Merge pull request #80 from cmastalli/topic/q0-with-no-srdf

 Define q0 as neutral if the robot doesn't have a SRDF

python/example_robot_data/robots_loader.py

@@ -66,11 +66,11 @@ class RobotLoader(object):
 
         if self.srdf_filename:
             self.srdf_path = join(self.model_path, self.path, self.srdf_subpath, self.srdf_filename)
-            self.robot.q0 = readParamsFromSrdf(self.robot.model, self.srdf_path, self.verbose,
-                                               self.has_rotor_parameters, self.ref_posture)
+            self.robot.q0 = readParamsFromSrdf(self.robot.model, self.srdf_path, self.verbose, self.has_rotor_parameters,
+                                               self.ref_posture)
         else:
             self.srdf_path = None
-            self.robot.q0 = None
+            self.robot.q0 = pin.neutral(self.robot.model)
 
         if self.free_flyer:
             self.addFreeFlyerJointLimits()