diff --git a/CMakeLists.txt b/CMakeLists.txt
index b8e97d8244f92002fce302a744dbaefb993e74ee..9e86d1c45ca36f882fc83d1df779ed0bf85c9818 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -83,6 +83,7 @@ SET(${PROJECT_NAME}_MATH_HEADERS
 
 SET(${PROJECT_NAME}_TOOLS_HEADERS
   tools/timer.hpp
+  tools/string-generator.hpp
   )
 
 SET(${PROJECT_NAME}_SPATIAL_HEADERS
diff --git a/src/multibody/model.hpp b/src/multibody/model.hpp
index 24d7f8fdc2510b1f38dc362b513b0e03ccbdf793..e43c03d7f5180275198771fca576dcb0febe37a3 100644
--- a/src/multibody/model.hpp
+++ b/src/multibody/model.hpp
@@ -27,6 +27,7 @@
 #include "pinocchio/spatial/inertia.hpp"
 #include "pinocchio/spatial/frame.hpp"
 #include "pinocchio/multibody/joint/joint-variant.hpp"
+#include "pinocchio/tools/string-generator.hpp"
 #include <iostream>
 
 EIGEN_DEFINE_STL_VECTOR_SPECIALIZATION(se3::SE3)
diff --git a/src/multibody/model.hxx b/src/multibody/model.hxx
index 4e154279bc5d65290ad61094e55b8cfb4dabaf7f..16d182119fcf0dd11c2dda64a39dd725ced42b77 100644
--- a/src/multibody/model.hxx
+++ b/src/multibody/model.hxx
@@ -43,18 +43,7 @@ namespace se3
     return os;
   }
 
-  inline std::string random (const int len)
-  {
-    std::string res;
-    static const char alphanum[] =
-        "0123456789"
-        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-        "abcdefghijklmnopqrstuvwxyz";
-
-    for (int i=0; i<len;++i)
-      res += alphanum[((size_t)std::rand() % (sizeof(alphanum) - 1))];
-    return res;
-  }
+  
 
   template<typename D>
   Model::Index Model::addBody (Index parent, const JointModelBase<D> & j, const SE3 & placement,
diff --git a/src/spatial/frame.hpp b/src/spatial/frame.hpp
index ee491886679f80fe563a936b2901aa379c6d9a66..45584baf10369b17e9d5e75c54b34702a2b62802 100644
--- a/src/spatial/frame.hpp
+++ b/src/spatial/frame.hpp
@@ -23,6 +23,7 @@
 #include "pinocchio/spatial/force.hpp"
 #include "pinocchio/spatial/motion.hpp"
 #include "pinocchio/spatial/inertia.hpp"
+#include "pinocchio/tools/string-generator.hpp"
 #include <iostream>
 
 namespace se3
@@ -31,7 +32,7 @@ struct Frame
 {
   typedef std::size_t Index;
   
-  Frame() : name(), parent_id(), frame_placement()
+  Frame() : name(random(8)), parent_id(), frame_placement()
   {
 
   }
diff --git a/src/tools/string-generator.hpp b/src/tools/string-generator.hpp
new file mode 100644
index 0000000000000000000000000000000000000000..8930cc739184d38f1952005fffe64935115963b5
--- /dev/null
+++ b/src/tools/string-generator.hpp
@@ -0,0 +1,39 @@
+//
+// Copyright (c) 2016 CNRS
+//
+// This file is part of Pinocchio
+// Pinocchio is free software: you can redistribute it
+// and/or modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation, either version
+// 3 of the License, or (at your option) any later version.
+//
+// Pinocchio is distributed in the hope that it will be
+// useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+// of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Lesser Public License for more details. You should have
+// received a copy of the GNU Lesser General Public License along with
+// Pinocchio If not, see
+// <http://www.gnu.org/licenses/>.
+
+#ifndef __se3_string_generator_hpp__
+#define __se3_string_generator_hpp__
+
+#include <iostream>
+namespace se3
+{
+
+inline std::string random (const int len)
+  {
+    std::string res;
+    static const char alphanum[] =
+        "0123456789"
+        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+        "abcdefghijklmnopqrstuvwxyz";
+
+    for (int i=0; i<len;++i)
+      res += alphanum[((size_t)std::rand() % (sizeof(alphanum) - 1))];
+    return res;
+  }
+}
+
+#endif // __se3_string_generator_hpp__