diff --git a/mycobot_description/urdf/260_pi/base.dae b/mycobot_description/urdf/260_pi/base.dae
index f27a7095..0110b0af 100644
--- a/mycobot_description/urdf/260_pi/base.dae
+++ b/mycobot_description/urdf/260_pi/base.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-01T07:06:33Z</created>
     <modified>2022-04-01T07:06:33Z</modified>
diff --git a/mycobot_description/urdf/260_pi/link1.dae b/mycobot_description/urdf/260_pi/link1.dae
index 47e0eb48..74011c2b 100644
--- a/mycobot_description/urdf/260_pi/link1.dae
+++ b/mycobot_description/urdf/260_pi/link1.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:08:10Z</created>
     <modified>2022-03-01T03:08:10Z</modified>
diff --git a/mycobot_description/urdf/260_pi/link2.dae b/mycobot_description/urdf/260_pi/link2.dae
index 2230040b..9f9ff39a 100644
--- a/mycobot_description/urdf/260_pi/link2.dae
+++ b/mycobot_description/urdf/260_pi/link2.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:13:26Z</created>
     <modified>2022-03-01T03:13:26Z</modified>
diff --git a/mycobot_description/urdf/260_pi/link3.dae b/mycobot_description/urdf/260_pi/link3.dae
index 548de781..ef24a1b9 100644
--- a/mycobot_description/urdf/260_pi/link3.dae
+++ b/mycobot_description/urdf/260_pi/link3.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:13:43Z</created>
     <modified>2022-03-01T03:13:43Z</modified>
diff --git a/mycobot_description/urdf/260_pi/link4.dae b/mycobot_description/urdf/260_pi/link4.dae
index 6932c478..e7659fae 100644
--- a/mycobot_description/urdf/260_pi/link4.dae
+++ b/mycobot_description/urdf/260_pi/link4.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:10:25Z</created>
     <modified>2022-03-01T03:10:25Z</modified>
diff --git a/mycobot_description/urdf/260_pi/link5.dae b/mycobot_description/urdf/260_pi/link5.dae
index 0cfaf30b..d1455592 100644
--- a/mycobot_description/urdf/260_pi/link5.dae
+++ b/mycobot_description/urdf/260_pi/link5.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:09:55Z</created>
     <modified>2022-03-01T03:09:55Z</modified>
diff --git a/mycobot_description/urdf/260_urdf/base.dae b/mycobot_description/urdf/260_urdf/base.dae
index a5d7f784..478bbb18 100644
--- a/mycobot_description/urdf/260_urdf/base.dae
+++ b/mycobot_description/urdf/260_urdf/base.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:07:26Z</created>
     <modified>2022-03-01T03:07:26Z</modified>
diff --git a/mycobot_description/urdf/260_urdf/link1.dae b/mycobot_description/urdf/260_urdf/link1.dae
index 47e0eb48..74011c2b 100644
--- a/mycobot_description/urdf/260_urdf/link1.dae
+++ b/mycobot_description/urdf/260_urdf/link1.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:08:10Z</created>
     <modified>2022-03-01T03:08:10Z</modified>
diff --git a/mycobot_description/urdf/260_urdf/link2.dae b/mycobot_description/urdf/260_urdf/link2.dae
index 2230040b..9f9ff39a 100644
--- a/mycobot_description/urdf/260_urdf/link2.dae
+++ b/mycobot_description/urdf/260_urdf/link2.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:13:26Z</created>
     <modified>2022-03-01T03:13:26Z</modified>
diff --git a/mycobot_description/urdf/260_urdf/link3.dae b/mycobot_description/urdf/260_urdf/link3.dae
index 548de781..ef24a1b9 100644
--- a/mycobot_description/urdf/260_urdf/link3.dae
+++ b/mycobot_description/urdf/260_urdf/link3.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:13:43Z</created>
     <modified>2022-03-01T03:13:43Z</modified>
diff --git a/mycobot_description/urdf/260_urdf/link4.dae b/mycobot_description/urdf/260_urdf/link4.dae
index 6932c478..e7659fae 100644
--- a/mycobot_description/urdf/260_urdf/link4.dae
+++ b/mycobot_description/urdf/260_urdf/link4.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:10:25Z</created>
     <modified>2022-03-01T03:10:25Z</modified>
diff --git a/mycobot_description/urdf/260_urdf/link5.dae b/mycobot_description/urdf/260_urdf/link5.dae
index 0cfaf30b..d1455592 100644
--- a/mycobot_description/urdf/260_urdf/link5.dae
+++ b/mycobot_description/urdf/260_urdf/link5.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <!-- <author /> -->
+      <!-- <author></author> -->
