diff --git a/python/example_robot_data/robots_loader.py b/python/example_robot_data/robots_loader.py
index da96f9af270dbb9ab2c0b2e786b2653a470bf336..0508d7f23cdeeaa9758757d6e8bcd54451dadad2 100644
--- a/python/example_robot_data/robots_loader.py
+++ b/python/example_robot_data/robots_loader.py
@@ -45,6 +45,7 @@ def addFreeFlyerJointLimits(robot):
 
 
 def loadANYmal(withArm=None):
+    REF_POSTURE = str()
     if withArm is None:
         URDF_FILENAME = "anymal.urdf"
         SRDF_FILENAME = "anymal.srdf"