Add replicate element to MJCF. Fixes #553

PiperOrigin-RevId: 629393578
Change-Id: Ia1db1b9e47eba8868117b0f7b85edcd0cc1b6d79

model/replicate/README.md

@@ -0,0 +1,27 @@
+# Replicate
+
+Models in this directory provide usage examples of the `<replicate>` meta-element, see
+[documentation](https://mujoco.readthedocs.io/en/stable/XMLreference.html#replicate-r).
+
+The models contain several categories:
+
+1. Constructing static geometries:
+   - cylinder.xml
+   - bowl.xml
+   - helix.xml
+   - container.xml
+
+2. Replicating moving bodies:
+   - particle.xml
+   - bunnies.xml
+   - leaves.xml
+   - stonehenge.xml
+
+3. Replicas that include tendons:
+   - newton_cradle.xml
+   - tendon.xml
+
+4. Replicas with multiple referencing elements:
+   - references.xml
+
+[![Replicate showcase](https://img.youtube.com/vi/5k0_wsIRAFc/0.jpg)](https://www.youtube.com/watch?v=5k0_wsIRAFc)