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <!-- <copyright />
-      <source_data /> -->
+      <!-- <copyright></copyright>
+      <source_data></source_data> -->
     </contributor>
     <created>2022-03-01T03:09:55Z</created>
     <modified>2022-03-01T03:09:55Z</modified>
diff --git a/mycobot_description/urdf/280jn/joint1_jet.dae b/mycobot_description/urdf/280jn/joint1_jet.dae
index e5e4867a..a2eee290 100644
--- a/mycobot_description/urdf/280jn/joint1_jet.dae
+++ b/mycobot_description/urdf/280jn/joint1_jet.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-03-10T03:18:09Z</created>
     <modified>2022-03-10T03:18:09Z</modified>
diff --git a/mycobot_description/urdf/280jn/joint5.dae b/mycobot_description/urdf/280jn/joint5.dae
index cf5d438c..eaf5b270 100644
--- a/mycobot_description/urdf/280jn/joint5.dae
+++ b/mycobot_description/urdf/280jn/joint5.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-04-08T04:22:44Z</created>
     <modified>2021-04-08T04:22:44Z</modified>
diff --git a/mycobot_description/urdf/320_urdf/base.dae b/mycobot_description/urdf/320_urdf/base.dae
index bf1039af..0a4efa8e 100644
--- a/mycobot_description/urdf/320_urdf/base.dae
+++ b/mycobot_description/urdf/320_urdf/base.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-03-09T05:57:29Z</created>
     <modified>2022-03-09T05:57:29Z</modified>
diff --git a/mycobot_description/urdf/320_urdf/gripper_ag.dae b/mycobot_description/urdf/320_urdf/gripper_ag.dae
index 386617b3..5ba4d10b 100644
--- a/mycobot_description/urdf/320_urdf/gripper_ag.dae
+++ b/mycobot_description/urdf/320_urdf/gripper_ag.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-30T10:19:36Z</created>
     <modified>2021-06-30T10:19:36Z</modified>
diff --git a/mycobot_description/urdf/320_urdf/link1.dae b/mycobot_description/urdf/320_urdf/link1.dae
index a0bbc8f7..d64504bc 100644
--- a/mycobot_description/urdf/320_urdf/link1.dae
+++ b/mycobot_description/urdf/320_urdf/link1.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-08T15:34:03Z</created>
     <modified>2021-06-08T15:34:03Z</modified>
diff --git a/mycobot_description/urdf/320_urdf/link2.dae b/mycobot_description/urdf/320_urdf/link2.dae
index 84158eaa..c39a39d2 100644
--- a/mycobot_description/urdf/320_urdf/link2.dae
+++ b/mycobot_description/urdf/320_urdf/link2.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-08T16:19:38Z</created>
     <modified>2021-06-08T16:19:38Z</modified>
diff --git a/mycobot_description/urdf/320_urdf/link3.dae b/mycobot_description/urdf/320_urdf/link3.dae
index fcd82345..5e6dd10a 100644
--- a/mycobot_description/urdf/320_urdf/link3.dae
+++ b/mycobot_description/urdf/320_urdf/link3.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-08T16:19:52Z</created>
     <modified>2021-06-08T16:19:52Z</modified>
diff --git a/mycobot_description/urdf/320_urdf/link4.dae b/mycobot_description/urdf/320_urdf/link4.dae
index 73139180..eb06b610 100644
--- a/mycobot_description/urdf/320_urdf/link4.dae
+++ b/mycobot_description/urdf/320_urdf/link4.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-08T15:34:30Z</created>
     <modified>2021-06-08T15:34:30Z</modified>
diff --git a/mycobot_description/urdf/320_urdf/link5.dae b/mycobot_description/urdf/320_urdf/link5.dae
index b108f0b4..13e3e625 100644
--- a/mycobot_description/urdf/320_urdf/link5.dae
+++ b/mycobot_description/urdf/320_urdf/link5.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.11.21285.13002</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-02-19T12:00:13Z</created>
     <modified>2022-02-19T12:00:13Z</modified>
diff --git a/mycobot_description/urdf/320_urdf/link6.dae b/mycobot_description/urdf/320_urdf/link6.dae
index 45056031..26ef47de 100644
--- a/mycobot_description/urdf/320_urdf/link6.dae
+++ b/mycobot_description/urdf/320_urdf/link6.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-03-09T05:59:06Z</created>
     <modified>2022-03-09T05:59:06Z</modified>
diff --git a/mycobot_description/urdf/600_urdf/base.dae b/mycobot_description/urdf/600_urdf/base.dae
index 277e0738..54f172bc 100644
--- a/mycobot_description/urdf/600_urdf/base.dae
+++ b/mycobot_description/urdf/600_urdf/base.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-22T04:23:09Z</created>
