v0`	Acrobot	Same as `acrobot_swingup` with a sparse (binary) reward
`mjx/ball_in_cup-v0`	Ball in Cup	Planar ball-and-cup catching task; sparse reward when caught
`mjx/cartpole_balance-v0`	Cartpole	Cart starts near upright; dense reward for keeping the pole upright
`mjx/cartpole_balance_sparse-v0`	Cartpole	Same as `cartpole_balance` with a sparse reward
`mjx/cartpole_swingup-v0`	Cartpole	Cart starts hanging; dense reward for swinging up and balancing
`mjx/cartpole_swingup_sparse-v0`	Cartpole	Same as `cartpole_swingup` with a sparse reward
`mjx/cheetah_run-v0`	Cheetah	Planar bipedal cheetah; dense reward proportional to forward speed
`mjx/finger_spin-v0`	Finger	Two-DoF finger spinning a free body; dense reward for angular velocity
`mjx/finger_turn_easy-v0`	Finger	Two-DoF finger rotating a body to a target with large tolerance
`mjx/finger_turn_hard-v0`	Finger	Same as `finger_turn_easy` with a tighter tolerance
`mjx/fish_swim-v0`	Fish	3D free-swimming fish; dense reward for swimming to a randomised target
`mjx/hopper_hop-v0`	Hopper	One-legged planar hopper; dense reward for forward speed
`mjx/hopper_stand-v0`	Hopper	One-legged hopper; dense reward for standing upright
`mjx/humanoid_run-v0`	Humanoid	21-DoF humanoid; dense reward for matching a running speed
`mjx/humanoid_stand-v0`	Humanoid	21-DoF humanoid; dense reward for standing upright
`mjx/humanoid_walk-v0`	Humanoid	21-DoF humanoid; dense reward for matching a walking speed
`mjx/pendulum_swingup-v0`	Pendulum	Single-link pendulum; dense reward for swinging up and balancing
`mjx/point_mass-v0`	Point Mass	Planar point mass actuated in 2D; dense reward to a randomised target
`mjx/reacher_easy-v0`	Reacher	Two-link planar arm reaching a large target
`mjx/reacher_hard-v0`	Reacher	Same as `reacher_easy` with a smaller target
`mjx/swimmer_swimmer6-v0`	Swimmer	Six-link planar swimmer; dense reward for the head reaching a target
`mjx/walker_run-v0`	Walker	Planar bipedal walker; dense reward for running speed
`mjx/walker_stand-v0`	Walker	Planar bipedal walker; dense reward for standing upright
`mjx/walker_walk-v0`	Walker	Planar bipedal walker; dense reward for walking speed

All physics implementations come from MuJoCo Playground's DM Control Suite []. Mujorax simply adds a thin wrapper that exposes them through Envrax's JaxEnv API; no underlying environment logic is modified from the original.