Changelog

Changelog#

Version 1.1.1 (February 14, 2026)#

Added#

  • Added reward term visualization to the native viewer (toggle with P).

  • Added DifferentialIKAction for task-space control via damped least-squares IK. Supports weighted position/orientation tracking, soft joint-limit avoidance, and null-space posture regularization. Includes an interactive viser demo (scripts/demos/differential_ik.py).

Fixed#

  • Fixed play.py defaulting to the base rsl-rl OnPolicyRunner instead of MjlabOnPolicyRunner, which caused a TypeError from an unexpected cnn_cfg keyword argument. Contribution by @griffinaddison.

Changed#

  • Removed body_mass, body_inertia, body_pos, and body_quat from FIELD_SPECS in domain randomization. These fields have derived quantities that require set_const to recompute; without that call, randomizing them silently breaks physics.

  • Replaced moviepy with mediapy for video recording. mediapy handles cloud storage paths (GCS, S3) natively.

../_images/native_reward.png

Version 1.1.0 (February 12, 2026)#

Added#

  • Added RGB and depth camera sensors and BVH-accelerated raycasting.

  • Added MetricsManager for logging custom metrics during training.

  • Added terrain visualizer. Contribution by @mktk1117.

../_images/terrain_visualizer.jpg

  • Added many new terrains including HfDiscreteObstaclesTerrainCfg, HfPerlinNoiseTerrainCfg, BoxSteppingStonesTerrainCfg, BoxNarrowBeamsTerrainCfg, BoxRandomStairsTerrainCfg, and more. Added flat patch sampling for heightfield terrains.

  • Added site group visualization to the Viser viewer (Geoms and Sites tabs unified into a single Groups tab).

  • Added env_ids parameter to Entity.write_ctrl_to_sim.

Changed#

  • Upgraded rsl-rl-lib to 4.0.0 and replaced the custom ONNX exporter with rsl-rl’s built-in as_onnx().

  • sim.forward() is now called unconditionally after the decimation loop. See When do I need to call sim.forward()? for details.

  • Unnamed freejoints are now automatically named to prevent KeyError during entity init.

Fixed#

  • Fixed randomize_pd_gains crash with num_envs > 1.

  • Fixed ctrl_ids index error with multiple actuated entities. Reported by @bwrooney82.

  • Fixed Viser viewer rendering textured robots as gray.

  • Fixed Viser plane rendering ignoring MuJoCo size parameter.

  • Fixed HfDiscreteObstaclesTerrainCfg spawn height.

  • Fixed RaycastSensor visualization ignoring the all-envs toggle. Contribution by @oxkitsune.

Version 1.0.0 (January 28, 2026)#

Initial release of mjlab.

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