     <modified>2021-06-22T04:23:09Z</modified>
diff --git a/mycobot_description/urdf/600_urdf/link1.dae b/mycobot_description/urdf/600_urdf/link1.dae
index 2570669c..decb2b81 100644
--- a/mycobot_description/urdf/600_urdf/link1.dae
+++ b/mycobot_description/urdf/600_urdf/link1.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-22T04:23:16Z</created>
     <modified>2021-06-22T04:23:16Z</modified>
diff --git a/mycobot_description/urdf/600_urdf/link2.dae b/mycobot_description/urdf/600_urdf/link2.dae
index 840ed430..8a68976d 100644
--- a/mycobot_description/urdf/600_urdf/link2.dae
+++ b/mycobot_description/urdf/600_urdf/link2.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-22T04:23:28Z</created>
     <modified>2021-06-22T04:23:28Z</modified>
diff --git a/mycobot_description/urdf/600_urdf/link3.dae b/mycobot_description/urdf/600_urdf/link3.dae
index a8e9c452..9159382f 100644
--- a/mycobot_description/urdf/600_urdf/link3.dae
+++ b/mycobot_description/urdf/600_urdf/link3.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-22T04:23:34Z</created>
     <modified>2021-06-22T04:23:34Z</modified>
diff --git a/mycobot_description/urdf/600_urdf/link4.dae b/mycobot_description/urdf/600_urdf/link4.dae
index 7660ba69..fc5c4cc3 100644
--- a/mycobot_description/urdf/600_urdf/link4.dae
+++ b/mycobot_description/urdf/600_urdf/link4.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-22T04:23:39Z</created>
     <modified>2021-06-22T04:23:39Z</modified>
diff --git a/mycobot_description/urdf/600_urdf/link5.dae b/mycobot_description/urdf/600_urdf/link5.dae
index ec5d7f10..300d43f0 100644
--- a/mycobot_description/urdf/600_urdf/link5.dae
+++ b/mycobot_description/urdf/600_urdf/link5.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-22T04:23:43Z</created>
     <modified>2021-06-22T04:23:43Z</modified>
diff --git a/mycobot_description/urdf/600_urdf/link6.dae b/mycobot_description/urdf/600_urdf/link6.dae
index 519e4556..f1345399 100644
--- a/mycobot_description/urdf/600_urdf/link6.dae
+++ b/mycobot_description/urdf/600_urdf/link6.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-06-22T04:23:48Z</created>
     <modified>2021-06-22T04:23:48Z</modified>
diff --git a/mycobot_description/urdf/mecharm/base.dae b/mycobot_description/urdf/mecharm/base.dae
index a5c27a5d..d616f17b 100644
--- a/mycobot_description/urdf/mecharm/base.dae
+++ b/mycobot_description/urdf/mecharm/base.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-06-20T07:54:27Z</created>
     <modified>2022-06-20T07:54:27Z</modified>
diff --git a/mycobot_description/urdf/mecharm/link1.dae b/mycobot_description/urdf/mecharm/link1.dae
index 6a7137ac..6cbe26bb 100644
--- a/mycobot_description/urdf/mecharm/link1.dae
+++ b/mycobot_description/urdf/mecharm/link1.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:08:10Z</created>
     <modified>2022-04-22T03:08:10Z</modified>
diff --git a/mycobot_description/urdf/mecharm/link2.dae b/mycobot_description/urdf/mecharm/link2.dae
index 1dccff65..5fe93725 100644
--- a/mycobot_description/urdf/mecharm/link2.dae
+++ b/mycobot_description/urdf/mecharm/link2.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:08:47Z</created>
     <modified>2022-04-22T03:08:47Z</modified>
diff --git a/mycobot_description/urdf/mecharm/link3.dae b/mycobot_description/urdf/mecharm/link3.dae
index 4698c96d..f6255b1a 100644
--- a/mycobot_description/urdf/mecharm/link3.dae
+++ b/mycobot_description/urdf/mecharm/link3.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:09:58Z</created>
     <modified>2022-04-22T03:09:58Z</modified>
diff --git a/mycobot_description/urdf/mecharm/link4.dae b/mycobot_description/urdf/mecharm/link4.dae
index 07e13215..a7f81e9b 100644
--- a/mycobot_description/urdf/mecharm/link4.dae
+++ b/mycobot_description/urdf/mecharm/link4.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:10:19Z</created>
     <modified>2022-04-22T03:10:19Z</modified>
diff --git a/mycobot_description/urdf/mecharm/link5.dae b/mycobot_description/urdf/mecharm/link5.dae
index dec8390a..9854ccf9 100644
--- a/mycobot_description/urdf/mecharm/link5.dae
