Update armature, damping, friction in FR3 model.

quagla · copybara-github · commit cd7fc51b704c · 2025-04-25T02:19:32.000-07:00
PiperOrigin-RevId: 751330639
Change-Id: I5c1c429ae1e2380511acccdb7db3240bd82e0033
diff --git a/franka_fr3/README.md b/franka_fr3/README.md
@@ -3,6 +3,10 @@
 > [!IMPORTANT]
 > Requires MuJoCo 3.1.3 or later.
 
+## Changelog
+
+- 04/24/2025: The `armature`, `damping`, and `frictionloss` parameters were identified in torque control.
+
 ## Overview
 
 This package contains a simplified robot description (MJCF) of the [Franka Research 3](https://franka.de/research) (aka FR3) developed by [Franka Robotics](https://franka.de/company) (formerly Franka Emika). It is derived from the [publicly available URDF description](https://github.com/frankaemika/franka_description).
diff --git a/franka_fr3/fr3.xml b/franka_fr3/fr3.xml
@@ -5,7 +5,8 @@
 
   <default>
     <default class="fr3">
-      <joint armature="0.1" damping="1"/>
+      <!-- Overwritten in joints 5, 6, and 7. -->
+      <joint damping="0.21" armature="0.195" frictionloss="1.137"/>
       <position inheritrange="1"/>
       <default class="visual">
         <geom type="mesh" group="2" contype="0" conaffinity="0"/>
@@ -105,15 +106,17 @@
                 <body name="fr3_link5" pos="-0.0825 0.384 0" quat="1 -1 0 0">
                   <inertial pos="-0.00160396 0.0292536 -0.0972966" quat="0.919031 0.125604 0.0751531 -0.366003"
                     mass="2.32712" diaginertia="0.0579335 0.0449144 0.0130634"/>
-                  <joint name="fr3_joint5" axis="0 0 1" range="-2.8065 2.8065" actuatorfrcrange="-12 12"/>
+                  <joint name="fr3_joint5" axis="0 0 1" range="-2.8065 2.8065" actuatorfrcrange="-12 12"
+                    armature="0.074" frictionloss="0.763"/>
                   <geom mesh="link5_0" material="white" class="visual"/>
                   <geom mesh="link5_1" material="white" class="visual"/>
                   <geom mesh="link5_2" material="black" class="visual"/>
                   <geom name="fr3_link5_collision" class="collision" mesh="link5_coll"/>
                   <body name="fr3_link6" quat="1 1 0 0">
                     <inertial pos="0.0597131 -0.0410295 -0.0101693" quat="0.621301 0.552665 0.510011 0.220081"
                       mass="1.81704" diaginertia="0.0175039 0.0161123 0.00193529"/>
-                    <joint name="fr3_joint6" axis="0 0 1" range="0.5445 4.5169" actuatorfrcrange="-12 12"/>
+                    <joint name="fr3_joint6" axis="0 0 1" range="0.5445 4.5169" actuatorfrcrange="-12 12"
+                      armature="0.074" frictionloss="0.44"/>
                     <geom mesh="link6_0" material="button_green" class="visual"/>
                     <geom mesh="link6_1" material="white" class="visual"/>
                     <geom mesh="link6_2" material="white" class="visual"/>
@@ -126,7 +129,8 @@
                     <body name="fr3_link7" pos="0.088 0 0" quat="1 1 0 0">
                       <inertial pos="0.00452258 0.00862619 -0.0161633" quat="0.727579 0.0978688 -0.24906 0.63168"
                         mass="0.627143" diaginertia="0.000223836 0.000223642 5.64132e-07"/>
-                      <joint name="fr3_joint7" axis="0 0 1" range="-3.0159 3.0159" actuatorfrcrange="-12 12"/>
+                      <joint name="fr3_joint7" axis="0 0 1" range="-3.0159 3.0159" actuatorfrcrange="-12 12"
+                        armature="0.074" frictionloss="0.248"/>
                       <geom mesh="link7_0" material="black" class="visual"/>
                       <geom mesh="link7_1" material="white" class="visual"/>
                       <geom mesh="link7_2" material="white" class="visual"/>
