diff --git a/arm_1dof/demo_human_col/skeleton.sdf b/arm_1dof/demo_human_col/skeleton.sdf
index 78faa26..c4c8061 100644
--- a/arm_1dof/demo_human_col/skeleton.sdf
+++ b/arm_1dof/demo_human_col/skeleton.sdf
@@ -299,7 +299,7 @@
             <parent>world</parent>
             <child>skeleton</child>
         </joint> -->
-        <joint name="shoulder_joint" type="revolute">
+        <joint name="shoulder_joint" type="fixed">
             <parent>skeleton</parent>
             <child>upper_arm</child>
             <pose>-0.0002625510096549988 0.1382385492324829 0.0034110769629478455 5.479091100824007e-07 -4.2146872658577195e-08 -1.570796251296997</pose>
@@ -350,7 +350,7 @@
                 </dynamics>
             </axis>
         </joint>
-        <joint name="proximal_joint" type="revolute">
+        <joint name="proximal_joint" type="fixed">
             <parent>hand</parent>
             <child>proximal</child>
             <pose>-0.006849215365946293 0.01723306067287922 -0.006170365028083324 0.18470512330532074 -0.15172354876995087 -1.2801685333251953</pose>
@@ -419,7 +419,7 @@
                 </dynamics>
             </axis>
         </joint>
-        <joint name="middle_joint" type="revolute">
+        <joint name="middle_joint" type="fixed">
             <parent>proximal</parent>
             <child>middle</child>
             <pose>-0.005126905627548695 0.008538579568266869 -0.001958192093297839 0.18470518290996552 -0.1517234593629837 -1.4588162899017334</pose>
@@ -436,7 +436,7 @@
                 </dynamics>
             </axis>
         </joint>
-        <joint name="distal_joint" type="revolute">
+        <joint name="distal_joint" type="fixed">
             <parent>middle</parent>
             <child>distal</child>
             <pose>-0.0028767052572220564 0.0012630047276616096 -0.0008793922024779022 0.18470518290996552 -0.1517234444618225 -1.4789243936538696</pose>
diff --git a/arm_1dof/demo_human_col/skeleton.urdf b/arm_1dof/demo_human_col/skeleton.urdf
index 8bb2f20..7a6e5ca 100644
--- a/arm_1dof/demo_human_col/skeleton.urdf
+++ b/arm_1dof/demo_human_col/skeleton.urdf
@@ -1,6 +1,6 @@
 <?xml version="1.0" ?>
 <robot name="skeleton">
-  <joint name="skeleton__shoulder_joint" type="revolute">
+  <joint name="skeleton__shoulder_joint" type="fixed">
     <parent link="skeleton__skeleton"/>
     <child link="skeleton__upper_arm"/>
     <origin xyz="-0.01754 -0.17     1.793" rpy="1.59151 1.57079 0.02072"/>
@@ -21,7 +21,7 @@
     <axis xyz="0 0 1"/>
     <limit lower="0.0" upper="1.5707963705062866" effort="0.0" velocity="0.0"/>
   </joint>
-  <joint name="skeleton__proximal_joint" type="revolute">
+  <joint name="skeleton__proximal_joint" type="fixed">
     <parent link="skeleton__hand"/>
     <child link="skeleton__proximal"/>
     <origin xyz="0.0941  0.002   0.00495" rpy="0.1847  -0.15172  0.24123"/>
@@ -49,14 +49,14 @@
     <axis xyz="0 0 1"/>
     <limit lower="0.0" upper="1.5707963705062866" effort="0.0" velocity="0.0"/>
   </joint>
-  <joint name="skeleton__middle_joint" type="revolute">
+  <joint name="skeleton__middle_joint" type="fixed">
     <parent link="skeleton__proximal"/>
     <child link="skeleton__middle"/>
     <origin xyz="0.04285 0      0" rpy="0 0 0"/>
     <axis xyz="0 0 1"/>
     <limit lower="0.0" upper="1.5707963705062866" effort="0.0" velocity="0.0"/>
   </joint>
-  <joint name="skeleton__distal_joint" type="revolute">
+  <joint name="skeleton__distal_joint" type="fixed">
     <parent link="skeleton__middle"/>
     <child link="skeleton__distal"/>
     <origin xyz="0.02734  0.00572 -0.00241" rpy="0 0 0"/>