+++ b/mycobot_description/urdf/mecharm/link5.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:10:32Z</created>
     <modified>2022-04-22T03:10:32Z</modified>
diff --git a/mycobot_description/urdf/mecharm/link6.dae b/mycobot_description/urdf/mecharm/link6.dae
index e58c0158..be56b56e 100644
--- a/mycobot_description/urdf/mecharm/link6.dae
+++ b/mycobot_description/urdf/mecharm/link6.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:15:32Z</created>
     <modified>2022-04-22T03:15:32Z</modified>
diff --git a/mycobot_description/urdf/mecharm_pi/base.dae b/mycobot_description/urdf/mecharm_pi/base.dae
index f188ee33..64f3a4e0 100644
--- a/mycobot_description/urdf/mecharm_pi/base.dae
+++ b/mycobot_description/urdf/mecharm_pi/base.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:05:56Z</created>
     <modified>2022-04-22T03:05:56Z</modified>
diff --git a/mycobot_description/urdf/mecharm_pi/link1.dae b/mycobot_description/urdf/mecharm_pi/link1.dae
index 6a7137ac..6cbe26bb 100644
--- a/mycobot_description/urdf/mecharm_pi/link1.dae
+++ b/mycobot_description/urdf/mecharm_pi/link1.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:08:10Z</created>
     <modified>2022-04-22T03:08:10Z</modified>
diff --git a/mycobot_description/urdf/mecharm_pi/link2.dae b/mycobot_description/urdf/mecharm_pi/link2.dae
index 1dccff65..5fe93725 100644
--- a/mycobot_description/urdf/mecharm_pi/link2.dae
+++ b/mycobot_description/urdf/mecharm_pi/link2.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:08:47Z</created>
     <modified>2022-04-22T03:08:47Z</modified>
diff --git a/mycobot_description/urdf/mecharm_pi/link3.dae b/mycobot_description/urdf/mecharm_pi/link3.dae
index 4698c96d..f6255b1a 100644
--- a/mycobot_description/urdf/mecharm_pi/link3.dae
+++ b/mycobot_description/urdf/mecharm_pi/link3.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:09:58Z</created>
     <modified>2022-04-22T03:09:58Z</modified>
diff --git a/mycobot_description/urdf/mecharm_pi/link4.dae b/mycobot_description/urdf/mecharm_pi/link4.dae
index 07e13215..a7f81e9b 100644
--- a/mycobot_description/urdf/mecharm_pi/link4.dae
+++ b/mycobot_description/urdf/mecharm_pi/link4.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:10:19Z</created>
     <modified>2022-04-22T03:10:19Z</modified>
diff --git a/mycobot_description/urdf/mecharm_pi/link5.dae b/mycobot_description/urdf/mecharm_pi/link5.dae
index dec8390a..9854ccf9 100644
--- a/mycobot_description/urdf/mecharm_pi/link5.dae
+++ b/mycobot_description/urdf/mecharm_pi/link5.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:10:32Z</created>
     <modified>2022-04-22T03:10:32Z</modified>
diff --git a/mycobot_description/urdf/mecharm_pi/link6.dae b/mycobot_description/urdf/mecharm_pi/link6.dae
index e58c0158..be56b56e 100644
--- a/mycobot_description/urdf/mecharm_pi/link6.dae
+++ b/mycobot_description/urdf/mecharm_pi/link6.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros 7.5.21082.11001</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2022-04-22T03:15:32Z</created>
     <modified>2022-04-22T03:15:32Z</modified>
diff --git a/mycobot_description/urdf/seeed/joint1_seeed.dae b/mycobot_description/urdf/seeed/joint1_seeed.dae
index d2839edd..95765726 100644
--- a/mycobot_description/urdf/seeed/joint1_seeed.dae
+++ b/mycobot_description/urdf/seeed/joint1_seeed.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-11-25T06:53:25Z</created>
     <modified>2021-11-25T06:53:25Z</modified>
diff --git a/mycobot_description/urdf/seeed/joint5.dae b/mycobot_description/urdf/seeed/joint5.dae
index cf5d438c..eaf5b270 100644
--- a/mycobot_description/urdf/seeed/joint5.dae
+++ b/mycobot_description/urdf/seeed/joint5.dae
@@ -2,11 +2,11 @@
 <COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
   <asset>
     <contributor>
-      <author />
+      <author></author>
       <authoring_tool>Rhinoceros</authoring_tool>
       <comments>Output from Rhinoceros COLLADA Exporter</comments>
-      <copyright />
-      <source_data />
+      <copyright></copyright>
+      <source_data></source_data>
     </contributor>
     <created>2021-04-08T04:22:44Z</created>
     <modified>2021-04-08T04:22:44Z</modified>